JP2000136978A - Shock/vibration testing method and device used for the same, and mounting mechanism of vibration sensor used for shock/vibration-testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting mechanism of a vibration sensor used by a shock/ vibration-testing device that is applicable as a pseudo earthquake-testing device where a shock stress wave being similar to an inland earthquake can be effectively added, an injection-molding device, or the like. SOLUTION: This mounting mechanism 20 comprises a casing 21 that is fixed onto the lower surface of a vibration table 7, a shock vibration absorber 22 such as air bellows or an anti-vibration rubber or the like being mounted onto a casing bottom plate 211 in the casing 21, a cylinder-mounting plate 23 being mounted onto the absorber 22, an air cylinder 24 being installed onto the mounting plate 23, a square-shaped sensor mounting plate 25 that is mounted the tip of a piston shaft 241 of a cylinder, a vibration sensor 16 that is mounted to a guide plate 29 being mounted between a mounting plate 25 and the vibration sensor 16 and the mounting plate 25, and a bottom stopper 27 that is erected on a sensor-fixing plate 26 being fixed onto the upper surface of the sensor 16 and the casing bottom plate 211 below the cylinder- mounting plate 23, and controls the amount of press of the shock vibration absorber 22 being pressed when the cylinder is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock / vibration test method, a shock / vibration test device used in the test method, and a mounting mechanism of a vibration sensor used in the device and the like. The present invention relates to a mechanism for mounting a vibration sensor used in an impact / vibration test device, an injection molding device, or the like that can be applied as a pseudo-earthquake test device capable of effectively applying a stress wave.

[0002]

2. Description of the Related Art Conventionally, a seismic wave has two high frequency components and low frequency components similar to a shock wave. on the other hand,
There are two types of earthquakes: ocean-type earthquakes caused by subduction of the oceanic plate, and direct-type earthquakes that occur just below the land where active faults exist.
In the case of the former oceanic earthquake, since the distance from the earthquake source to the land is far, high frequency components are attenuated, and low frequency becomes a serious problem.

The conventional earthquake countermeasures are modeled on the Great Kanto Earthquake. For example, only earthquake disaster prevention in the Keihin district at an earthquake source caused by the sinking of the Sagami plate is considered. Prior to the Great Hanshin Earthquake, the earthquake was assumed to be an oceanic earthquake caused by the subduction of the oceanic plate, so a slow-period seismic waveform was assumed. The strength test was sufficient.

However, in the case of a direct earthquake such as the Great Hanshin Earthquake, high-frequency components have a large effect, the initial period is short (the period T is almost the same as or smaller than 0.1 s), and the speed is large (the speed υ is large). (Approximately equal to or greater than 10 cm / s), it is difficult to generate this waveform by a method other than solid collision.

In view of this problem, Japanese Patent Application Laid-Open No. 9-292304 discloses a test apparatus capable of performing a low-frequency vibration test continuously after an impact test.

In this prior art, a collision body is caused to collide with a table at a high speed by a hydraulic cylinder, and an impact load is applied to the specimen through the table. After the test, a low-frequency vibration test is performed continuously.

[0007]

However, the prior art has the following problems. That is, in the test device, there are an impact force measurement sensor that detects an impact force, and a vibration detection sensor that detects the low-frequency vibration described above, and each of the sensors measures the impact force and the low-frequency vibration. However, even when an impact force is applied, an impact force is applied to the vibration sensor (acceleration sensor). In particular, since the impact force is applied to the measurement range (± 5G) of the vibration sensor by 200 times or more, the above-mentioned impact force is applied. Impact force (1000
G) has a disadvantage that the vibration sensor is broken and smooth vibration measurement cannot be performed.

On the other hand, even in a vibration sensor attached to an injection molding apparatus, a large impact force of 100 times or more may be applied to a measurement range, and a preferable attachment mechanism of the vibration sensor is required in such an apparatus.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides a shock / vibration test method for testing the strength of a test piece by adding an impact force due to a collision and a vibration acceleration due to a vibrating force to the sensor. It is an object of the present invention to provide a test method and a shock / vibration test apparatus capable of detecting a low-frequency vibration after the action of an impact force smoothly and accurately. It is another object of the present invention to provide a vibration sensor mounting mechanism in which the vibration sensor is not damaged even when an impact force much larger than the measurement range is applied to the front stage. Still another object of the present invention is to provide a vibration sensor mounting mechanism suitably applied to the above-described impact / vibration test apparatus and also to an injection molding machine.

[0010]

According to the first aspect of the present invention,
In a shock / vibration test method for testing the strength of a test piece by adding a shock force due to a collision and a vibration acceleration due to a vibrating force to the test piece, the vibration sensor for measuring the vibration acceleration may be configured such that the shock sensor acts during the action of the shock force due to the collision. The test piece is held apart from the vibration measurement surface, and is tightly fixed to the vibration measurement surface when transmitting the vibration acceleration due to the excitation force to the specimen.

As described above, in a quasi-earthquake test apparatus capable of giving a shock / vibration waveform similar to a direct earthquake, it is necessary to apply a shock stress wave before applying a low frequency vibration wave. When an impact force acts on the vibration sensor (acceleration sensor) measured at the subsequent stage, an impact force much larger than the measurement range is applied, and the vibration sensor is damaged by the impact force (1000 G). During the action of the impact force, the vibration sensor is held in the air at a distance from the vibration measurement surface, so that the impact force does not damage the vibration sensor.
Further, when transmitting the vibration acceleration due to the exciting force to the specimen, the low frequency vibration wave can be transmitted to the vibration sensor accurately and reliably because the vibration acceleration is caused by the vibrating force.

A second aspect of the present invention relates to an apparatus for effectively carrying out the invention, wherein after receiving an impact force due to the collision, a vibration acceleration by an exciting force is transmitted to the specimen. A vibration sensor for detecting vibration in a predetermined coordinate axis direction is attached to the vibration table via a sensor mounting mechanism, and the vibration sensor is held on the sensor mounting mechanism at a distance from the vibration table during an impact force due to a collision. When transmitting vibration acceleration due to a vibrating force to the specimen, a separating means is provided for the vibration sensor to be closely fixed to the vibrating table surface.

According to the invention, the vibration sensor is held apart from the vibrating table during the action of the impact force due to the collision by the separation / contact means, so that the vibration sensor is damaged by the impact force. On the other hand, when transmitting the vibration acceleration due to the excitation force to the specimen, the vibration sensor is closely attached to the excitation table surface, so that the low-frequency vibration wave is accurately and reliably transmitted to the vibration sensor side. I can do it.

According to a third aspect of the present invention, there is provided a vibration sensor mounting mechanism for effectively implementing the above-mentioned invention. However, after a large impact force significantly larger than the vibration measuring range is applied in advance, a predetermined coordinate axis is set. If it is a device that performs directional vibration measurement, it is not only a shock / vibration test device, but also a vibration sensor mounting mechanism that is suitably applied to, for example, an injection molding machine. It is composed of a fixed casing and a vibration sensor mounted in the casing via an impact vibration absorber and cylinder means. The mounting height of the vibration sensor is separated from the vibration measurement surface when the cylinder means is not operated. It is set to a height that is held and tightly fixed to the vibration measurement surface when the cylinder means operates.

In this case, preferably, the connection between the cylinder means and the vibration sensor is performed via a sensor swing preventing means, and the movement of the vibration sensor by the cylinder means. In this case, it is preferable that the sensor is positioned in a predetermined coordinate axis direction so that the sensor can be separated from and connected to the sensor.

The sensor swing preventing means may be any as long as it restricts rotation in a plane perpendicular to the sensor separation / contact direction. For example, in the embodiment described later, the piston shaft 241 is formed of a hexagonal rod. According to this invention, since the rotation of the vibration sensor is restricted in a plane perpendicular to the sensor separation / contact direction by the sensor swing prevention means, the vibration sensor is always positioned in the predetermined coordinate axis direction even if the vibration sensor moves away from the sensor. Adhesion fixation at a position becomes possible.

The invention according to claim 5 is characterized in that stopper means for regulating a pressing amount of the shock vibration absorber pressed when the cylinder means is operated is provided.

The shock vibration absorber is made of a material that is significantly different from the resonance frequency of the impact force. For example, in a quasi-seismic test device similar to a direct earthquake, since the first shock stress wave is 7 to 10 KHz, an air bellows or a vibration-proof rubber having a resonance frequency of about 10 Hz which is much lower than this is used. Is good. When such an impact vibration absorber such as a vibration-proof rubber is used, the impact vibration absorber is unnecessarily compressed by the contact / separation operation by the cylinder means (air cylinder) and deteriorates in a short period of time. Therefore, according to the present invention, unnecessary compression of the impact vibration absorber (anti-vibration rubber) can be avoided by the stopper means, and it is possible to withstand long-term use.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be illustratively described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only.

1 and 2 show a vibration sensor mounting mechanism according to an embodiment of the present invention. FIG. 1 (A) is a plan view, FIG. 1 (B) is a sectional view taken along line BB of FIG. 1 (A), and FIG. FIG. 1 (A)
It is AA sectional drawing of. In FIG.
Reference numeral 0 denotes a casing 21 fixed to the lower surface of the vibration table 7.
And an impact / vibration absorber 22, such as an air bellows or a vibration-proof rubber, mounted on a casing bottom plate 211 in the casing 21, a cylinder mounting plate 23 mounted on the absorber 22, and mounted on the mounting plate 23. Air cylinder 24, a rectangular sensor mounting plate 25 mounted on the tip of a piston shaft 241 of the cylinder 24, a guide plate 29 mounted between the mounting plate 25 and the vibration sensor 16, the mounting plate 25 A vibration sensor 16 attached to the sensor 16 via a guide plate 29, a sensor fixing plate 26 fixed to the upper surface of the sensor 16, and a bottom stopper 27 that regulates the amount of impact vibration absorber 22 pressed when the cylinder is raised. Become.

The casing 21 includes the casing bottom plate 21.
1 and a casing upper plate 21 fixed to the vibration table 7
And a pair of side walls 2 disposed between the bottom plate 211 and the upper plate 212 and located on both left and right sides of the mounting mechanism 20 main body.
A hole 214 is opened at the center of the casing upper plate 212, and the sensor fixing plate 26 can be directly adhered to the lower surface of the vibration table 7 by the hole 214.

The impact vibration absorber 22 is provided in the
Is not particularly limited as long as it is made of a material that is significantly different from the shock frequency at the time of collision with the shock transmission table 2. For example, in the present embodiment, the first shock stress wave is 7-1.
Since the frequency is 0 KHz, an air bellows or a vibration-proof rubber having a resonance frequency of about 10 Hz which is much lower than this is used.

The air cylinder 24 includes the piston shaft 24
Two air connection ports 246 and 247 for raising and lowering 1 are provided, and a rising speed of the vibration sensor 16 can be controlled through a throttle 249 at the lifting return port 246. A rectangular sensor mounting plate 25 is attached to the tip of the piston shaft 241, and a guide plate 29 mounted on the sensor mounting plate 25 is attached to the side wall 2.
By sliding up and down in the inside 13, the vibration sensor 16 can be pressed vertically against the vibration table 7 without tilting.

The mounting height of the vibration sensor 16 from the upper surface of the fixed plate 26 to the lower surface of the vibration table is held at a predetermined gap from the lower surface of the vibration table when the air cylinder 24 is lowered (unlocked). When the air cylinder 24 is raised (locked), the air cylinder 24 is set so as to be tightly fixed to the lower surface of the vibration table. Further, as described above, the bottom stopper 27 for regulating the amount of pressing is provided so that the impact vibration absorber 22 is not unnecessarily compressed as a reaction when the air cylinder 24 is raised.

Next, FIGS. 3 and 4 show an impact / vibration test apparatus in which the vibration sensor mounting mechanism 20 is incorporated.
FIG. 3 is a front view, and FIG. 4 is a sectional view taken along line AA of FIG. FIG.
In the above, a specimen 3 in which a specimen body 31 made of concrete is vertically sandwiched between iron blocks 30 and 30 so as to obtain a shock wave by reflection is installed on the shock transmission table 2. A vibration sensor 40 for measuring an impact force trigger signal is attached to the shock transmission table 2, and the measurement range of the sensor is 600 times or more the measurement range (± 5G) of the Χ, Y, and Z axis sensors 16 described below ( 3000 G or more) so that the impact force on the impact transmission table can be measured sufficiently.

On the other hand, as shown in FIG. 4, the vibrating table 7 is mounted on a pair of horizontal vibrators 11 (11X, 11Y) arranged in the Χ-axis / Y-axis directions indicated by phantom lines, respectively. The two side surfaces of the shaft are in contact with each other, and the lower surfaces on both left and right sides thereof are installed on four vertical vibration exciters 12 arranged diagonally with respect to the center. In the three-dimensional direction. On the lower surface of the excitation table 7, a vibration sensor 16 for detecting vibrations in the coordinate axes of the Χ, Y, and Z axes is mounted via a mounting device 20 of the present invention. It becomes possible.

Returning to the original, openings 7a1 and 7a2 are formed in the center of the vibrating table 7 formed in the shape of a square board in a stepped manner. 8 shock absorbers 8 at 45 ° intervals around
Are provided, and eight hollow fixed cylinders 9 are provided between the mounting positions of the shock absorber. (See FIG. 4) Further, an opening hole 7b is formed in the vibration table 7 above the fixed cylinder 9.

The shock transmission table 2 is placed on the upper surface 7g of the vibration table 7, and around the mounting position of the specimen on the shock transmission table 2, there are formed opening holes 2b corresponding to the eight opening holes 7b. The fixing bolt shaft 10 is inserted through the opening holes 7b and 2b. The fixed bolt shaft 10 extends from the shock transmission table 2 to the vibration table 7, the fixed cylinder 9, and the connection ring 13. The upper end of the fixing bolt shaft 10 protrudes from the upper surface of the impact transmission table 2 as shown in the enlarged circle in the upper part of FIG. 3, and a flange-type fixing nut 2 a is screwed to the upper end of the fixing bolt shaft 10. The flange-type fixing nut 2a is fixed by a mounting bolt 2c, and the fixing bolt shaft 10 and the impact transmission table 2 are integrally fixed. Similarly, the lower end side of the fixing bolt shaft 10 also protrudes from the lower surface of the side end of the connecting ring 13 as shown in the enlarged circle in the lower part of FIG. 3, and is screwed to the connecting ring 13 by a nut 2d. Thus, the shock transmission table 2 and the connection ring 13 are integrally connected by the fixing bolt shaft 10. On the other hand, one end of the shock absorber 8 is
One end is bolted to the connecting ring 13. One end of the fixed cylinder 9 is bolted to the vibration table 7, but the other end is not fixed to the connection ring 13.

As a result, during the shock / vibration test, the connecting table 13 is pushed down by the fixed cylinder 9 to fix the vibration table 7 and the shock transmission table 2 with the bolt shaft 10. Therefore, the specimen 3 moves integrally with the vibration table 7 via the shock transmission table 2.

The launching device 6 is connected to a hydraulic drive device (not shown) via a pipe, and the collision body 1 made of iron and formed in a cylindrical shape rapidly moves up in the vertical direction by the hydraulic pressure of the launching device 6. The impact body 1 is fixed to the tip of the shaft 6a so that the impact body 1 can be impacted and separated from the impact transmission table lower surface 2f by hydraulic pressure.

The operation of the present embodiment thus configured will be described in relation to the vibration sensor mounting mechanism 20. In FIG. 3, during the impact test, the integration of the vibration transmitting table 7 and the impact transmitting table 2 on the fixing bolt shaft 10 is released by contracting the fixing cylinder 9. Therefore, the specimen 3 moves integrally with the shock transmission table 2.

Next, when performing a vibration test, the fixed cylinder 9 is extended and the connection ring 13 is pushed down, and the vibration table 7 and the shock transmission table 2 are integrated by the fixed bolt shaft 10. As a result, the test specimen 3 is
Through the vibration table 7.
Then, a vibration test can be performed by applying a three-dimensional low-frequency vibration component to the vibration table 7 using the vertical vibration device 12 and the horizontal vibration device 11.

Next, referring to FIGS. 1 and 2, the piston shaft 2 of the air cylinder 24 of the vibration sensor mounting mechanism 20 will be described.
When the 41 is lowered, the fixing plate 26 of each vibration sensor 16 is
The upper surface is separated from the lower surface of the vibration table 7 by a predetermined gap. At this time, since the piston shaft 241 is formed of a hexagonal rod, the rotation is restricted in a plane perpendicular to the sensor separation / contact direction. Can be. Also, the piston shaft 241
A guide plate 29 made of a rubber plate is interposed between the square-shaped sensor mounting plate 25 and the square-shaped sensor mounting plate 25, and the guide plate 29 slides on the side wall 213, thereby moving the air cylinder 24 installed on the shock vibration absorber 22. Plays a stable role.

When the impact body 1 collides, an impact force of 1000 G or more acts on the lower surface of the vibrating table 7. At this time, the upper surface of the fixed plate 26 of each vibration sensor 16 is higher than the lower surface of the vibrating table 7. Are separated by a predetermined gap,
In addition, the casing upper plate 212, the side wall 213, and the bottom plate 211
The impact force transmitted through the casing bottom plate 21
1 and each of the vibration sensors 16 greatly differ from the resonance frequency of the impact force (specifically, the shock wave is 7 to 1).
Although it is 0 KHz, there is an intervening one having a resonance frequency of about 10 Hz, which is much lower than this.) It is also possible to block the impact acceleration from the casing bottom plate 211.

Next, after the impact load is transmitted, the air pressure controlled by the throttle 249 is injected into the air cylinder 24 of the vibration sensor mounting mechanism 20 from the air injection port 247, thereby raising the piston shaft 241 to increase the piston shaft 241. The upper surface of the fixed plate 26 of each vibration sensor 16 is brought into close contact with the lower surface of the vibration table 7. At this time, the coordinate position of the acceleration sensor 16 does not change because the piston shaft 241 is formed of a hexagonal rod and the guide plate 29 is interposed.

Further, when the fixed plate 26 presses the lower surface of the vibration table 7, it compresses the shock-vibration absorber 22 located on the opposite side, but between the cylinder mounting plate 23 and the casing bottom plate 211. Since the bottom stopper 27 is provided, air is injected into the air cylinder 24, and when the piston shaft 241 rises, the top of the bottom stopper 27 that is suspended from the casing bottom plate 211 abuts the cylinder mounting plate 23, and the shock vibration absorber 22 is regulated.

As a result, the upper surface of the fixed plate 26 of each of the vibration sensors 16 is closely fixed to the lower surface of the vibration table 7.
The vertical shaker 12 and the horizontal shaker 11 can accurately detect acceleration such as seismic wave excitation applied to the excitation table 7.

Therefore, according to the present embodiment, the vibration sensor is held apart from the vibration table during the operation of the impact force, so that the vibration sensor is not damaged by the impact force. When transmitting the vibration acceleration due to the excitation force to the specimen, the vibration sensor is tightly fixed to the excitation table surface, so even when the low-frequency vibration test is performed continuously to the impact test, the low-frequency vibration component is The measurement can be performed accurately without damaging the vibration sensor that measures.

[0039]

As described above, according to the first and second aspects of the present invention, during the operation of the impact force due to the collision, the impact force (1) is held apart from the lower surface of the excitation table in the air.
000 G) does not damage the vibration sensor.

According to the third aspect of the present invention, the vibration sensor is not damaged even when an impact force much larger than the measurement range is applied to the preceding stage, and the shock / vibration test apparatus can be used. It is also possible to obtain a vibration sensor mounting mechanism suitably applied to an injection molding machine.

According to the fourth aspect of the present invention, the vibration sensor is always positioned in the direction of the predetermined coordinate axis even when the vibration sensor moves away. Furthermore, according to the invention of claim 5, the stopper means can avoid unnecessary compression of the shock vibration absorber (anti-vibration rubber), and can withstand long-term use.

[Brief description of the drawings]

FIGS. 1 and 2 show a mounting mechanism of a vibration sensor according to an embodiment of the present invention. FIG. 1 (A) is a plan view,
(B) is BB sectional drawing of (A).

FIG. 2 is a sectional view taken along the line AA of FIG.

FIGS. 3 and 4 are configuration diagrams showing an impact / vibration test apparatus according to an embodiment of the present invention, and FIG. 3 is a front view thereof.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical bullet (collision object) 2 Impact transmission table 3 Specimen 6 Launcher 7 Vibration table 16 Vibration sensor 20 Vibration sensor mounting mechanism 21 Casing 22 Impact vibration absorber 23 Cylinder mounting plate 24 Air cylinder 26 Sensor fixing plate 27 Bottom stopper

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuhiro Okano 1200, Higashi-Tanaka, Oji, Komaki-shi, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Nagoya Guidance Propulsion System Works Nagoya Guidance Propulsion System Works

Claims (5)

[Claims] 1. A shock / vibration test method for testing the strength of a test piece by adding an impact force due to a collision and a vibration acceleration due to an exciting force to the test piece, wherein the vibration sensor for measuring the vibration acceleration comprises: An impact / vibration test method characterized in that the impact / vibration test method is held apart from the vibration measurement surface during the action of the impact force, and is fixedly adhered to the vibration measurement surface when transmitting the vibration acceleration by the exciting force to the specimen. 2. An impact / vibration test apparatus for testing the strength of a test piece by adding an impact force due to a collision and a vibration acceleration due to an exciting force to the test piece. A vibration sensor for detecting vibration in a predetermined coordinate axis direction is mounted on a vibration table for transmitting vibration acceleration due to a vibration force to the specimen via a sensor mounting mechanism. The vibration sensor is held apart from the vibration table, and when transmitting the vibration acceleration by the vibration force to the specimen, a separation means is provided so that the vibration sensor is fixed to the vibration table surface. Shock and vibration test equipment. 3. A mounting mechanism for a vibration sensor for performing vibration measurement in a predetermined coordinate axis direction after a large impact force significantly larger than a vibration measurement range is applied in advance, comprising: a casing fixed to a vibration measurement surface; And a vibration sensor attached via an impact vibration absorber and a cylinder means. The mounting height of the vibration sensor is held apart from the vibration measurement surface when the cylinder means is not operating, and the vibration is measured when the cylinder means is operating. A vibration sensor mounting mechanism characterized in that the height is set to be closely fixed to a surface. 4. A connection between the cylinder means and the vibration sensor is made through a sensor swing prevention means, and when the vibration sensor moves away from or closes by the cylinder means, the sensor is positioned in a predetermined coordinate axis direction. The vibration sensor mounting mechanism according to claim 3, wherein the vibration sensor is configured to be detachable. 5. The vibration sensor mounting mechanism according to claim 3, further comprising stopper means for restricting a pressing amount of the impact vibration absorber pressed when the cylinder means operates.