JP2008082742A - Fragment detection sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the fragment of the material mixed in the liquid, the material of which is an any of performance of ceramic, non-metallic, non-magnetic and non-conductive materials etc. <P>SOLUTION: The fragment detection sensor which is a detector for detecting the fragment mixed in the liquid includes: two flat plates 5 and 7 opposite to each other; the flat plate moving mechanism 9 for nipping the fragment between the two flat plates 5 and 7 by moving the flat plates at least one flat plate 7 between the two flat plates 5 and 7; the measurement/determination means 14 which is a means for detecting the existing, magnitude or accumulation of the fragment detecting means by measuring the gaps between the two flat plates 5 and 7; and the displacement sensor for measuring the gap between the above two flat plates 5 and 7 as a measuring means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a debris detection sensor that detects debris mixed in a liquid such as lubricating oil.

Conventionally, a metal check sensor or an oil check has been used as a device for detecting that metal fragments or metal particles generated by wear or damage of engines, transmissions, bearings, etc. are mixed in lubricating oil for automobiles, aircraft, helicopters, etc. Metal piece detection devices called sensors or debris sensors have been proposed (Patent Documents 1 to 5).
Such metal piece detection devices are used as means for inspecting the soundness of various devices such as engines, gearboxes, bearings, etc., and information on deterioration in each part of the device to be inspected is a destructive failure in these parts. Can be obtained before it occurs.
Japanese Unexamined Patent Publication No. 55-052943 JP-A-61-253455 JP 2000-32248 A Japanese Patent No. 2703502 Japanese Patent No. 2865857

At present, there is a demand for miniaturization and high speed particularly in aircraft jet engines. Conventionally, in bearings for main shafts of aircraft jet engines, metal materials have been used for the rolling elements. However, it is difficult to achieve higher speeds with the current rolling element materials. In order to withstand high speed, the rolling elements of the bearing need to be ceramic balls or rollers made of silicon nitride (Si3N4) or the like. In addition, when ceramic balls or ceramic rollers are applied to the jet engine bearing, the performance is greatly improved, and consequently the efficiency of the jet engine is improved, which may reduce the environmental load.
On the other hand, conventional metal piece detection devices can detect only metal, magnetic or conductive material fragments, and cannot detect ceramic materials characterized by non-metal, non-magnetic and non-conductivity. It was. Therefore, for example, in the case of a bearing using a ceramic rolling element, it is impossible to obtain information on deterioration or damage of the rolling element using the metal piece detection device before a destructive failure occurs. Therefore, at present, the bearing having such a configuration is used only for aircraft having limited applications.

  An object of the present invention is to detect a fragment mixed in a liquid regardless of whether the material of the fragment is a metal / non-metal, magnetic / non-magnetic, conductive / non-conductive material property, etc. It is to provide a detection sensor.

The debris detection sensor of the present invention is a sensor that detects debris mixed in a liquid, and moves two opposing flat plates and at least one of the two flat plates between the two flat plates. A flat plate moving mechanism for sandwiching the debris, and a measurement / determination means for detecting the presence, size, or accumulation amount of the debris by measuring a gap between the two flat plates, and between the two flat plates A displacement sensor is used as means for measuring the gap. According to this configuration, one of the two flat plates is operated, the gap between the two flat plates is measured, and the presence / absence or size or accumulation amount of debris is determined from the measured value. The state of debris (the presence or absence of debris and the size of the debris) mixed in the lubricant or other liquid to be inspected, and the material of the debris is metal / nonmetal, magnetic / nonmagnetic, conductive / nonconductive, etc. It can be estimated regardless of which material characteristic.
In addition, when the above debris detection sensor is incorporated in an automobile, aircraft, helicopter, etc., it is possible to monitor the state of debris mixed in the lubricating oil. Can inform you that a replacement is necessary. In addition, the detected information can be obtained before a destructive failure occurs due to deterioration or damage.

  In the present invention, the displacement sensor may use at least one of a magnetic type, an eddy current type, and an optical type. If it is a magnetic type, eddy current type, or optical type displacement sensor, it can detect with a simple structure with high precision.

  In the present invention, a linear motion actuator may be used as the flat plate moving mechanism. When a linear actuator is used, unlike the case where a rotational drive source is used, a mechanism for converting rotation into linear motion is not required, and the fragment detection sensor can be configured simply and compactly.

  In the present invention, the linear actuator may be an electromagnetic type, a hydraulic type or a pneumatic type.

  The debris detection sensor of the present invention is a sensor that detects debris mixed in a liquid, and moves two opposing flat plates and at least one of the two flat plates between the two flat plates. A flat plate moving mechanism for sandwiching the debris, and a measurement / determination means for detecting the presence, size, or accumulation amount of the debris by measuring a gap between the two flat plates, and between the two flat plates Since the displacement sensor is used as a means to measure the gap, whether the material of the debris mixed in the liquid is metal, nonmetal, magnetic / nonmagnetic, conductive / nonconductive, etc. The detected information can be obtained before a destructive failure occurs due to deterioration or damage.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic configuration diagram of a fragment detection sensor of this embodiment. The broken piece detection sensor is a sensor for detecting broken pieces made of various materials mixed in a liquid to be inspected, and is composed of two flat plates 5 and 7 facing each other and at least one of the two flat plates 5 and 7. By measuring the distance between the two flat plates 5 and 7, the flat plate moving mechanism 9 for moving the single flat plate in a facing direction and sandwiching the debris 13 (FIG. 3) between the two flat plates 5 and 7, the broken pieces are measured. And measurement / determination means 14 for detecting the presence / absence, size, or accumulation amount of 13. In the case of this debris detection sensor, the lubricating oil is the liquid to be inspected.

  The two flat plates 5 and 7 and the flat plate moving mechanism 9 are incorporated in the sensor unit 1. This sensor unit 1 has a base member 4 provided with an oil passage 4a through which lubricating oil to be inspected flows, and an oil supply pipe 2 is connected to one end of the oil passage 4a. An oil drain pipe 3 is connected to the end. In this case, the lubricating oil flows from the oil path 2 a of the oil supply pipe 2 through the oil path 4 a of the base member 4 to the oil path 3 a of the oil discharge pipe 3. For example, the oil supply pipe 2 is connected to a pipe for collecting lubricating oil used in an engine, a gear box, a bearing, and the like, and the oil drain pipe 3 is connected to a pipe to an oil tank.

  One flat plate 5 of the two flat plates 5 and 7 is a fixed flat plate made of a conductive material. The base member 4 is interposed in the middle of the oil passage 4a of the base member 4 via a flat plate fixing member 6 made of an insulating material. It is fixed in an electrically insulated state. The fixed flat plate 5 is arranged so that the surface thereof faces the oil passage 4a.

  The flat plate moving mechanism 9 is a linear motion actuator composed of a push-pull solenoid or the like, and an actuator fixing member 10 so that the movable shaft 9a can advance and retract in a direction perpendicular to the penetrating direction of the oil passage 4a of the base member 4. It is being fixed to the base member 4 via. A state in which the other flat plate 7 of the two flat plates 5 and 7 is electrically insulated from the tip of the movable shaft 9a of the linear actuator 9 via a flat plate fixing member 8 made of an insulating material. It is fixed with. The flat plate 7 is a movable flat plate that can be moved forward and backward integrally with the movable shaft 9a of the linear actuator 9. The flat plate 7 is made of a conductive material in the same manner as the fixed flat plate 5, and penetrates the base member 4 to enter the oil passage 4a. Facing the fixed flat plate 5. Here, an example in which a push-pull solenoid is used as the linear actuator 9 is shown, but any type of linear actuator can be used. For example, a combination of an electric motor and a ball screw may be used, or an air pressure or hydraulic pressure may be used. When the linear actuator 9 is operated, the movable flat plate 7 installed on the movable shaft 9 a via the flat plate fixing member 8 advances and retreats, and approaches or moves away from the fixed flat plate 5.

The movable shaft 9a of the linear actuator 9 is urged in the advancing direction by a compression spring 12 interposed between a spring receiving member 11 fixed to the rear end portion and the actuator fixing member 10.
FIG. 1 shows a state in which power is supplied to the linear actuator 9. At this time, the movable shaft 9 a is retracted by compressing the compression spring 12, and the movable flat plate 7 is located away from the fixed flat plate 5. On the other hand, in a state where the power is not applied to the linear actuator 9, as shown in FIG. 2, the force is restored by the compression spring 12 that is compressed when the power is turned on, and the movable plate 7 moves to a position where it contacts the fixed plate 5. To do. Since the movable plate 7 and the fixed plate 5 are in contact with each other, the movable plate 7 is preloaded by the compression spring 12, so that the movable plate 7 and the fixed plate 5 are in contact with each other at a constant pressure.

  The measurement / determination unit 14 includes a displacement sensor 16 and a determination unit 15. The displacement sensor 16 is a means for measuring a gap between the movable flat plate 7 and the fixed flat plate 5, and is provided in a state of being embedded in the fixed flat plate 5, for example. Here, for example, an eddy current type is used as the displacement sensor 16, but other types such as a magnetic type and an optical type may be used. For example, when an optical sensor is used as the displacement sensor 16, the fixed plate 5 and the movable plate 7 may not be made of a conductive material, and the base member 4 or the movable member may be moved without interposing the plate fixing members 6 and 8. You may fix to the axis | shaft 9a. The determination means 15 is a means for determining the state of the debris 13 (FIG. 3) in the lubricating oil from the measurement value of the displacement sensor 16, for example, determination of a table or an arithmetic expression that defines the relationship between the measurement value and the determination result. It has a rule, and the determination rule is compared with the measured value, and a determination result is output for the presence / absence, size, accumulated amount, etc. of the fragments.

Next, the operation for detecting the fragments from the lubricating oil mixed with the fragments made of various materials caused by wear or damage of the engine, gear box, bearing or the like using this fragment detection sensor will be described. .
As described above, when the linear actuator 9 is powered on, the movable shaft 9a moves backward as shown in FIG. 1, and the movable flat plate 7 installed on the movable shaft 9a via the flat plate fixing member 8 is fixed to the fixed flat plate 5. Get away from. At this time, the compression spring 12 installed between the spring receiving member 11 fixed to the movable shaft 9a and the actuator fixing member 10 is compressed.

Next, as the liquid to be inspected, the lubricating oil used in the engine, gearbox, bearing, etc. is passed through the oil passage 2a of the oil supply piping 2 and the oil passage 4a of the base member 4 to the oil in the oil discharge piping 3. In this state, when the application of power to the linear actuator 9 is stopped, the movable flat plate 7 approaches the fixed flat plate 5 integrally with the movable shaft 9a by the restoring force of the compression spring 12. Advance.
At this time, as shown in FIG. 3, if the debris 13 generated due to wear or breakage of the engine, gear box, bearing, or the like is mixed in the lubricating oil flowing through the oil passage 4 a of the base member 4, the debris 13 Is sandwiched between the movable flat plate 7 and the fixed flat plate 5. Thereby, a gap d is generated between the movable flat plate 7 and the fixed flat plate 5 by the thickness of the debris 13. The displacement sensor 16 measures the gap d, and the determination means 15 estimates the size of the fragments 13 or the accumulated amount from the measured value.

  On the other hand, when there is no debris 13 between the two flat plates 5 and 7, a gap d is formed by a very small film of lubricating oil, or the flat plates 5 and 7 are in contact with each other. In the case of the extremely small gap d due to the lubricating oil, the measured value of the gap by the displacement sensor 16 is considerably smaller than that when the debris 13 is sandwiched. Further, when the flat plates 5 and 7 are in contact with each other, the measured value of the displacement sensor 16 is almost zero. Therefore, from this measurement result, the determination means 15 can determine the presence or absence of the fragments 13.

As described above, in the fragment detection sensor of this embodiment, the movable flat plate 7 is operated, the gap between the movable flat plate 7 and the fixed flat plate 5 is measured by the displacement sensor 16, and the measured value of the displacement sensor 16 is used to measure the fragment 13. Since the presence / absence, size, or accumulated amount is determined by the determination means 15, the state of the fragment 13 mixed in the lubricating oil is determined based on whether the material of the fragment 13 is metal / nonmetal, magnetic / nonmagnetic, conductive / nonconductive. It can be estimated regardless of which material property it is.
In addition, when the above debris detection sensor is incorporated in an automobile, aircraft, helicopter, etc., it is possible to monitor the state of debris mixed in the lubricating oil. It is possible to inform that replacement is necessary, and safety is improved. In addition, since the life and aging of machine parts can be predicted, there is no need for unnecessary or delayed replacement of parts, thereby improving economy.

  FIG. 4 shows another embodiment of the debris detection sensor of the present invention. In this embodiment, the displacement sensor 16 in the embodiment shown in FIG. 1 is provided at a position facing the rear end of the movable shaft 9 a in the actuator fixing member 10.

  In the case of this embodiment, the displacement sensor 16 measures the amount of displacement of the movable shaft 9a. However, since the movable flat plate 7 is fixed to the movable shaft 9a via the flat plate fixing member 8, the displacement of the movable shaft 9a. The gap d between the fixed flat plate 5 and the movable flat plate 7 can be detected from the amount of displacement.

  FIG. 5 shows still another embodiment of the fragment detection sensor of the present invention. In this embodiment, in the embodiment shown in FIG. 1, a recording means 50 is added to the next stage of the judging means 15 so that the state of the debris 13 mixed in the lubricating oil can be monitored in real time. Note that the determination unit 15 may determine that a failure has occurred due to the gap fluctuation value measured by the displacement sensor 16 exceeding a predetermined threshold.

It is a schematic block diagram at the time of power activation of the fragment detection sensor which concerns on 1st Embodiment of this invention. It is a schematic block diagram at the time of the power supply stop of the same fragment detection sensor. It is explanatory drawing of the detection operation of the same fragment detection sensor. It is explanatory drawing of the detection operation | movement of the fragment detection sensor which concerns on other embodiment of this invention. It is explanatory drawing of the detection operation | movement of the fragment detection sensor which concerns on further another embodiment of this invention.

Explanation of symbols

5 ... Fixed flat plate 7 ... Movable flat plate 9 ... Linear motion actuator (flat plate moving mechanism)
13: Fragment 14: Measurement / judgment means 16: Displacement sensor

Claims (4)

  A sensor for detecting debris mixed in the liquid, two opposing flat plates, and a flat plate moving mechanism for moving at least one of the two flat plates to sandwich the debris between the two flat plates Measuring / determining means for detecting the presence / absence, size, or accumulated amount of the debris by measuring a gap between the two flat plates, and a displacement sensor in the means for measuring the gap between the two flat plates A debris detection sensor characterized by using the above.   2. The fragment detection sensor according to claim 1, wherein the displacement sensor uses at least one of a magnetic type, an eddy current type, and an optical type.   3. A fragment detection sensor according to claim 1, wherein a linear motion actuator is used as the flat plate moving mechanism.   4. The debris detection sensor according to claim 3, wherein the linear motion actuator is of an electromagnetic type, a hydraulic type or a pneumatic type.

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