JP5978862B2 - Bonded surface dynamic characteristic measuring apparatus and bonded surface dynamic characteristic measuring method - Google Patents

Description

  The present invention relates to a combined surface dynamic characteristic measuring apparatus and a combined surface dynamic characteristic measuring method.

  Conventionally, in order to improve the analysis accuracy when an analysis object in which a plurality of parts are combined is converted into a finite element model and analyzed by the finite element method (FEM), There is known a method of arranging a spring element and a damping element at the joint of the two, but in the current technology, it is difficult to obtain a variable to be given to the spring element and the damping element by calculation. The analysis is performed using a finite element model in which the joints between parts are joined by sharing nodes.

JP 2004-070397 A JP 2006-350475 A

  However, since such a finite element model behaves as a rigid connection structure that is far from the structure of the actual machine where rigidity and damping due to coupling exist, the analysis value by the finite element method greatly deviates from the actual measurement value, The analysis accuracy was a factor.

  Therefore, there is a strong demand for practical use of a technique that enables highly accurate identification of variables given to a spring element and a damping element and that arranges the spring element and the damping element at a joint between components.

  Therefore, an object of the present invention is to increase the variable given to the spring element and the damping element that represent the characteristics of the coupling while coupling the plurality of parts when modeling the analysis object in which the plurality of parts are coupled. It is an object of the present invention to provide a combined plane dynamic characteristic measuring apparatus and a combined plane dynamic characteristic measuring method that can be accurately identified.

  In order to achieve this object, the present invention provides a spring element and a damping element that combine a plurality of parts and express characteristics of the connection when an analysis object in which a plurality of parts are combined is modeled as a finite element. A coupled surface dynamic characteristic measuring apparatus for identifying a variable to be given to an element, and sandwiching a second test piece simulating a second part with a first test piece simulating a first part, and A surface pressure applying means for applying a predetermined surface pressure to the bonding surface between the first test piece and the second test piece; and the surface pressure applied to the bonding surface by the surface pressure applying means. Excitation force applying means for applying a preset excitation force to the two test pieces, and the first test piece and the second test piece when the excitation force is applied by the excitation force applying means. The relative displacement measuring means for measuring the relative displacement with the excitation force applying means. Processing means for identifying a variable to be given to the spring element and the damping element for each surface pressure applied by the surface pressure applying means based on the excitation force and the relative displacement measured by the relative displacement measuring means A coupled surface dynamic characteristic measuring device.

  The surface state of the first test piece is the same as the surface state of the first component, and the surface state of the second test piece is preferably the same as the surface state of the second component.

  The processing means identifies a spring constant to be given to the spring element based on the excitation force applied by the excitation force application means and the relative displacement measured by the relative displacement measurement means, and the identified spring A constant and a delay angle of relative displacement measured by the relative displacement measuring unit with respect to the excitation force applied by the excitation force applying unit and an excitation angular frequency of the excitation force applied by the excitation force applying unit. Based on the above, it is preferable to identify an attenuation coefficient to be given to the attenuation element.

  Further, according to the present invention, when an analysis object in which a plurality of parts are combined is formed into a finite element model, a variable given to the spring element and the damping element representing the characteristics of the connection is identified while the plurality of parts are combined. A method for measuring a coupling surface dynamic characteristic for sandwiching a second test piece simulating a second part with a first test piece simulating a first part, and the first test piece and the first test piece A step of applying a preset surface pressure to the bonding surface with the test piece of 2, and a step of applying a preset excitation force to the second test piece in a state where the surface pressure is applied to the bonding surface; Based on the step of measuring the relative displacement between the first test piece and the second test piece when an excitation force is applied, and the applied excitation force and the measured relative displacement Identifying a variable to be given to the spring element and the damping element for each measured surface pressure. A mating surface dynamics measurement method.

  The surface state of the first test piece may be the same as the surface state of the first part, and the surface state of the second test piece may be the same as the surface state of the second part.

  In the step of identifying the variable to be given to the spring element and the damping element, the spring constant to be given to the spring element is identified based on the applied excitation force and the measured relative displacement, and the identified spring constant Based on the measured relative displacement delay angle with respect to the applied excitation force and the excitation angular frequency of the applied excitation force, the damping coefficient applied to the damping element may be identified.

  According to the present invention, when an analysis object in which a plurality of parts are combined is formed into a finite element model, the variable given to the spring element and the damping element that combine the plurality of parts and express the characteristics of the connection with high accuracy It is possible to provide a coupled plane dynamic characteristic measuring apparatus and a coupled plane dynamic characteristic measuring method that can be identified.

It is a side view which shows the combined surface dynamic characteristic measuring apparatus which concerns on this invention. It is the sectional view on the AA line of FIG. FIG. 3 is a sectional view taken along line B-B in FIG. 2. It is a figure which shows an example of a finite element model. It is a figure which shows the finite element model which concerns on this invention. It is a figure which shows the finite element model which concerns on a prior art. It is a figure which shows the relationship between an exciting force and relative displacement. It is a figure which shows the relationship between the spring constant with respect to an average surface pressure, and a damping coefficient. It is a figure which shows the modes 1-4.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  As shown in FIGS. 1 to 3, the coupled surface dynamic characteristic measuring apparatus 10 according to the present embodiment is a first test piece 11 simulating a first component and a second test piece simulating a second component. The surface pressure is applied to the joint surface between the first test piece 11 and the second test piece 12, and the surface pressure is applied to the joint surface by the surface pressure imparting means 13. Excitation force applying means 14 for applying a preset excitation force to the second test piece 12 in the applied state, and the first test piece when the excitation force is applied by the excitation force applying means 14 11 based on the relative displacement measuring means 15 for measuring the relative displacement between the second test piece 12 and the excitation force applied by the excitation force applying means 14 and the relative displacement measured by the relative displacement measuring means 15. For each surface pressure applied by the surface pressure applying means 13, a spring element (spring) and a damping element (double Shupotto) and gives variable, i.e. the processing means for identifying a spring constant and damping coefficient (not shown), characterized in that it comprises a.

  In the present embodiment, as an example, as shown in FIG. 4, a finite element model is generated using an engine single cylinder in which a plurality of parts such as a cylinder head 41, a cylinder block 42, and a ladder frame 43 are combined as an analysis object. Explain the case.

  As shown in FIG. 5, the coupled surface dynamic characteristic measuring apparatus 10 combines a plurality of parts and represents a coupling characteristic when a finite element model of an analysis object in which a plurality of parts are coupled is represented. And a damping coefficient to be given to the damping element 52 and a damping coefficient.

  Conventionally, since it is difficult to obtain the spring constant and the damping coefficient given to the spring element 51 and the damping element 52 by calculation, the joint between the parts is shared by the node 61 as shown in FIG. In other words, the analysis was performed as a joint by knots, that is, a node joint.

  However, the finite element model in which the joints between the parts are connected to each other behaves as a rigid connection structure that is far from the structure of the actual machine where the rigidity and damping due to the connection exist. The result was a large difference, which was a factor that deteriorated the analysis accuracy.

  In order to solve such a problem and to model the coupling portion between the parts with the spring element 51 and the damping element 52, the spring constant and the damping coefficient given to the spring element 51 and the damping element 52 are highly accurate. The invention invented for the identification is the combined plane dynamic characteristic measuring device 10.

  The first test piece 11 is formed of the same material as the first part (for example, the cylinder head 41), and the second test piece 12 is the same material as the second part (for example, the cylinder block 42). Formed with. Further, the surface state of the first test piece 11 is preferably the same as the surface state of the first component, and the surface state of the second test piece 12 is preferably the same as the surface state of the second component. .

  This is because the spring constant and the damping coefficient change due to the difference in the applied surface pressure, while the mechanical properties unique to the material such as the Young's modulus and Poisson's ratio of the first and second parts forming the coupling portion. In addition, it is also affected by surface conditions such as surface roughness and flatness.

  For these reasons, it is most desirable that the first test piece 11 and the second test piece 12 are actually cut out from the first part and the second part that form the coupling portion of the actual machine. However, the coupling portion may be faithfully modeled from information such as drawings of the first component and the second component.

  The surface pressure applying means 13 includes a linear guide rail 16 provided along a direction perpendicular to the coupling surface, a linear guide 17 that travels on the linear guide rail 16, and the first test piece 11 and the first test piece 11. The surface pressure applying portion 18 that sandwiches the two test pieces 12 to apply a surface pressure to the coupling surface, and is attached to the surface pressure applying portion 18 via a thrust roller bearing 19 and the surface pressure from both sides of the measuring instrument main body 20. A bolt 21 for applying a load to the applying unit 18 and a load meter 22 for measuring the load applied by the bolt 21 are provided.

  The surface pressure applied to the bonding surface can be obtained by dividing the measured value of the load cell 22 by the bonding area between the first test piece 11 and the second test piece 12.

  In order to apply a preset surface pressure to the bonding surface using the surface pressure applying means 13, the measured value of the load cell 22 is divided by the bonding area between the first test piece 11 and the second test piece 12. What is necessary is just to adjust the load applied by rotating the volt | bolt 21 so that a value may become the value of the preset surface pressure.

  In addition, how to obtain | require the surface pressure provided to a joint surface is not limited to this, For example, you may obtain | require using a pressure sensitive paper.

  The excitation force applying means 14 is attached to the center portion of the second test piece 12 via the stud bolt 23 and applies a fluctuating load in a direction parallel to the coupling surface in the second test. A linear single-axis robot 24 that applies an excitation force to the piece 12 and a load meter 25 that measures a fluctuating load applied by the linear single-axis robot 24 are provided.

  The excitation force applied to the second test piece 12 can be obtained from the measurement value of the load meter 25.

  In order to apply a preset excitation force to the second test piece 12 using the excitation force applying means 14, linear measurement is performed so that the measurement value of the load cell 25 becomes a preset excitation force value. The excitation waveform and the excitation angular frequency of the single axis robot 24 may be adjusted.

  The relative displacement measuring unit 15 is placed on the XY linear stage 26 and measures the displacement of the first test piece 11 when the excitation force is applied by the excitation force applying unit 14. A sensor 27 and a second displacement sensor 28 that is mounted on the XY linear stage 26 and measures the displacement of the second test piece 12 when the excitation force is applied by the excitation force applying means 14. .

  The first displacement sensor 27 and the second displacement sensor 28 are, for example, capacitive displacement sensors.

  The relative displacement between the first test piece 11 and the second test piece 12 can be obtained by subtracting the measurement value of the second displacement sensor 28 from the measurement value of the first displacement sensor 27.

  The processing unit includes, for example, a computer equipped with a microprocessor, a memory, and the like, and based on the excitation force applied by the excitation force applying unit 14 and the relative displacement measured by the relative displacement measuring unit 15, the spring element 51 is identified, and the relative displacement delay angle measured by the relative displacement measuring means 15 with respect to the identified spring constant and the excitation force applied by the excitation force applying means 14 and the excitation force applying means 14. The damping coefficient to be given to the damping element 52 is identified based on the excitation angular frequency of the excitation force applied by.

  Next, a method for measuring a combined surface dynamic characteristic using the combined surface dynamic characteristic measuring apparatus 10 will be described.

  In the coupled surface dynamic characteristic measurement method according to the present embodiment, when an analysis object in which a plurality of parts are coupled is modeled as a finite element model, the spring element 51 and the damping that represent the coupling characteristics are coupled to the plurality of parts. This is for identifying the spring constant and damping coefficient applied to the element 52, and sandwiching the second test piece 12 simulating the second part with the first test specimen 11 simulating the first part. The step of applying a predetermined surface pressure to the joint surface between the first test piece 11 and the second test piece 12 and the second test piece 12 preset with the surface pressure applied to the joint surface A step of applying the applied excitation force, a step of measuring relative displacement between the first test piece 11 and the second test piece 12 when the excitation force is applied, and the applied excitation force and measurement. The spring element 51 and the damping element 52 for each applied surface pressure based on the applied relative displacement. A step of identifying the Erubane constant and damping coefficient, characterized in that it comprises a.

  It is desirable that the surface state of the first test piece 11 is the same as the surface state of the first component, and the surface state of the second test piece 12 is the same as the surface state of the second component.

  In the step of identifying the spring constant and damping coefficient applied to the spring element 51 and the damping element 52, the spring constant applied to the spring element 51 is identified based on the applied excitation force and the measured relative displacement. The damping coefficient to be given to the damping element 52 is identified based on the identified spring constant, the delay angle of the measured relative displacement with respect to the applied excitation force, and the excitation angular frequency of the applied excitation force.

For example, as shown in FIG. 7, a sinusoidal waveform having an excitation angular frequency ω is applied to the second test piece 12 by the excitation force applying unit 14 in a state where the surface pressure is applied to the coupling surface by the surface pressure applying unit 13. When the excitation force F = F ₀ sin (ωt) is applied, the relative displacement X is delayed with respect to the excitation force F if there is damping on the coupling surface. If the delay angle is defined as δ, the relative displacement is defined as X = X ₀ sin (ωt−δ). Here, F ₀ is the maximum excitation force, X ₀ is the maximum relative displacement, and t is time.

  The spring constant k and the damping coefficient C in this case are defined by the following formula (1).

  The spring constant k and the damping coefficient C change as shown in FIG. 8 with respect to the average surface pressure of the coupling surface.

  That is, the surface pressure imparted to the coupled surface is changed by the surface pressure imparting means 13 using the coupled surface dynamic characteristic measuring device 10, and after completing the diagram as shown in FIG. Based on the pressure distribution, an appropriate spring constant k and damping coefficient C to be given to the spring element 51 and the damping element 52 between the nodes of the finite element model are identified.

  If the spring constant k and the damping coefficient C are identified from the measurement result by the coupling surface dynamic characteristic measuring device 10, the coupling area between the first test piece 11 and the second test piece 12 and a plurality of parts of the actual machine The spring element 51 and the damping element 52 to which the spring constant k and the damping coefficient C identified between the nodes of the finite element model are given may be arranged in accordance with the ratio of the coupling area between them.

  This makes it possible to create a finite element model that has characteristics that are very close to those of the actual machine. Can be improved.

  As described above, according to the present invention, when an analysis object in which a plurality of parts are combined is formed into a finite element model, a spring element and a damping element that combine the plurality of parts and express the characteristics of the connection are provided. It is possible to provide a coupled plane dynamic characteristic measuring apparatus and a coupled plane dynamic characteristic measuring method capable of identifying a variable given to the above with high accuracy.

  Next, examples of the present invention will be described.

  As shown in FIGS. 9A to 9D, the engine single cylinder of FIG. 4 was modeled as a finite element, and the natural frequencies of the four modes from the primary mode to the quaternary mode were analyzed. The analysis results are shown in Table 1.

  Here, the embodiment is a case where the finite element modeling is performed by arranging the spring element and the damping element whose spring constant and damping coefficient are identified by the coupling surface dynamic characteristic measuring device 10 at the coupling portion of a plurality of parts. The comparative example is a case where finite element modeling is performed by using a joint portion of a plurality of parts as a node joint.

  As can be seen from Table 1, a finite element model in which spring elements and damping elements are arranged at the joints of a plurality of parts as compared to the comparative example in which the joints of a plurality of parts are jointed as node joints. The difference between the analysis value and the actual measurement value is smaller in the embodiment in which the conversion is performed.

  From the above results, it was proved that excellent analysis accuracy can be obtained by modeling the coupling portion with the spring element and the damping element given the spring constant and damping coefficient identified by the present invention.

DESCRIPTION OF SYMBOLS 10 Coupling surface dynamic characteristic measuring apparatus 11 1st test piece 12 2nd test piece 13 Surface pressure provision means 14 Excitation force provision means 15 Relative displacement measurement means 16 Linear guide rail 17 Linear guide 18 Surface pressure provision part 19 Thrust roller Bearing 20 Measuring instrument body 21 Bolt 22 Load meter 23 Stud bolt 24 Linear single-axis robot 25 Load meter 26 XY linear stage 27 First displacement sensor 28 Second displacement sensor

Claims (6)

Coupling surface motion characteristics for identifying a variable given to a spring element and a damping element that combine the plurality of parts and represent the characteristics of the coupling when modeling an analysis object in which a plurality of parts are coupled A measuring device,
The second test piece simulating the second part is sandwiched between the first test piece simulating the first part, and the bonding surface between the first test piece and the second test piece is set in advance. Surface pressure applying means for applying surface pressure;
An excitation force applying means for applying a preset excitation force to the second test piece in a state in which a surface pressure is applied to the coupling surface by the surface pressure applying means;
Relative displacement measuring means for measuring relative displacement between the first test piece and the second test piece when the excitation force is applied by the excitation force applying means;
Based on the excitation force applied by the excitation force applying means and the relative displacement measured by the relative displacement measuring means, the spring element and the damping element for each surface pressure applied by the surface pressure applying means. And a processing means for identifying a variable to be given to
A combined plane dynamic characteristic measuring device comprising:   The surface state of the first test piece is the same as the surface state of the first part, and the surface state of the second test piece is the same as the surface state of the second part. The combined surface dynamic characteristic measuring device described in 1.   The processing means identifies a spring constant to be given to the spring element based on the excitation force applied by the excitation force application means and the relative displacement measured by the relative displacement measurement means, and the identified spring A constant and a delay angle of relative displacement measured by the relative displacement measuring unit with respect to the excitation force applied by the excitation force applying unit and an excitation angular frequency of the excitation force applied by the excitation force applying unit. The coupling surface dynamic characteristic measuring device according to claim 1, wherein the damping coefficient given to the damping element is identified based on Coupling surface motion characteristics for identifying a variable given to a spring element and a damping element that combine the plurality of parts and represent the characteristics of the coupling when modeling an analysis object in which a plurality of parts are coupled Measuring method,
The second test piece simulating the second part is sandwiched between the first test piece simulating the first part, and the bonding surface between the first test piece and the second test piece is set in advance. Applying a surface pressure;
Applying a preset excitation force to the second test piece in a state in which a surface pressure is applied to the coupling surface;
Measuring a relative displacement between the first test piece and the second test piece when an excitation force is applied;
Identifying a variable to be given to the spring element and the damping element for each applied surface pressure based on the applied excitation force and the measured relative displacement;
A method for measuring a coupled surface dynamic characteristic, comprising:   The surface state of the first test piece is the same as the surface state of the first part, and the surface state of the second test piece is the same as the surface state of the second part. Bonded surface dynamics measurement method.   In the step of identifying the variable to be given to the spring element and the damping element, the spring constant to be given to the spring element is identified based on the applied excitation force and the measured relative displacement, and the identified spring constant The damping coefficient to be given to the damping element is identified based on the measured relative displacement delay angle with respect to the applied excitation force and the excitation angular frequency of the applied excitation force. The bonded surface dynamic characteristic measurement method described.