JP2005299415A - Engine abnormal condition determination device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily, accurately discover various abnormality occurring in an engine at an early stage without providing a plurality of sensors and without specially disassembling the engine. <P>SOLUTION: An abnormal condition determination device 11 performs frequency analysis of forces in respective directions Fx, Fy, Fz from a force detection sensor 9 by a frequency analysis part 9 and selects a characteristic map according to engine rotation speed for each of the directions Fx, Fy, Fz by a characteristic map selection part 11b. A characteristic comparison determination part 11c compares frequency analysis value and the characteristic map in each of the directions Fx, Fy, Fz and determines whether abnormality exists in the engine 1. If abnormality is detected, an engine control device 13 issues an output reduction command and lights a warning lamp 12. A detection result analysis output part 11f stores the information together with time when abnormality has been detected in a failure diagnosis memory 14 with classifying cases based on any of the directions Fx, Fy, Fz in which abnormality has occurred. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an engine abnormal state determination device that detects various abnormalities that occur in an engine such as abnormal wear of piston rings and connecting rod cracks.

Generally, in a vehicle engine, various sensors are provided to detect the malfunction. For example, in Japanese Patent Laid-Open No. 7-151598, in order to detect engine knocking, a vibration sensor is attached to the cylinder head or cylinder block of the engine, and a predetermined specific resonance frequency component in the engine vibration is extracted. It is disclosed that whether or not knocking has occurred is determined by determining whether or not the frequency component is greater than a predetermined level.
JP 7-151598 A

  However, in the technique disclosed in Patent Document 1 described above, it is possible to determine whether knocking has occurred or not, but there is a problem that it is not possible to determine an abnormal state of another engine. For example, malfunctions such as abnormal piston ring wear, connecting rod cracks, and thrust metal wear are usually difficult to detect unless the engine is overhauled, causing phenomena such as reduced engine output and abnormal vibration. Discovered for the first time. It is desirable that such engine abnormality is detected as early as possible.

  The present invention has been made in view of the above circumstances, and various abnormalities occurring in the engine can be easily and accurately detected without providing a plurality of sensors, and in particular, without disassembling the engine. An object of the present invention is to provide an abnormal state determination device for an engine that can be used.

  The present invention acts in three axial directions, ie, the direction in which the piston reciprocates with respect to the engine, the direction of the rotation axis of the crankshaft, and the axial direction orthogonal to the plane determined by the piston reciprocation direction and the crankshaft rotation axis direction. Force detection means for detecting each force, reference characteristic storage means for preliminarily storing characteristics serving as a reference for signals of the forces acting in the three axial directions according to the operating state of the engine, and characteristics serving as the reference Comparison determination means for comparing the signals from the force detection means for each of the three axial directions to determine whether an abnormality has occurred in the engine, and the occurrence of the engine abnormality by the comparison determination means When determining the occurrence of the engine abnormality by the determination result analyzing means for classifying the abnormal state according to the direction in which the engine abnormality has occurred, and the comparison determining means It is characterized in that an engine output reducing means for reducing the engine output.

  The engine abnormal state determination device according to the present invention can easily and accurately detect various abnormalities occurring in the engine at an early stage without providing a plurality of sensors and in particular without disassembling the engine. Is possible.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a first embodiment of the present invention, FIG. 1 is a schematic explanatory diagram of an engine mounting system, FIG. 2 is a functional block diagram of an engine abnormal state determination device, and FIG. 3 is an engine abnormal state determination. FIG. 4 is a flowchart of the program, and FIG. 4 is an explanatory diagram of a comparison process between the reference frequency characteristic map and the frequency analysis value of the force detection sensor signal.

  In FIG. 1, reference numeral 1 denotes an automobile engine, and a torque converter portion housed in a torque converter case 2 and a front wheel final deceleration portion are connected to the rear of the engine 1, and a transmission is connected to the rear of the torque converter case 2. The automatic transmission part stored in case 3 is connected.

  Two locations on both sides of the lower portion of the engine 1 are supported on the vehicle body frame via a front cushion rubber 4, and a rear cover 5 at the rear end of the transmission case 3 is supported on the cross member 6 via a rear cushion rubber 7. ing. The upper portion of the torque converter case 2 is locked to the body side by a pitching stopper rod 8.

  The portions of the upper surface of the front cushion rubber 4 that come into contact with the engine 1 serve as force detection means for detecting the forces of Fx (width direction), Fy (front-rear direction), and Fz (up-down direction) in FIG. A force detection sensor 9 is embedded.

  Next, FIG. 2 shows functional blocks of the engine abnormal state determination device 11 according to the first embodiment. The engine abnormal state determination device 11 receives forces in the respective directions of Fx, Fy, and Fz from the force detection sensor 9 and receives an engine speed from the engine speed sensor 10. Then, based on these input signals, it is determined whether or not an abnormality has occurred in the engine 1. If an abnormality has occurred, the alarm lamp 12 provided in the combination meter is turned on, and the engine output is output to the engine control device 13. A signal to be lowered is output, and an abnormal state is stored in the failure diagnosis memory 14.

  That is, the engine abnormal state determination device 11 mainly includes a frequency analysis unit 11a, a characteristic map selection unit 11b, a characteristic comparison determination unit 11c, an alarm output unit 11d, an engine output command unit 11e, and a determination result analysis output unit 11f. ing.

  The frequency analysis unit 11a receives the forces in the respective directions of Fx, Fy, and Fz from the force detection sensor 9, and performs frequency analysis (spectrum analysis) of energy for each frequency as shown in FIG. 4B. The data is output to the characteristic comparison / determination unit 11c.

  The characteristic map selection unit 11b serves as a reference characteristic storage unit. The engine speed is input from the engine speed sensor 10, and the map at a corresponding engine speed is obtained from a map obtained and stored in advance through experiments or the like. Select a characteristic map. For example, as shown in FIG. 4A, the characteristic map selection unit 11b stores a plurality of frequency and energy characteristic maps corresponding to the engine speed for each direction of Fx, Fy, and Fz. . The characteristic map selected by the characteristic map selection unit 11b is output to the characteristic comparison determination unit 11c.

  The characteristic comparison / determination unit 11c receives frequency analysis values for each direction of Fx, Fy, and Fz from the frequency analysis unit 11a, and receives a frequency characteristic map for each direction of Fx, Fy, and Fz from the characteristic map selection unit 11b. Entered. Then, the frequency analysis value from the frequency analysis unit 11a and the frequency characteristic map are compared for each direction of Fx, Fy, and Fz (see FIG. 4C), and the frequency analysis value from the frequency analysis unit 11a is the frequency. If the set value differs from the characteristic map by more than the set value (the broken line area in FIG. 4C), it is determined that the engine 1 is abnormal.

  When the characteristic comparison / determination unit 11c determines that the engine 1 is abnormal, a signal is output to the alarm output unit 11d, the alarm lamp 12 provided in the combination meter is turned on, and the driver is checked. Prompt.

  In addition, when the abnormality of the engine 1 is determined by the characteristic comparison / determination unit 11c, a signal is output to the engine output command unit 11e serving as an engine output reduction unit, so that the engine 1 is not subjected to an excessive load. In order to reduce this, an output reduction command is issued to the engine control device 13.

  Further, when abnormality of the engine 1 is determined by the characteristic comparison determination unit 11c, a signal is output to the determination result analysis output unit 11f. Thus, the characteristic comparison determination unit 11c is provided as a comparison determination unit.

  When an abnormality of the engine 1 is determined, the determination result analysis output unit 11f receives a signal indicating that the engine abnormality has been detected from the characteristic comparison determination unit 11c. Then, the occurrence state of the abnormal state is stored in the failure diagnosis memory 14. For example, along with the time when the abnormality is detected, the direction in which Fx, Fy, or Fz has occurred is stored. Thus, by referring to the failure diagnosis memory 14 in the inspection, for example, in the case of a horizontally opposed engine, if an abnormality occurs in the Fx direction, the piston system of the engine 1 is abnormal (abnormal wear of the piston ring, It can be determined that a connecting rod crack or the like has occurred. Further, when an abnormality occurs in the Fy direction and the Fz direction, the crankshaft relationship (abrasion of thrust metal) of the engine 1 can be determined. In the case of a horizontally mounted engine, if an abnormality occurs in the Fy direction, it can be determined that an abnormality (abnormal wear of the piston ring, a connecting rod crack, etc.) has occurred in the piston system of the engine 1. Further, when an abnormality occurs in the Fx direction and the Fz direction, the crankshaft relationship (abrasion of thrust metal) of the engine 1 can be determined. As described above, the determination result analysis output unit 11f is provided as a determination result analysis unit.

  Next, the abnormal state determination program of the engine 1 will be described with reference to the flowchart of FIG. First, in step (hereinafter abbreviated as “S”) 101, necessary parameters are read, and the process proceeds to S102, where the frequency analysis unit 11a determines the force in each direction of Fx, Fy, Fz from the force detection sensor 9 as a frequency. Analyze (spectrum analysis).

  Next, in S103, the characteristic map selection unit 11b selects a characteristic map of frequency and energy corresponding to the engine speed for each direction of Fx, Fy, and Fz.

  In step S104, the characteristic comparison / determination unit 11c compares the frequency analysis value from the frequency analysis unit 11a with the frequency characteristic map for each direction of Fx, Fy, and Fz, and the engine 1 is abnormal. It is determined whether or not.

  Then, the process proceeds to S105, and if an abnormality is detected as a result of the comparison process in S104, the process proceeds to S106 and thereafter, and if no abnormality is detected, the program is directly exited.

  If an abnormality is detected in the engine 1 as a result of the determination in S105 and the process proceeds to S106, a signal is output to the engine output command unit 11e, and engine control is performed so as to reduce engine output so that an excessive load is not applied to the engine 1. An output reduction command is issued to the device 13.

  Next, in S107, a signal is output to the alarm output unit 11d, and the alarm lamp 12 provided in the combination meter is turned on to urge the driver to check the vehicle.

  Next, the process proceeds to S108, and the determination result analysis output unit 11f classifies the Fx, Fy, and Fz directions in which the abnormality occurred together with the time when the abnormality was detected, and the process proceeds to S109. Is stored in the failure diagnosis memory 14 and the program is exited.

  As described above, according to the first embodiment, since the abnormality of the engine 1 is detected from the force generated in the three axial directions of the engine 1 by the force detection sensor 9, the engine 1 is not disassembled. Comprehensive engine 1 abnormalities (such as abnormal piston ring wear, connecting rod cracks, thrust metal wear, etc.) can be detected. Further, when an abnormality occurs in the engine 1, it is possible to easily determine whether the abnormality is related to the piston or the crankshaft by the force in the direction in which the engine 1 is generated. Furthermore, since the sensor only needs to be provided with the force detection sensor 9, it is advantageous in terms of cost and space. In addition, when an abnormality occurs in the engine 1, the engine output is limited. Therefore, an excessive load is not applied to the engine 1, and the user can bring the vehicle to a service store and expect proper maintenance. it can.

  Next, FIGS. 5 to 7 show a second embodiment of the present invention, FIG. 5 is a functional block diagram of an engine abnormal state determination device, FIG. 6 is a flowchart of an engine abnormal state determination program, and FIG. It is explanatory drawing of the characteristic map of the threshold value of force. Unlike the first embodiment, the second embodiment is different from the first embodiment in that the reference characteristic compared with the signal from the force detection sensor is a force threshold value. Since it is the same, description is abbreviate | omitted.

  That is, in FIG. 5, reference numeral 20 denotes an engine abnormal state determination device. The engine abnormal state determination device 20 includes Fx, Fy, and Fz from the force detection sensor 9 as in the first embodiment. The direction force is input, and the engine speed is input from the engine speed sensor 10. Then, based on these input signals, it is determined whether or not an abnormality has occurred in the engine 1. If an abnormality has occurred, the alarm lamp 12 provided in the combination meter is turned on, and the engine output is output to the engine control device 13. A signal to be lowered is output, and an abnormal state is stored in the failure diagnosis memory 14.

  That is, the engine abnormal state determination device 20 mainly includes a force threshold setting unit 20a, a characteristic comparison determination unit 20b, an alarm output unit 20c, an engine output command unit 20d, and a determination result analysis output unit 20e.

  The force threshold value setting unit 20a serves as a reference characteristic storage unit. The engine speed is input from the engine speed sensor 10, and a characteristic map obtained and stored in advance through experiments or the like is used to determine the corresponding engine speed. Set the force threshold. For example, as shown in FIG. 7, a force threshold characteristic map corresponding to the engine speed is stored in the force threshold setting unit 20a for each direction of Fx, Fy, and Fz. Then, a force threshold corresponding to the engine speed is obtained for each direction of Fx, Fy, and Fz, and is output to the characteristic comparison / determination unit 20b.

  The characteristic comparison / determination unit 20b receives a force signal for each direction of Fx, Fy, and Fz from the force detection sensor 9, and the force threshold value for each direction of Fx, Fy, and Fz from the force threshold setting unit 20a. Entered. Then, the force signal from the force detection sensor 9 and the force threshold value from the force threshold setting unit 20a are compared for each direction of Fx, Fy, Fz, and the force signal from the force detection sensor 9 is the force threshold value. Is exceeded, it is determined that the engine 1 has an abnormality.

  When the characteristic comparison / determination unit 20b determines that the engine 1 is abnormal, a signal is output to the alarm output unit 20c, the alarm lamp 12 provided in the combination meter is turned on, and the driver is checked. Prompt.

  In addition, when the abnormality of the engine 1 is determined by the characteristic comparison / determination unit 20b, a signal is output to the engine output command unit 20d as the engine output reducing means, so that the engine 1 is not overloaded. In order to reduce this, an output reduction command is issued to the engine control device 13.

  Further, when the abnormality of the engine 1 is determined by the characteristic comparison determination unit 20b, a signal is output to the determination result analysis output unit 20e. Thus, the characteristic comparison determination unit 20b is provided as a comparison determination unit.

  When an abnormality of the engine 1 is determined, the determination result analysis output unit 20e receives a signal indicating that the engine abnormality is found from the characteristic comparison determination unit 20b. Then, the occurrence state of the abnormal state is stored in the failure diagnosis memory 14. For example, along with the time when the abnormality is detected, the direction in which Fx, Fy, or Fz has occurred is stored. Thus, by referring to the failure diagnosis memory 14 in the inspection, for example, in the case of a horizontally opposed engine, if an abnormality occurs in the Fx direction, the piston system of the engine 1 is abnormal (abnormal wear of the piston ring, It can be determined that a connecting rod crack or the like has occurred. Further, when an abnormality has occurred in the Fy direction and the Fz direction, the crankshaft relationship (abrasion of thrust metal) of the engine 1 can be determined. In the case of a horizontally mounted engine, if an abnormality occurs in the Fy direction, it can be determined that an abnormality (abnormal wear of the piston ring, a connecting rod crack, etc.) has occurred in the piston system of the engine 1. Further, when an abnormality occurs in the Fx direction and the Fz direction, the crankshaft relationship (abrasion of thrust metal) of the engine 1 can be determined. As described above, the determination result analysis output unit 11f is provided as a determination result analysis unit.

  Next, the abnormal state determination program of the engine 1 will be described with reference to the flowchart of FIG. First, in S201, necessary parameters are read, and the process proceeds to S202. A force threshold setting unit 20a sets a force threshold corresponding to the engine speed for each direction of Fx, Fy, and Fz.

  Next, in S203, the characteristic comparison / determination unit 20b compares the signal from the force detection sensor 9 with the force threshold value for each direction of Fx, Fy, and Fz to determine whether or not there is an abnormality in the engine 1. judge.

  Then, the process proceeds to S204, and if an abnormality is detected as a result of the comparison process in S203, the process proceeds to S205 and thereafter, and if no abnormality is detected, the program is directly exited.

  If an abnormality is detected in the engine 1 as a result of the determination in S204 and the process proceeds to S205, a signal is output to the engine output command unit 20d, and engine control is performed so as to reduce the engine output so that the engine 1 is not overloaded. An output reduction command is issued to the device 13.

  Next, in S206, a signal is output to the alarm output unit 20c, and the alarm lamp 12 provided in the combination meter is turned on to urge the driver to check the vehicle.

  Next, the process proceeds to S207, and the determination result analysis output unit 20e classifies in which direction Fx, Fy, and Fz the abnormality has occurred, along with the time when the abnormality was detected, and proceeds to S208 to store these information. Is stored in the failure diagnosis memory 14 and the program is exited.

  As described above, according to the second embodiment, in addition to the effect described in the first embodiment, the signal from the force detection sensor 9 can be realized without performing frequency analysis processing, so that the control can be further simplified. it can.

  In this embodiment, the reference characteristic is selected according to the engine speed, but in addition to this, more precise control is performed by adding parameters of the engine operating state such as the throttle opening. It can also be realized.

Schematic explanatory diagram of an engine mounting system according to the first embodiment of the present invention. Same as above, functional block diagram of engine abnormal state determination device Same as above, flowchart of engine abnormal state determination program Same as above, explanatory diagram of comparison processing between reference frequency characteristic map and frequency analysis value of force detection sensor signal Functional block diagram of the engine abnormal state determination device according to the second embodiment of the present invention. Same as above, flowchart of engine abnormal state determination program Same as above, explanatory diagram of characteristic map of threshold value of standard force

Explanation of symbols

1 Engine 4 Front cushion rubber 9 Force detection sensor (force detection means)
DESCRIPTION OF SYMBOLS 10 Engine speed sensor 11 Abnormal state determination apparatus 11a Frequency analysis part 11b Characteristic map selection part (reference | standard characteristic storage means)
11c Characteristic comparison determination unit (comparison determination means)
11d Alarm output unit 11e Engine output command unit (engine output reduction means)
11f Determination result analysis output unit (determination result analysis means)
DESCRIPTION OF SYMBOLS 12 Alarm lamp 13 Engine control apparatus 14 Failure diagnosis memory 20 Abnormal state determination apparatus 20a Force threshold setting part (reference characteristic storage means)
20b Characteristic comparison determination unit (comparison determination means)
20c alarm output unit 20d engine output command unit (engine output reduction means)
20e judgment result analysis output unit (judgment result analysis means)
Agent Patent Attorney Susumu Ito

Claims (3)

Detects the forces acting in the three axial directions, the direction of the piston reciprocating with respect to the engine, the direction of the rotational axis of the crankshaft, and the axial direction orthogonal to the plane determined by the direction of reciprocating piston movement and the direction of the crankshaft rotational axis. Force detecting means for
Reference characteristic storage means for storing in advance characteristics that serve as a reference for the signal of the force acting in each of the three axial directions according to the operating state of the engine;
A comparison determination means for comparing the reference characteristic and the signal from the force detection means for each of the three axial directions to determine whether an abnormality has occurred in the engine;
A determination result analyzing means for classifying an abnormal state according to a direction in which the engine abnormality has occurred when the comparison determination means determines the occurrence of the engine abnormality;
Engine output reduction means for reducing engine output when the comparison determination means determines occurrence of the engine abnormality;
An engine abnormal state determination device characterized by comprising:   The reference characteristic stored in advance by the reference characteristic storage means is a frequency characteristic, and the comparison / determination means compares the reference frequency characteristic with a signal obtained by frequency analysis of the signal from the force detection means. 2. The engine abnormal state determination device according to claim 1, wherein it is determined whether or not an abnormality has occurred in the engine.   The reference characteristic stored in advance in the reference characteristic storage means is a force value threshold value, and the comparison / determination means compares the reference force threshold value with a signal from the force detection means to compare the engine with the threshold value. 2. The engine abnormal state determination device according to claim 1, wherein it is determined whether or not an abnormality has occurred.

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