JPH1030974A - Excitation equipment of peripheral jet air-cushion-type - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent vibration environmental pollution from being generated in an excitation apparatus for a vibration table in an up-and-down-direction vibration testing machine or the like by a configuration wherein a vibration with a low-frequency and large amplitude can be generated by utilizing a cushion pressure as an excitation force and the vibration table is not connected directly to the ground. SOLUTION: A vibration table 1 is installed inside a cushion chamber 8 at a pit 10, and a pressure air tank 2 is attached to the lower part of the vibration table 1. The high-pressure air is supplied to the pressure air tank 2 from a high-pressure-air producing apparatus 4, and the air is jetted into the cushion chamber 8 from air jet nozzles (air nozzles) 3 attached to the whole face on the outer circumference of the vibration table via opening and shutting valves 5. The air nozzles 3 can change their directions by operating motors 7 by a nozzle-direction change device 6. When angles of the jet nozzles (the air nozzles) 3 are changed, the vibration table 1 which is levitated in a space is moved up and down by a change in a jet force, and the vibration table is excited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for vibrating a vibration table in a vertical vibration tester or the like.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a conventional electric or hydraulic vibration excitation equipment. In the figure, 01 is a vibration generator,
02 is an actuator of the vibration generator 01, 03 is a vibrating table that is vibrated by the actuator 02, 04 is a support table supporting the vibrating table 03, 05 is an auxiliary table, 06 is a test table for mounting a DUT, and 07 is a test table. It is a test product.

When the actuator 02 is driven by electric or hydraulic pressure to apply vibration to the vibration table 03, a test table 06 attached to the vibration table 03 via an auxiliary table 05 is vibrated.

[0004] A test article 07 is fixed to a test table 06, and a vibration test is performed.

Although FIG. 3 shows an example in which the vibration is applied in the horizontal direction, the vibration can be applied in the vertical direction in principle.

[0006]

By the way, in the above-mentioned conventional electric or hydraulic vibration excitation equipment,
Especially in a vertical vibration tester, 100
There is a problem that it is difficult to increase the size beyond tonf.

[0007] In addition, although the hydraulic type can be enlarged, there is a problem that the larger the auxiliary equipment such as a hydraulic motor and a hydraulic pump becomes, the larger the equipment becomes, and the equipment cost becomes enormous.

Further, in the conventional vibration equipment, the vibration table is directly connected to the ground.
A problem that causes environmental problems on vibration occurs.

An object of the present invention is to provide a new vibration equipment which has solved the above-mentioned disadvantages.

[0010]

According to a first aspect of the present invention, there is provided a peripheral jet-type air cushion type vibration equipment provided with a vibration table provided in an air cushion chamber provided in a pit. It is characterized by comprising an air nozzle which is attached downward to the entire outer periphery of the lower portion of the shaking table and is configured to be tiltable at an angle, a device for changing the direction of the air nozzle, and a device for supplying compressed air to the air nozzle.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 is a configuration diagram of a peripheral jet air cushion type vibration equipment, and FIG.
(A), (b), (c) is an operation explanatory view of the present invention.

In FIG. 1, reference numeral 1 denotes a vibration table provided in a cushion room 8 of a pit 10, and a pressurized air tank 2 is mounted below the vibration table 1.

High-pressure air is supplied to the pressurized air tank 2 from a separately provided high-pressure air producing device 4.

Reference numeral 3 denotes an air jet nozzle (air nozzle) mounted on the entire outer periphery of the lower portion of the vibrating table 1. The nozzle 3 is supplied with pressurized air from a pressurized air tank 2 via an on-off valve 5. Have been.

Although not shown, the on-off valve 5 is configured to be opened and closed by remote control.

Reference numeral 6 denotes a separately provided nozzle direction changing device which changes the direction of the ejection nozzle (air nozzle) 3 by operating the motor 7.

The shaking table 1 is located in the pit 10,
The air blown out from the air nozzle 3 goes out through a ventilation hole 11 opened at the lower side of the pit 10.

The jet nozzle (air nozzle) 3 is arranged on the entire surface around the lower part of the vibrating table 1, and the pressure air jetted from the nozzle forms a curtain jet u as shown in FIG. The cushion pressure Pc generated in the chamber 8 is maintained.

By changing the angle α of the ejection nozzle (air nozzle) 3 by the nozzle direction changing device 6, the vibration test of the object mounted by raising and lowering the vibration table 1 can be performed.

Next, the operation of the present invention will be described in detail with reference to FIG.

When the pressure air is ejected from the nozzle 3 while cyclically changing the direction of the air nozzle 3 disposed on the entire surface around the lower part of the shaking table 1, as shown in FIG. The vibrating table 1 floating in the space in the cushion chamber 8 moves up and down due to the fluctuation of the ejection power.

The following is an example of such an experiment. Nozzle tilt angle α
When the jet flowing out of the air nozzle 3 forms a curtain jet u as shown in FIG. 2 (a), there is a gap between the cushion pressure Pc and the flying height h of the shaking table as shown in FIG. 2 (b). Have a relationship.

In FIG. 2B, when the nozzle inclination angle α is reduced, the cushion pressure Pc increases.

In FIG. 2B, Pc is a cushion pressure,
Po is the atmospheric pressure, and α is the nozzle inclination angle.

Now, as shown in FIG. 2C, the nozzle angle α ₁
The vibration table with cushion pressure Pc ₁ when it is balanced at a height h _1.

From this state, the nozzle inclination angle is changed from α ₁ to α ₂
If it is changed to, the cushion pressure temporarily increases from Pc ₁ to Pc ₂ , but the levitation height of the shaking table increases from h ₁ to h _{2 in the} process of gradually returning to the equilibrium point of Pc ₁ .

Next, when the nozzle inclination angle α is returned to α ₁ in this state, the cushion pressure falls from Pc ₁ to Pc _D, and in the process of returning to the equilibrium point, the flying height returns from h ₂ to h ₁ .

If the above cycle is repeated, a pressure fluctuation occurs in the cushion chamber, and the vibrating table can be excited by the force.

[0029]

As described above, the peripheral jet-type air cushion type vibration equipment of the present invention has the following effects.

(1) Since the cushion pressure is used as the exciting force, a large vibration with a low frequency amplitude can be generated.

(2) Since the shaking table is not directly connected to the ground, even if the size is increased, no environmental problem is caused due to vibration around.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an air cushion type vibration equipment according to an example of an embodiment of the present invention.

FIGS. 2A and 2B are explanatory diagrams of the operation of the present invention, in which FIG. 2A is an operation diagram at a lower portion of a shaking table, FIG. 2B is a diagram showing a relationship between a cushion pressure Pc and a flying height h of the shaking table, and FIG. FIG. 10 is a diagram showing a change in the floating height of the shaking table according to the change of.

FIG. 3 is a configuration diagram of an example of a conventional vibration device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration table 2 Pressure air tank 3 Jet nozzle (air nozzle) 4 High pressure air production device 5 On-off valve 6 Nozzle direction changing device 7 Motor 8 Cushion room 10 Pit 11

Claims (1)

[Claims] 1. A vibrating table installed in an air cushion chamber provided in a pit, an air nozzle mounted downward on the entire outer periphery of a lower part of the vibrating table and configured to be tiltable at an angle, and changes the direction of the air nozzle. A peripheral jet type air cushion type vibration equipment, comprising: a device; and a device for supplying pressurized air to the air nozzle.