JP2008026062A - Vibration transmission characteristic analyzer for engine block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration transmission characteristic analyzer for an engine block capable of reducing cost required for the vibration transmission characteristic analyzer without requiring high connection position accuracy in connection between the engine block and an excitation device. <P>SOLUTION: A knocking sensor 100 is mounted as the excitation device on a knock sensor mounting boss 163 on the inner surface of a cylinder bore 161A. A prescribed voltage is applied to the knocking sensor 100 by using a computer 200, and high-frequency vibration of 10 kHz or higher having strong directivity is applied to the engine block 160. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement in an apparatus for analyzing vibration transmission characteristics of an engine block.

  An engine block vibration transfer characteristic analysis apparatus and a vibration transfer characteristic analysis method using the vibration transfer characteristic analysis apparatus in an engine are disclosed in the following Patent Document 1 (Japanese Patent Laid-Open No. 2004-239696) and Patent Document 2 (Japanese Patent Laid-Open No. 2005). -265541) and Patent Document 3 (Japanese Patent Laid-Open No. 2005-300524).

  FIG. 2 and FIG. 3 show an engine block vibration transfer characteristic analyzing apparatus disclosed in Patent Documents 2 and 3. FIG. In this vibration transfer characteristic analyzing apparatus 2, an engine block 160 whose vibration transfer characteristic is to be analyzed and a vibration exciter 130 for applying predetermined vibration to the engine block 160 are disposed on the surface plate 110. ing.

  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 shown in FIG. 3, the engine block 160 includes a cylinder block 161 having a cylinder bore and a cylinder head 162, and a vibration shaft 140 (see FIG. 2) of the vibration device 130 is a knock provided in the cylinder block 161. It is connected to the sensor mounting boss 163. This knock sensor mounting boss 163 is a cylindrical protrusion for mounting a knock sensor that detects the occurrence of knocking in an actual engine.

  A cylinder block vibration detection sensor 310 is disposed at a position of the cylinder block 161 facing the knock sensor mounting boss 163 on the inner surface of the cylinder bore 161A. A cylinder head vibration detection sensor 320 is disposed in the plug hole 162p provided in the cylinder head 162.

  In the vibration transfer characteristic analysis method using this vibration transfer characteristic analysis device, a response signal when a high-frequency vibration of 10 kHz or more having strong directivity is applied to the engine block 160 by the vibration device 130 is used as a cylinder block vibration measurement sensor. By picking up the vibration signals 1 and 2 by 310 and the cylinder head vibration measurement sensor 320, the vibration characteristics of the cylinder block 161 and the vibration characteristics of the cylinder head 162 can be grasped. As a result, the vibration signals 1 and 2 are analyzed using the computer 200, and a knock signal (S: vibration characteristic of the cylinder head) and a noise signal (N: vibration characteristic of the engine block) are analyzed as vibration transmission characteristics of the engine block 160. The SN ratio is obtained.

  As described above, in the engine block vibration transfer characteristic analyzing apparatus disclosed in Patent Documents 1-3, high-frequency vibration having strong directivity is applied to the engine block 160 from the vibration apparatus 130 via the vibration shaft 140. Yes. Therefore, high attachment accuracy is required in attaching the vibration device 130 to the surface plate 110 and connecting the vibration shaft 140 to the knock sensor attachment boss 163. As a result, the skill of the operator and considerable time are required for this connection work.

  Further, when the vibration shaft 140 is connected to the knock sensor mounting boss 163, position adjustment in units of several tens of μm is required, so that an expensive high-precision height adjustment mechanism 120 is required.

Furthermore, when the engine block, which is the object to be vibrated, becomes larger, the vibration device also needs to be enlarged. However, in order to avoid interference between the engine block and the vibration device, it is necessary to design the vibration device. This may cause an increase in the cost of the vibrating device.
JP 2004-239696 A JP 2005-265541 A JP-A-2005-300524

  The problem to be solved by the present invention is that, in the vibration transmission characteristic analysis device for an engine block, a high connection position accuracy is required for the connection between the engine block and the vibration device, and the vibration transmission characteristic analysis device has a large cost. Is necessary. Therefore, an object of the present invention is to provide a vibration transfer characteristic analysis device for realizing a vibration transfer characteristic analysis method for an engine block, in which the connection between the engine block and the vibration exciter does not require high connection position accuracy. An object of the present invention is to provide an engine block vibration transfer characteristic analyzing apparatus capable of reducing the cost required for the vibration transfer characteristic analyzing apparatus.

  In the vibration transmission characteristic analyzing apparatus for an engine block according to the present invention, an engine used for analyzing vibration transmission of the engine block by exciting an engine block including a cylinder head and a cylinder block having a cylinder bore. A vibration transmission characteristic analyzing apparatus for a block, wherein a cylinder block vibration measuring device disposed in a region corresponding to a combustion chamber on an inner surface of the cylinder bore, and a cylinder head facing the combustion chamber and disposed on an inner surface of the cylinder head A vibration measuring device and a vibration device connected to a predetermined position of the engine block and applying a predetermined vibration to the engine block are provided.

  The cylinder block has a knock sensor mounting boss for mounting a knock sensor for detecting the occurrence of knocking, and the vibration exciter is mounted on the knock sensor mounting boss and applies the voltage to the engine block. Is a knocking sensor that gives a predetermined vibration to the sensor.

  According to the vibration transmission characteristic analysis device for an engine block based on the present invention, a knocking sensor is used as the vibration device, and a predetermined vibration is applied to the engine block by applying a voltage to the knocking sensor. Thus, by using the knock sensor as the vibration device, it is possible to attach the vibration device to the engine block with high accuracy by using the knock sensor mounting boss provided with high accuracy in advance. Further, by applying a voltage to the knocking sensor, it is possible to give a high directivity high frequency vibration of 10 kHz or more to the engine block.

  As a result, it is possible to realize a highly accurate vibration transfer characteristic analysis method without using an expensive vibration device as described above. In addition, also in attaching the vibration device, the knocking sensor can be easily attached using the knock sensor attachment boss. Furthermore, it is not necessary to design a new vibration device even when the engine is enlarged.

  As a result, in the connection between the engine block and the vibration device, the vibration transmission characteristics of the engine block that can reduce the cost required for the vibration transmission characteristic analyzer without requiring high connection position accuracy. An analysis device can be provided.

  Hereinafter, an engine block vibration transfer characteristic analyzer according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a conceptual diagram showing the structure of an engine block vibration transfer characteristic analyzer according to the present embodiment. In the embodiment, the same or corresponding parts as those in the background art are denoted by the same reference numerals, and redundant description may not be repeated.

  As shown in FIG. 1, the vibration transmission characteristic analysis apparatus for an engine block according to the present embodiment vibrates an engine block 160 including a cylinder head 162 and a cylinder block 161 having a cylinder bore 161A. It is used to analyze transmission.

  A cylinder block vibration detection sensor 310 as a cylinder block vibration measuring device is disposed at a position of the cylinder block 161 facing the knock sensor mounting boss 163 on the inner surface of the cylinder bore 161A. A cylinder head vibration detection sensor 320 as a cylinder head vibration measuring device is disposed in the plug hole 162p provided in the cylinder head 162. In an actual engine, a piston 164 that slides up and down is disposed in the cylinder bore 161A, and the position where the cylinder block vibration detection sensor 310 is disposed is disposed in a region corresponding to the combustion chamber A on the inner surface of the cylinder bore. Is done.

  A knock sensor 100 is attached to the knock sensor mounting boss 163 on the inner surface of the cylinder bore 161A as a vibration device. Since knock sensor mounting boss 163 is provided at a high accuracy position, it is possible to attach the vibration device to engine block 160 with high accuracy. As the knocking sensor 100, a non-resonant sensor using a piezo element or the like is used.

(Knock vibration analysis method)
Specifically, the vibration analysis method of the engine block 160 at the time of occurrence of knocking using the vibration transfer characteristic analyzing apparatus 1 having the above-described configuration is a knocking signal (S: cylinder head vibration) as the vibration transfer characteristic of the engine block 160. Characteristics) and a method for obtaining an S / N ratio based on noise signals (N: vibration characteristics of the engine block). First, a predetermined voltage is applied to the knocking sensor 100, which is a vibration device, using the computer 200, and high-frequency vibration of 10 kHz or more with strong directivity is applied to the engine block 160.

  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.

  As described above, according to the vibration transfer characteristic analyzing apparatus 1 in the present embodiment, the knocking sensor 100 is used as the vibration exciting device, and a predetermined vibration is applied to the engine block 160 by applying a voltage to the knocking sensor 100. As described above, by using the knocking sensor 100 as the vibration device, the knock sensor mounting boss 163 provided in advance with high accuracy can be used, and the knocking sensor 100 as the vibration device with high accuracy can be attached to the engine block 160. It can be attached. Further, by applying a voltage to knocking sensor 100, it is possible to apply high-frequency vibrations of 10 kHz or more with strong directivity to engine block 160.

  As a result, it is possible to realize a highly accurate vibration transfer characteristic analysis method without using an expensive vibration device as shown in the background art. Further, also in the attachment of the knocking sensor 100 that is the vibration device, the knocking sensor 100 can be easily attached to the engine block 160 using the knock sensor attachment boss 163, and the work can be simplified. Furthermore, it is not necessary to design a new vibration device even when the engine is enlarged.

  As a result, in the connection between the engine block 160 and the vibration generator, the vibration transmission of the engine block that can reduce the cost required for the vibration transmission characteristic analyzer without requiring high connection position accuracy. The characteristic analysis apparatus 1 can be provided.

  Note that the arrangement positions of the cylinder block vibration detection sensor 310 and the cylinder head vibration detection sensor 320 are not limited to the positions shown in FIG. 1, and may be changed as appropriate according to the purpose of the vibration transfer characteristic analysis to be performed. It is what is done.

  As mentioned above, although each embodiment based on this invention was described, it should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a conceptual diagram which shows the structure of the vibration transmission characteristic analysis apparatus of the engine block in embodiment based on this invention. It is a conceptual diagram which shows the structure of the vibration transfer characteristic analysis apparatus of the engine block in background art. It is a conceptual diagram which shows the internal structure of the engine block in background art.

Explanation of symbols

  100 knocking sensor, 160 engine block, 161 cylinder block, 161A cylinder bore, 162 cylinder head, 162p plug hole, 163 knock sensor mounting boss, 164 piston, 200 computer, 310 cylinder block vibration detection sensor, 320 cylinder head vibration detection sensor.

Claims (1)

A vibration transmission characteristic analysis device for an engine block, which is used to analyze vibration transmission of the engine block by exciting an engine block including a cylinder head and a cylinder block having a cylinder bore,
A cylinder block vibration measuring instrument disposed in a region corresponding to the combustion chamber on the inner surface of the cylinder bore;
A cylinder head vibration measuring instrument facing the combustion chamber and disposed on the inner surface of the cylinder head;
A vibration device connected to a predetermined position of the engine block and applying a predetermined vibration to the engine block;
The cylinder block has a knock sensor mounting boss for mounting a knocking sensor that detects the occurrence of knocking,
The vibration transmission characteristic analysis device for an engine block, which is a knocking sensor that is attached to the knock sensor mounting boss and applies a predetermined vibration to the engine block by applying a voltage.

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