JPH08136392A - Excitation shaft coupling structure of vibration test machine - Google Patents

Abstract

PURPOSE: To make possible accurate excitation without torsion and vibration in simple constitution by coupling an excitation shaft to a vibrating base through a bearing part coupling part providing a static pressure bearing and holding the excitation shaft by a hydraulic guide composed of the static pressure bearing. CONSTITUTION: An oil flow passage 2d and an oil discharge opening (pocket 2c ) are provided in a T-shaped bearing part 2b of one end of an excitation shaft 2, and a bearing part coupling part 4 is constituted by a press arm 4a fixed on the side face of the bearing part 2b and a vibrating base 1 and a removable press arm 4b . The coupling part 4 forms a static pressure bearing due to oil pressure between the pocket 2c , the inner face of the arm piece 4b and the side face of the vibrating base 1, and the excitation shaft 2 is coupled to a specified position of the vibrating base 1 with a gap of tens μm. In addition, a hydraulic guide fixed on the floor is mounted to the intermediate of the shaft 2, holds the shaft 2 by the static pressure bearing with the gap of tens μm due to oil pressure. The movement in only the direction of the shaft center of the shaft 2 is guided by the hydraulic guide 5. Thereby even at high band frequency, vibration without any strain is applied to the vibrating base 1 in simple constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating shaft mounting structure for an electrodynamic vibration tester.

[0002]

2. Description of the Related Art Recently, vibration experiments have become very important for evaluating the seismic resistance and safety of large structures such as nuclear power generation facilities. There is a demand for a multi-degree-of-freedom vibration testing machine capable of vibrating in various degrees of freedom.

On the other hand, since these test products are large,
In many cases, it is tested with a scale model, and when conducting a seismic test with a scale model, it is necessary to apply vibration at a frequency that is higher than the vibration frequency of the actual earthquake in proportion to the scale ratio. For example, the upper limit frequency of an earthquake is about 10 Hz, but if the scale ratio is 1/20, it is 200
It is necessary to add vibration up to about Hz, and
It is necessary to excite electronic parts up to about 2000Hz,
There is a demand for a vibration tester capable of exciting up to a frequency in such a high range, and therefore a strong connection between an electrodynamic vibration generator and a vibration table driven by the electrodynamic vibration generator, and A vibrating shaft connection structure that accurately transmits vibration without distortion is required.

Conventionally, as a vibrating shaft connecting structure of a vibrating table of a multi-degree-of-freedom vibration testing machine, there is, for example, Japanese Patent Publication No. 49-7171 (hereinafter referred to as a first conventional example), which is shown in FIGS. 6 and 7. As shown, the side surface of the vibrating table 104 in the X and Y directions and Z
Is connected to an electric vibration generator in the X and Y directions via hydrostatic bearings 302, 303, 304, and further through a connection rod 110 in the Z direction. And an electric vibration generator are connected to each other, and as shown in the figure, it has a guide frame 114 and a guide frame guide means so that the vibration in one direction does not affect the vibration in the other direction. A connecting portion between the vibrating table 104 and the vibrating means is indicated by reference numeral 100, and description of other reference numerals is omitted.

As another example, Japanese Patent Publication No. 54-44461 (hereinafter referred to as a second conventional example) shown in FIGS. 8 and 9
In the drawings, the vibrating table 501 is supported by a vibrating table guiding device 502 with a static pressure bearing so that it can vibrate only in one plane and is vibrated in each direction of multiple degrees of freedom. In (1), a plurality of synchronously connected vibration hydraulic cylinders 503, 503 are allowed to move in a direction perpendicular to the vibration direction of these vibration hydraulic cylinders, and a vibration force in the vibration direction is applied. The vibrating table 50 by the couplers 506, 506 having hydrostatic bearings for transmitting
It is configured such that vibration can be obtained by connecting to the corresponding portion of 1. The same applies to the Y direction, but details are omitted. Although not shown, the same applies to the Z direction.

Further, as another example, there is the invention described in Japanese Patent Publication No. 3-81093 (hereinafter referred to as the third conventional example) filed by the present applicant. The configuration is the same as that of the present invention, and the description and illustration thereof are omitted.

[0007]

In the first conventional example, since the guide frame and the guide frame guide means are required as described above, there is a drawback that the overall structure of the multi-degree-of-freedom vibration testing machine becomes complicated and large. there were.

In the second conventional example, since the structure of the coupler is a U-shaped fork bracket, the vibration system is increased by one due to the coupler, and not only the frequency characteristic drops in the high range, but also in the axial direction. Since the guide is also used as the vibration cylinder, there are drawbacks that the size and other restrictions can be restricted and the structure is not very robust.

Therefore, an object of the present invention is to solve the conventional drawbacks and to propose a vibration shaft connecting structure of a multi-degree-of-freedom vibration testing machine which is most suitable for vibration testing of a test object having a simplified overall structure. is there.

[0010]

In order to solve the above-mentioned problems, in Claim 1, an electrodynamic vibration generator and a vibration table driven by the electrodynamic vibration generator are connected by a vibrating shaft. In the connection structure described above, a static pressure bearing is provided at one end of the vibrating shaft to connect to a predetermined portion of the vibrating base, and a bearing part coupling part is provided at an intermediate side part of the vibrating shaft. A vibrating shaft connecting structure having a hydraulic guide including a static pressure bearing and a mounting structure in which a vibrating table of the electrodynamic vibration generator is fixed to the other end of the vibrating shaft is configured.

Further, according to a second aspect of the present invention, a rectangular parallelepiped bearing portion is provided at one end of the cylindrical vibration shaft and is extended to both sides at a right angle to the axial direction and is formed in a T shape together with the vibration shaft. A pressing arm provided so as to project from the side surface of the vibrating table at predetermined upper and lower right and left portions near the bearing portion, and tip portions of the upper and lower pressing arms for gripping the bearing portion so as to wrap the side surface of the vibrating table and the pressing arm. The vibrating shaft coupling structure according to claim 1, wherein the vibrating shaft connecting structure is formed of left and right pressing arm pieces connected to each other, and a static pressure bearing is provided on a side surface of the vibrating table facing the bearing portion and a facing surface of the pressing arm piece.

[0012]

As described above, the present invention is configured as in the first and second aspects of the invention, and the electrodynamic vibration generator capable of vibrating up to a high frequency of about 200 to 2000 Hz is vibrated. Since it is connected to a predetermined position of the vibration table by the vibration axis of the shaft connection structure, it has a simple structure and has excellent frequency characteristics, and there is no torsional vibration in the vibration table due to the hydraulic guide that guides in the axial direction. Accurate vibration can be realized.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view of the embodiment of the present invention with a part omitted, FIG. 2 is a cross-sectional explanatory diagram of a part of the present invention, and FIG. 3 is a perspective view with an omission of part of the present invention.

In each figure, 1 is a rectangular parallelepiped vibrating table on which an object to be tested or the like is mounted, 1a is a connecting portion, 2 is a vibrating shaft,
2a is a shaft portion, 2b is a bearing portion, 2c is a pocket, 2d is an oil flow path, 3 is an electrodynamic vibration generator, 3a is a drive coil, 3
b is a yoke, 3c is an exciting coil, 3d is a vibration table,
Reference numeral 4 is a bearing connecting portion, 4a is a holding arm, 4b is a holding arm piece, 5 is a hydraulic guide, 5a is a pocket, 6 is an oil tank, 7 is a pump, and 8 is a motor. In addition, the yoke 3
b is indicated by a broken line.

The vibrating shaft 2 has a T-shape having a cylindrical shaft portion 2a and a bearing portion 2b provided at one end of the shaft portion 2a and extending on both sides at right angles. 1 of 1
The pressing arm 4a fixed to the side surface and the removable pressing arm piece 4b form the bearing portion connecting portion 4.

That is, as shown in FIGS. 2 and 3, the bearing portion 2
An oil passage 2d is formed through b, and a discharge port of the passage 2d, that is, a pocket 2c is provided in a pocket 2c recessed on the entire surface and the rear surface of the bearing portion 2b to hold the bearing portion 2b and a holding arm 4a. It is sandwiched between the holding arm piece 4b and the pocket 2c and the inner surface of the holding arm piece 4a and the side surface of the vibrating table 1 are opposed to each other with a gap of several tens of μ to form a mounting portion. Here, the front surface side of the bearing portion 2b is
The outlet of the oil passage 2d and the pocket 2c may not be provided and may be directly opposed to the side surface of the vibrating table 1.

By applying a high pressure oil pressure to the pocket 2c by the oil pressure source formed by the oil tank 6, the pump 7 and the motor 8 together with the piping shown by the broken line in FIG.
As shown by the arrow in FIG. 2, the vibrating shaft 2 is provided with sufficient rigidity in the axial direction to transmit vibration in the axial direction.

On the other hand, the shaft portion 2a having the bearing portion 2b and the pressing arm 4a are sufficiently spaced from each other in the direction perpendicular to the axial direction, and when hydraulic pressure is applied, they are perpendicular to each other. It is set to be free.

The hydraulic guide 5 is mounted in the middle of the vibrating shaft 2, is fixed to a floor surface (not shown), and is a hydrostatic bearing by the hydraulic pressure from the hydraulic source appropriately arranged on the floor surface. Holds the vibrating shaft 2 with a gap of several tens of μ
The vibrating shaft 2 is guided so that it can be moved only in the axial direction.

As shown in FIG. 2, the end portion 2a of the vibrating shaft 2 opposite to the bearing portion 2b is a vibrating table 3d of the electrodynamic vibration generator.
The drive coil 3a is mounted on the end of the vibration table 3d. The drive coil 3a is shown in FIG. 2 by a broken line to show an example. Has been inserted.

The yoke 3b is fixed to a floor surface (not shown), has an exciting coil 3c therein, and a direct current is passed through the exciting coil 3c by means (not shown) to pass a direct magnetic field across the drive coil 3a. Is generated and an alternating current is caused to flow through the drive coil 3a by a means (not shown) to vibrate the vibration table 3d.

FIGS. 4 and 5 show one embodiment of the present invention, X and Y.
FIG. 4 is a plan view and FIG. 5 is a side view. 1 is a vibrating table, 2 is a vibration axis,
3 is an electrodynamic vibration generator, 3d is a vibration table, 4 is a bearing connecting portion, and 5 is a hydraulic guide. As shown in the figure, the vibration shaft 2 is connected to a predetermined portion of the vibrating table 1 by the bearing portion connecting portion 4 at one end of the vibration shaft 2, and the center of the vibration shaft 2 is supported by the hydraulic guide 5 for vibration. The other end of the shaft 2 is fixed to the vibration table 3d of the electrodynamic vibration generator 3. With the above configuration,
Since the bearing connecting portion 4 and the hydraulic guide 5 are provided with hydrostatic bearings (not shown), the multi-degree-of-freedom vibration testing machine is
And is excited in the Y direction.

[0023]

As described in detail above, the present invention provides
In a mounting structure of a vibrating shaft in which an electrodynamic vibration generator and a vibrating table driven by the electrodynamic vibration generator are connected by a vibrating shaft, a static pressure bearing is provided at a connecting portion with the vibrating table. Is formed, and one end of the excitation shaft is connected through the bearing connection portion, and the other end of the excitation shaft is fixed to the excitation table of the electrodynamic vibration generator. And a vibrating means connected to the vibrating means, and a hydraulic guide consisting of a hydrostatic bearing is provided in the middle of the vibrating axis to constitute a vibrating axis mounting structure of an electrodynamic vibration generator.
And a T-shaped bearing portion formed as a bearing portion connecting portion at one end of a columnar shaft portion to provide a hydrostatic bearing, and a vibrating shaft mounting structure according to claim 1. So 20
With the electrodynamic vibration generator capable of exciting up to a high frequency vibration of about 00 Hz and the mounting structure of the vibration shaft connected to a predetermined position of the vibrating table, the conventional drawback is solved, and at the high frequency range, In addition, the frequency characteristics are superior, and the hydraulic guide that independently guides in the axial direction enables strong guides, and has an effect that vibration can be obtained without distortion on the vibrating table with a simple configuration.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a partial sectional explanatory view of the present invention.

FIG. 3 is a partially omitted perspective explanatory view of the present invention.

FIG. 4 is a plan view of an application example of the present invention.

FIG. 5 is a side view of an application example of the present invention.

FIG. 6 is a side view of a first conventional example.

FIG. 7 is an enlarged explanatory view of a first conventional example.

FIG. 8 is a plan view of a second conventional example.

FIG. 9 is a side view of a second conventional example.

[Explanation of symbols]

 1 Shaking table 1a Connection part 2 Excitation shaft 2a Shaft part 2b Bearing part 2c Pocket 2d Oil flow path 3 Electrodynamic vibration generator 3a Drive coil 3b Yoke 3c Excitation coil 3d Excitation table 4 Bearing part connection part 4a Holding arm 4b Presser arm piece 5 Hydraulic guide 5a Pocket 6 Oil tank 7 Pump 8 Motor 100 Connection between vibration table and vibrating means 104 Vibration table 110 Connection rod 114 Guide frame 301 Rod 302 Hydraulic bearing 303 Hydraulic bearing 304 Hydraulic bearing 305 Hydraulic pump 306 Direction 307 Direction 308 Hydraulic bearing 309 Hydraulic bearing 501 Shaking table 502 Shaking table guiding device 503 Pressurizing hydraulic cylinder 503a Piston rod 504 Base 505 Pressurizing hydraulic cylinder 505a Piston rod 506 Coupler 506a Fork 5 6b bracket 507 connector 507a fork 507b bracket

Claims (2)

[Claims] 1. A connection structure in which an electrodynamic vibration generator and a vibrating table driven by the electrodynamic vibration generator are connected by a vibrating shaft, and a static pressure is applied to one end of the vibrating shaft. A bearing portion connecting portion provided with a bearing so as to be connected to a predetermined portion of the vibrating table, a hydraulic guide including a static pressure bearing provided on an intermediate side portion of the vibrating shaft, and the other end of the vibrating shaft. A vibrating shaft coupling structure having a mounting structure configured by fixing a vibrating table of the electrodynamic vibration generator. 2. A rectangular parallelepiped bearing which is provided at one end of a cylindrical vibrating shaft and extends horizontally to both sides at a right angle to the axial direction of the vibrating shaft and is formed in a T-shape together with the vibrating shaft. Portion, a holding arm provided at a predetermined upper and lower right and left portions near the bearing portion so as to project from the side surface of the vibrating table, and tip portions of the upper and lower holding arm for gripping the bearing portion so as to be wrapped with the side surface of the vibrating table and the holding arm. 2. The vibrating shaft connecting structure according to claim 1, further comprising: left and right holding arm pieces connected to each other, and having a static pressure bearing on a side surface of the vibrating table facing the bearing portion and a facing surface of the holding arm piece.