JP2008070302A - Vibration transmission characteristics analyzer for engine block, and vibration transmission characteristics analysis method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To analyze the vibration transmission characteristic, in response to the operating state of an actual engine. <P>SOLUTION: This vibration transmission characteristics analyzer for an engine block comprises an exciting device 130, that is connected to a knock sensor mounting hub 163 disposed in a cylinder block 161 and excites the engine block 160 only for a period (t), defined as the duration of vibration when knocking actually occurs; a cylinder block vibration detecting sensor, arranged on the inner surface of a cylinder bore of the cylinder block 161; and a cylinder head vibration detecting sensor, arranged in a plug hole disposed in a cylinder head 162. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vibration transfer characteristic analyzing apparatus and a vibration transfer characteristic analyzing method, and more particularly to a vibration transfer characteristic analyzing apparatus for an engine block in an engine and a vibration transfer characteristic analyzing method using the vibration transfer characteristic analyzing apparatus.

  One of the engine controls for obtaining a comfortable ride when a vehicle equipped with an engine that is an internal combustion engine is running is a method for detecting the occurrence of knocking in the engine and controlling the engine so as to eliminate knocking. There is. In order to realize this control, a knocking sensor is provided in the engine, vibration generated when knocking occurs is detected by the knocking sensor, and combustion conditions of the engine are set based on this detection information.

  When knocking occurs, it is necessary to accurately detect knocking vibration generated in the engine block by a knocking sensor. Specifically, it is important to know in advance the transmission characteristics of knocking vibration generated in the engine block when knocking occurs (hereinafter referred to as knocking vibration transmission characteristics). Therefore, it is conceivable to experimentally give a vibration to the engine block to generate a knocking vibration in a pseudo manner in the engine block and to grasp the knocking vibration transmission characteristic in advance.

  Japanese Patent Laying-Open No. 2005-3000524 (Patent Document 1) discloses a vibration transfer characteristic analysis device for an engine block for measuring and analyzing knocking vibration in advance. The vibration transmission characteristic analysis device described in Patent Document 1 is used to analyze vibration transmission of an engine block by exciting an engine block including a cylinder head and a cylinder block having a cylinder bore. It is a characteristic analysis device. The vibration transfer characteristic analyzer includes a cylinder block vibration measuring device disposed in a region corresponding to the combustion chamber on the inner surface of the cylinder bore, a cylinder head vibration measuring device disposed on the inner surface of the cylinder head facing the combustion chamber, And a vibration exciter connected to a predetermined position of the engine block for applying a predetermined vibration to the engine block.

According to the engine block vibration transfer characteristic analyzer described in this publication, a predetermined vibration is applied to the engine block by the vibration exciter, and the transmission of this vibration can be measured by the cylinder block vibration measuring instrument and the cylinder head vibration measuring instrument. It is said. Since the piston position when knocking occurs in the engine is in the range of about 10 ° to 60 ° after compression top dead center (ATDC), vibration transmitted to the cylinder block in the combustion chamber is caused by the piston. The vibration transmission from the cylinder head (head lateral vibration) becomes dominant. On the other hand, when the piston position is lowered, the suppression of the cylinder block by the piston is released, and the cylinder block starts to resonate. This cylinder block resonance affects engine noise at the ignition timing of knocking, and affects the SN (knocking signal / noise signal) ratio in the knocking sensor. Therefore, by installing two types of vibration measuring devices, the cylinder block vibration measuring device and the cylinder head vibration measuring device, the response signal when a predetermined vibration is applied to the engine block by the vibration exciter is measured. By picking up with a measuring device and a cylinder head vibration measuring device, it is possible to grasp the vibration characteristics of the cylinder block and the vibration characteristics of the cylinder head. As a result, it is possible to obtain an S / N ratio based on a knocking signal (S: vibration characteristic of the cylinder head) and a noise signal (N: vibration characteristic of the engine block) as vibration transmission characteristics of the engine block.
JP-A-2005-300524

  However, in Japanese Patent Application Laid-Open No. 2005-3000524, there is no description regarding preferable vibration to be given to the engine block. Therefore, there is room for further improvement in order to perform analysis in accordance with actual driving conditions.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an engine block vibration transfer characteristic analysis apparatus and vibration transfer characteristic analysis method capable of improving the analysis accuracy of vibration transfer characteristics. Is to provide.

  An engine block vibration transmission characteristic analyzer according to a first aspect of the present invention is an engine used to analyze vibration transmission of an engine block by exciting an engine block including a cylinder head and a cylinder block having a cylinder bore. This is an apparatus for analyzing vibration transmission characteristics of a block. This vibration transmission analyzing device is connected to the engine block and is provided on the inner surface of the cylinder bore for measuring vibrations. The vibration device is configured to vibrate the engine block for a predetermined time as the time when vibration due to knocking occurs. A block vibration measuring device and a cylinder head vibration measuring device arranged on the inner surface of the cylinder head and measuring vibration are included.

  According to the first invention, the vibration is applied to the engine block by the vibration exciter for a time that is predetermined as the time during which the vibration due to knocking occurs. The transmission of this vibration is measured by a cylinder block vibration measuring device and a cylinder head vibration measuring device. Thereby, it is possible to obtain a vibration simulating a state in which knocking has occurred in the engine. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, it is possible to provide an engine block vibration transfer characteristic analyzing apparatus capable of improving the vibration transfer characteristic analysis accuracy.

  In the vibration transmission characteristic analyzing apparatus for an engine block according to the second invention, in addition to the configuration of the first invention, the vibration exciter is predetermined with a predetermined attenuation rate as an attenuation rate of vibration due to knocking. Gives vibration to the engine block for time.

  According to the second aspect of the invention, vibration is applied to the engine block for a predetermined time with a predetermined attenuation rate as the attenuation rate of vibration due to knocking. The transmission of this vibration is measured by a cylinder block vibration measuring device and a cylinder head vibration measuring device. Thereby, it is possible to obtain vibration in a state closer to a state where knocking has occurred in the engine. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  In the vibration transmission characteristic analyzing apparatus for an engine block according to the third invention, in addition to the configuration of the first or second invention, the cylinder block vibration measuring device generates vibration in the cylinder block by a piston arranged in the cylinder bore. It is arranged at a position corresponding to the position of the piston at the time.

  According to the third invention, the cylinder block vibration measuring instrument is disposed at a position corresponding to the position of the piston when vibration is generated in the cylinder block by the piston disposed in the cylinder bore. Vibration is measured by this cylinder block vibration measuring instrument. As a result, it is possible to analyze a vibration transmission characteristic that takes into account the influence of vibration generated by the piston when the engine is actually operated, such as vibration due to piston slap. Therefore, it is possible to analyze the vibration transfer characteristics more in line with actual driving conditions. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  An engine block vibration transmission characteristic analysis method according to a fourth aspect of the present invention is an engine block vibration transmission characteristic analysis method including a cylinder head and a cylinder block having a cylinder bore. The vibration transfer characteristic analysis method includes a step of applying vibration to the engine block for a predetermined time as a time when vibration due to knocking occurs, a step of measuring vibration of the inner surface of the cylinder bore, and a step of measuring vibration of the cylinder head And analyzing vibration transmission of the cylinder block based on vibration of the inner surface of the cylinder bore and vibration of the cylinder head.

  According to the fourth aspect of the invention, the engine block is vibrated for a predetermined time as the time when the vibration due to knocking occurs. Vibrations of the cylinder bore inner surface and cylinder head vibration are measured. Thereby, it is possible to obtain a vibration simulating a state in which knocking has occurred in the engine. Based on these vibrations, vibration transmission of the cylinder block is analyzed. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, it is possible to provide an engine block vibration transfer characteristic analyzing apparatus capable of improving the vibration transfer characteristic analysis accuracy.

  In the vibration transmission characteristic analysis method for an engine block according to the fifth invention, in addition to the configuration of the fourth invention, the step of applying vibration to the engine block has a predetermined damping rate as a damping rate of vibration due to knocking, Applying vibration to the engine block for a predetermined time.

  According to the fifth aspect, vibration is applied to the engine block for a predetermined time at a predetermined attenuation rate as the attenuation rate of vibration due to knocking. The transmission of this vibration is measured. Thereby, it is possible to obtain vibration in a state closer to a state where knocking has occurred in the engine. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  In the vibration transmission characteristic analysis method for an engine block according to the sixth invention, in addition to the configuration of the fourth or fifth invention, the step of measuring the vibration of the inner surface of the cylinder bore is performed by the piston arranged in the cylinder bore. And a step of measuring vibration by a cylinder block vibration measuring device disposed on the inner surface of the cylinder bore at a position corresponding to the position of the piston when vibration is generated.

  According to the sixth invention, the vibration is measured by the cylinder block vibration measuring device disposed at a position corresponding to the position of the piston when vibration is generated in the cylinder block by the piston disposed in the cylinder bore. As a result, it is possible to analyze a vibration transmission characteristic that takes into account the influence of vibration generated by the piston when the engine is actually operated, such as vibration due to piston slap. Therefore, it is possible to analyze the vibration transfer characteristics more in line with actual driving conditions. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  FIG. 1 is an overall perspective view showing a configuration of an engine block vibration transfer characteristic analyzing apparatus 100 and a computer 200 according to the present embodiment, and FIG. 2 is a side view showing a structure of the engine block vibration transfer characteristic analyzing apparatus 100. FIG. 3 is a schematic view showing the structure of the high-precision height adjusting mechanism 120, and FIG. 4 is a schematic cross-sectional view showing the internal configuration of the engine block. 5 is an enlarged cross-sectional view of the cylinder head 162, and FIG. 6 is a view taken along line VI in FIG.

  As shown in FIGS. 1 and 2, the structure of the vibration transfer characteristic analyzing apparatus 100 in the present embodiment has an engine block 160 on which a vibration transfer characteristic is to be analyzed on a surface plate 110, and a predetermined value for the engine block 160. And a vibration exciter 130 for applying the above vibration. The vibration applied to the engine by the vibration exciter 130 will be described later.

  Engine block 160 in the present embodiment is an engine block of a multi-cylinder engine having a plurality of cylinders. An anti-vibration rubber 150 is interposed between the engine block 160 and the surface plate 110 in order to block vibration from the outside. In addition, the high-accuracy height adjustment mechanism 120 is interposed between the vibration device 130 and the surface plate 110 from the viewpoint of accurately applying vibration to the engine block 160. As the vibration device 130, an electromagnetic vibration device or the like is used. Note that the external dimensions of the vibration transfer characteristic analyzing apparatus 100 in the present embodiment are about 450 mm wide, 450 mm deep, and 400 mm high.

  As shown in FIG. 2, the vibration device 130 has a support bolt 131 of the vibration device 130 in a U-shaped groove 123 provided in a holding jig 122 attached to the base 121 of the high-precision height adjustment mechanism 120. It is held and allows for a rough height adjustment. Further, as shown in FIG. 3, the high-precision height adjusting mechanism 120 includes a wedge member 121b and a wedge member 121c disposed in the case 121a of the base 121, and by rotating the handle 121d, The wedge member 121c moves in the X direction and the Y direction, and the height position can be adjusted in units of several tens of micrometers.

  As shown in FIG. 2, the engine block 160 includes a cylinder block 161 having a cylinder bore and a cylinder head 162, and the vibration shaft 140 of the vibration device 130 is attached to a knock sensor mounting boss 163 provided on the cylinder block 161. It is connected. The knock sensor mounting boss 163 is a cylindrical protrusion for mounting a knock sensor that detects the occurrence of knocking in an actual engine.

  Referring to FIG. 4, a cylinder block vibration detection sensor 310 as a cylinder block vibration measuring device is disposed on the inner surface of cylinder bore 161A. A cylinder block vibration detection sensor 310 is provided for each cylinder.

  In an actual engine, a piston 164 that slides up and down is disposed in the cylinder bore 161A. The cylinder block vibration detection sensor 310 is provided at a position corresponding to the position of the piston 164 when vibration is generated in the cylinder block 161 by the piston slap in a state where the actual engine is operated.

  For example, when a piston slap is generated within a crank angle range of 40 ° ATDC to 70 ° ATDC, the cylinder block vibration detection sensor 310 is provided at a position corresponding to the piston position at 40 ° ATDC to 70 ° ATDC. That is, the cylinder block vibration detection sensor 310 is provided at a position corresponding to a vibration generation point due to piston slap.

  By using the vibration obtained by the cylinder block vibration detection sensor 310 provided at such a position, the vibration transmission characteristics at the time of occurrence of knocking of the engine block 160 are analyzed as described later, so that noise other than vibration due to knocking is analyzed. Analysis can be performed with the influence of. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  Referring to FIG. 5, a cylinder head vibration detection sensor 320 as a cylinder head vibration measuring device is disposed in a plug hole 162p provided in the cylinder head 162. The cylinder head vibration detection sensor 320 includes special bolts 301, It consists of a metal cube 302 and a sensor 303. A more specific configuration will be described later. As shown in FIG. 6, the plug hole 162p is provided in a central region of the cylinder head 162 surrounded by an intake valve hole 162i and an exhaust valve hole 162e provided in the cylinder head 162. Further, since the plug hole 162p is formed with high precision by machining, the cylinder head vibration detection sensor 320 can be attached to the cylinder head 162 with high precision. A cylinder head vibration detection sensor 320 is provided for each cylinder.

  A vibration analysis method of the engine block 160 when knocking occurs, using the vibration transfer characteristic analysis apparatus 100 having the above-described configuration, specifically, a knocking signal (S: vibration characteristic of the cylinder head) is used as the vibration transfer characteristic of the engine block 160. ) And a noise signal (N: vibration characteristic of the engine block), a method for obtaining the SN ratio will be described. First, a predetermined vibration is applied to the engine block 160 from the vibration shaft 140 connected to the knock sensor mounting boss 163 of the engine block 160 using the vibration device 130.

  Next, the vibration signal 1 generated in the cylinder block 161 and the vibration signal 2 generated in the cylinder head 162 are picked up using the cylinder block vibration detection sensor 310 and the cylinder head vibration detection sensor 320. The vibration signal 1 and the vibration signal 2 are input to the computer 200, and vibration transmission characteristics (S / N ratio) when the engine block 160 is knocked are analyzed. The vibration transfer characteristic is analyzed for each cylinder.

  Here, a specific analysis method of vibration transfer characteristics using the cylinder block vibration detection sensor 310 and the cylinder head vibration detection sensor 320 will be described with reference to FIGS. 7 is a schematic diagram illustrating the vibration generated in the cylinder block 161 and the vibration generated in the cylinder head 162, and FIG. 8 is a diagram illustrating the relationship between the signal intensity at the knocking ignition timing and the knocking occurrence frequency. .

  As shown in FIG. 7, the position of the piston 164 at the time of occurrence of knocking in the actual engine is within a range of about 10 ° to 60 ° after compression top dead center (ATDC), so that it is transmitted to the cylinder block 161 in the combustion chamber A. The vibration to be suppressed is suppressed by the piston 164, and vibration transmission from the cylinder head 162 (S: head portion vibration response) becomes dominant. On the other hand, when the position of the piston 164 is lowered, the suppression of the cylinder block 161 by the piston 164 is released, and the cylinder block 161 starts to resonate (N: liner portion vibration response).

  The resonance of the cylinder block 161 affects engine noise at the ignition timing of knocking and increases the noise signal. As a result, the SN (knocking signal / noise signal: head portion vibration response S / liner portion vibration response N) in the knocking sensor is increased. ) Will adversely affect the ratio. That is, as shown in FIG. 8, the noise signal N is shifted to the noise signal N ′ (intensity is increased), and as a result the noise signal approaches the knocking determination level (S), the SN ratio is deteriorated. Become. In this manner, the lateral vibration (initial vibration) of the engine block 160 at the ignition timing of occurrence of knocking is dominated by vibration transmission from the cylinder head 162, and the signal from the cylinder block 161 becomes a noise signal.

  In view of this, in the vibration transfer characteristic analyzing apparatus 100 according to the present embodiment, two types of vibration detection sensors, the cylinder block vibration detection sensor 310 and the cylinder head vibration detection sensor 320, are disposed in the combustion chamber A. A response signal when a predetermined vibration is applied to the engine block 160 by the vibration device 130 is picked up by the cylinder block vibration detection sensor 310 and the cylinder head vibration detection sensor 320, whereby the vibration characteristics of the cylinder block 161 and the vibration of the cylinder head 162 are picked up. It is possible to grasp in advance the characteristics, that is, the SN ratio based on the knocking signal (S: vibration characteristic of the cylinder head) and the noise signal (N: vibration characteristic of the engine block).

  Here, the correlation between the SN ratio obtained by the vibration transfer characteristic analyzing apparatus 100 and the SN ratio of the actual engine will be described with reference to FIGS. FIG. 9 is a diagram showing the relationship between the various engines obtained by the vibration transfer characteristic analyzing apparatus 100 and the pseudo S / N ratio, and FIG. 10 is a diagram of various engines in a state where the engine is actually driven. It is a figure which shows a real machine SN ratio pass / fail.

  The SN ratio at the time of occurrence of engine knocking obtained by the vibration transfer characteristic analyzer 100 is defined as a pseudo SN ratio, and the SN vibration ratio obtained from actual engine driving is defined as an actual SN ratio. From the engine (A), the engine (B), and the engine (C), the pseudo SN ratio and the actual machine SN ratio were compared.

  As a result of measuring the pseudo S / N ratio of each engine using the engine blocks of the engine (A), the engine (B), and the engine (C) using the vibration transfer characteristic analyzing apparatus 100, FIG. 9 shows. Thus, the pseudo S / N ratio with the best controllability of the engine (A) was obtained, and then the pseudo S / N ratio was obtained in the order of the engine (C) and the engine (B).

  Next, the engine (A), engine (B), and engine (C) are actually driven, signals are picked up by knock sensors, and the actual SN ratio is measured. Show. In the engine (A) and the engine (C), an acceptable SN ratio was obtained, and in the engine (B), an unacceptable SN ratio was obtained. As described above, in the engine (B) having the worst pseudo S / N ratio, the actual S / N ratio is also determined to be unacceptable, and the correlation between the S / N ratio obtained by the vibration transfer characteristic analyzer 100 and the S / N ratio of the actual engine is obtained. Proven to have a relationship.

  A specific configuration of the cylinder head vibration detection sensor 320 will be described with reference to FIG. Here, as described above, in the cylinder head vibration detection sensor 320, it is necessary to accurately measure the transverse vibration component generated in the cylinder head 162, and therefore, it is necessary to pay sufficient attention to its mounting position and angle. For example, if the mounting angle with respect to the cylinder head 162 is inaccurate, a measurement error occurs due to a difference in the vibration vector direction. Therefore, in the present embodiment, the cylinder head vibration detection sensor 320 is attached using the plug hole 162p provided in the cylinder head 162.

  As described above, the cylinder head vibration detection sensor 320 includes the special bolt 301, the metal cube 302, and the sensor 303. Here, when the sensor 303 is attached to the special bolt 301, the accuracy of the attachment angle is required. Therefore, a metal cube 302 (cubic shape) finished with high dimensional accuracy by machining is used as the special bolt 301. Between the sensor 303 and the sensor 303. The special bolt 301 and the metal cube 302 are preferably made of the same material as the cylinder head 162 from the viewpoint of preventing measurement errors.

  Various fixing structures are conceivable for fixing the metal cube 302 to the special bolt 301. 11A is a fixing structure using an adhesive, and FIG. 11B is a fixing structure in which a male screw 305A is provided on the special bolt 301 side, and a female screw 305B is received on the metal cube 302 side. 11 (C), a fixing structure provided with a male screw 305A on the metal cube 302 side and a female screw 305B for receiving the male screw 305A on the special bolt 301 side, an independent male screw (stud bolt) shown in FIG. 11 (D) For example, a fixing structure in which 305A is prepared and a female screw 305B for receiving the male screw 305A is provided on each of the special bolt 301 and the metal cube 302, and the like.

  In addition, since the accuracy of the mounting angle of the sensor 303 is required, the case where the metal cube 302 having a flat surface is provided has been described. However, this mounting structure is merely an example, for example, with respect to the cylinder head 162 When it is possible to satisfy the accuracy of the mounting angle, it is possible to adopt a fixing structure in which the sensor 303 is directly mounted on the cylinder head 162.

  Hereinafter, vibration applied to the engine block 160 by the vibration device 130 will be described. As shown in FIG. 12, it is assumed that vibration of a sine wave having a predetermined frequency and a predetermined amplitude is continuously applied to engine block 160.

  The vibration measured by the cylinder block vibration detection sensor 310 provided in the cylinder bore 161A close to the excitation point to which this vibration is applied becomes a sine wave that appears continuously without the vibration being attenuated, as shown in FIG. .

  Similarly, the vibration measured by the cylinder block vibration detection sensor 310 provided in the cylinder bore 161A far from the excitation point becomes a sine wave that appears continuously without the vibration being attenuated, as shown in FIG. The vibration in the cylinder bore 161A far from the excitation point has a smaller amplitude than the vibration in the cylinder bore 161A near the excitation point.

  However, when knocking actually occurs, the vibration is attenuated. Further, the vibration attenuation rate becomes larger as the distance transmitted by the vibration is longer. The vibration characteristics measured by the cylinder block vibration detection sensor 310 when the engine block 160 is continuously vibrated do not match the vibration characteristics.

  Therefore, in the present embodiment, as shown in FIG. 15, when knocking actually occurs, the engine block 160 is vibrated for a time t determined as a time during which vibration due to knocking continues. Further, the engine block 160 is vibrated so that the given vibration is attenuated at a damping rate determined as the damping rate of the vibration caused by knocking.

  Here, the time t when the engine block 160 is vibrated, that is, the time t when the vibration continues when knocking actually occurs is measured data obtained by operating the engine so that knocking occurs by experiment or the like. It is determined from.

  The time t during which vibration continues when knocking occurs is determined by the following equation (1), for example, where r is the engine speed and α ° CA (Crank Angle) is the crank angle at which knocking occurs.

t = (250 × α) / (3 × r) (1)
Similarly, the damping rate of vibration applied to engine block 160 is determined from measurement data obtained by operating the engine so that knocking occurs by experiment or the like. The damping rate of vibration applied to the engine block 160 is determined by the following equation (2), for example, where the crank angle is θ and the coefficient is β (for example, β = 0.1).

Decay rate = exp (−β × θ) (2)
A cylinder block vibration detection sensor 310 provided in the cylinder bore 161A close to the excitation point when vibration attenuated at the attenuation rate obtained from equation (2) is applied to the engine block 160 for the time obtained from equation (1). As shown in FIG. 16, the vibration measured by is attenuated as time elapses.

  Similarly, the vibration measured by the cylinder block vibration detection sensor 310 provided in the cylinder bore 161A far from the excitation point attenuates as time passes as shown in FIG. The vibration in the cylinder bore 161A far from the excitation point has a smaller amplitude and a higher attenuation rate than the vibration in the cylinder bore 161A close to the excitation point.

  Thereby, it is possible to obtain a vibration simulating a state in which knocking has occurred in the engine. By obtaining the pseudo S / N ratio based on such vibration and analyzing the vibration transfer characteristic when the engine block 160 is knocked, the vibration transfer characteristic can be analyzed in accordance with the actual driving state. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  In addition, since the time t for applying vibration to the engine block 160 is determined according to the engine speed r, the vibration transfer characteristic can be analyzed for each engine speed r.

  As described above, according to the vibration transmission characteristic analysis device for an engine block according to the present embodiment, the engine block is vibrated for a time t determined as a time during which vibration continues when knocking actually occurs. . Using the cylinder block vibration detection sensor and the cylinder head vibration detection sensor, a vibration signal generated in the cylinder block and a vibration signal generated in the cylinder head are picked up. The vibration signal and the vibration signal are input to a computer, and the vibration transfer characteristic when the engine block knocks is analyzed. Thereby, it is possible to obtain a vibration simulating a state in which knocking has occurred in the engine. Therefore, it is possible to analyze the vibration transfer characteristics in accordance with the actual driving state. As a result, the analysis accuracy of vibration transfer characteristics can be improved.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is an overall perspective view showing a configuration of a vibration transfer characteristic analyzing apparatus for an engine block and a computer. It is a side view which shows the structure of the vibration transfer characteristic analysis apparatus of an engine block. It is a schematic diagram which shows the structure of a high precision height adjustment mechanism. It is a schematic cross section which shows the internal structure of an engine block. It is an expanded sectional view of a cylinder head. FIG. 6 is a view taken along line VI in FIG. 5. It is the schematic diagram which illustrated the vibration which arises in a cylinder block, and the vibration which arises in a cylinder head. It is a figure which shows the relationship between the signal intensity | strength in knocking generation | occurrence | production ignition timing, and knocking generation frequency. It is a figure which shows the relationship between various engines and the pseudo | simulation SN ratio obtained by the vibration transfer characteristic analyzer. It is a figure which shows the actual machine SN ratio acceptance in various engines in the state which actually driven the engine. It is a figure which shows the specific structure of a cylinder head vibration detection sensor. It is a figure which shows the sine wave which continues continuously. It is FIG. (1) which shows the vibration measured by a cylinder block vibration detection sensor. It is a figure (the 2) which shows the vibration measured by a cylinder block vibration detection sensor. It is a figure which shows the vibration given to an engine block. FIG. 6 is a third diagram illustrating vibrations measured by a cylinder block vibration detection sensor. FIG. 6 is a diagram (part 4) illustrating vibration measured by a cylinder block vibration detection sensor;

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 Vibration transfer characteristic analysis apparatus, 130 Excitation apparatus, 160 Engine block, 161 Cylinder block, 161A Cylinder bore, 162 Cylinder head, 163 Knock sensor mounting boss, 164 Piston, 310 Cylinder block vibration detection sensor, 320 Cylinder head vibration detection sensor

Claims (6)

A vibration transmission characteristic analysis device for an engine block, which is used to vibrate an engine block including a cylinder head and a cylinder block having a cylinder bore and analyze vibration transmission of the engine block,
A vibration exciter connected to the engine block and configured to vibrate the engine block for a predetermined time as a vibration generation time caused by knocking;
A cylinder block vibration measuring instrument disposed on the inner surface of the cylinder bore for measuring vibration;
A vibration transmission characteristic analysis device for an engine block including a cylinder head vibration measuring device that is disposed on an inner surface of the cylinder head and measures vibration.   2. The vibration transfer characteristic analysis device for an engine block according to claim 1, wherein the vibration device gives vibration to the engine block for a predetermined time with a predetermined attenuation rate as a vibration attenuation rate due to knocking. .   The engine block according to claim 1 or 2, wherein the cylinder block vibration measuring device is disposed at a position corresponding to a position of the piston when vibration is generated in the cylinder block by a piston disposed in the cylinder bore. Vibration transfer characteristic analyzer. A method for analyzing vibration transmission characteristics of an engine block comprising a cylinder head and a cylinder block having a cylinder bore,
Applying vibration to the engine block for a predetermined time as a time when vibration due to knocking occurs;
Measuring the vibration of the inner surface of the cylinder bore;
Measuring the vibration of the cylinder head;
Analyzing vibration transmission of the cylinder block based on vibration of the inner surface of the cylinder bore and vibration of the cylinder head.   5. The engine according to claim 4, wherein the step of applying vibration to the engine block includes the step of applying vibration to the engine block for a predetermined time at a predetermined attenuation rate as an attenuation rate of vibration caused by knocking. Block vibration transfer characteristic analysis method.   The step of measuring the vibration of the inner surface of the cylinder bore is a cylinder disposed on the inner surface of the cylinder bore at a position corresponding to the position of the piston when vibration is generated in the cylinder block by the piston disposed in the cylinder bore. 6. The method for analyzing vibration transmission characteristics of an engine block according to claim 4 or 5, further comprising the step of measuring vibration with a block vibration measuring device.

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