JPH0445097B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration damping characteristic tester for determining the vibration damping characteristics of a vibration damper used in a towed wave receiver.

[Conventional technology]

FIG. 4 is a schematic diagram showing a vibration damper being towed by a ship together with a towed receiver. In the figure, 1 is the towed receiver, and 2 is the towed receiver 1. A vibration damper is attached, 3 is a ship towing the towed receiver 1, 4 is a winch installed on the ship 3, 5 is a towing cable fed out from the winch 4, and the towing cable The vibration damper 2 is attached to the vibration damper 5, and the towed type wave receiver 1 and the towed cable 5 are electrically connected by a signal line 6 disposed inside the vibration damper 2.

As shown in the figure, the towed type receiver 1 is towed into the sea by a ship 3 via a towing cable 5, and receives sound waves in the sea and converts them into electrical signals.
This electrical signal is sent to the ship 3 via the signal line 6 and the towing cable 5.

In such a configuration, vibrations from the ship are transmitted to the towing cable 5 during towing, and
The towing cable 5 itself receives resistance from seawater and generates vibrations.

Therefore, these vibrations are directly transmitted to the towed receiver 1.
In order to prevent vibrations from being transmitted to the towed receiver 1 and to attenuate the vibrations to the extent that the towed receiver 1 is not affected, a vibration damper 2 made of elastic rubber or the like is installed between the towed receiver 1 and the towed receiver. If the performance of the vibration damper 2 is poor, that is, if the vibration damping effect is small, the vibration will be transmitted to the towed receiver 1, and this vibration will become acceleration noise. As a result, the function of the towed receiver 1 will be hindered.

Therefore, conventionally, before using the vibration damper 2, its performance has been tested using a testing machine as shown in FIG.

In FIG. 5, a water tank 7 is filled with water or seawater 8, and a vibration damper 2 is set therein, one end of the vibration damper 2 is connected to a piston 9 for excitation, and the other end is connected to a piston 9 for excitation. is pulled in the direction of arrow B by a weight 15 via a simulated towed receiver 10 and a wire rope 14 routed by rollers 11, 12, and 13. 16 is a hydraulic power source that drives the piston.

In this state, the reciprocating motion of the piston 9 in the A direction applies vibrations to the vibration damper 2 corresponding to the vibrations transmitted from the towing cable 5 to the vibration damper 2 in FIG. The values of accelerometers 17 and 18 that are
The vibration damping characteristics of the vibration damper 2 were measured by comparing the two values.

[Problem that the invention seeks to solve]

However, in the device configured as described above, since the mounting position of the roller is fixed, the work of mounting the weight, that is, the work of pulling the vibration damper, is dangerous and requires a great deal of labor.

In addition, the roller is installed at the edge of the tank, so every time you change the model of the vibration damper or simulated towed receiver,
The length of the wire rope had to be adjusted according to each length, and each time a dangerous tensioning operation had to be performed.

Furthermore, even if resonance occurs in the wire rope, it is difficult to make fine adjustments to the length of the wire rope as described above, so the resonance cannot be completely prevented, and the influence of this resonance makes it impossible to measure the exact value of the vibration damping characteristic. There was a problem.

[Means for solving problems]

The present invention provides a pseudo towed receiver having the same mass as the towed receiver and connected to the rear end of a vibration damper, and a pseudo towed receiver that accommodates these vibration dampers and the simulated towed receiver. A water tank filled with water or seawater so that these are submerged, a vibration applying means that applies vibration from the front end of the vibration damper, and an acceleration that measures the acceleration due to the vibration applied by the vibration damper at both ends of the vibration damper. and a tensioning means for applying tension to the vibration damper via the pseudo towed receiver, the tensioning means including a wire rope, rollers, etc. for applying tension to the vibration damper. The present invention is characterized in that the weight is mounted on one movable pedestal, and the pedestal is pulled by a winch via a moving wire rope.

[Effect]

With the above configuration, the present invention attaches the weight to the wire rope in a state where the tensile force is released, and then moves the frame on which the wire rope, rollers, and weight are mounted by a winch via the moving wire rope. , the wire rope can be gradually tensioned to lift the weight and indirectly tension the vibration damper.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 is a sectional view showing an embodiment of a vibration damping characteristic testing machine according to the present invention, Fig. 2 is a sectional view showing the state of the same embodiment before wire rope tension, and Fig. 3 is a main part of the same embodiment. FIG.

In the figure, 20 is an aquarium, and water or seawater 21 is placed in the aquarium 20.

22 is a vibration damper, which is a pseudo towed receiver 2
3 and is housed in the water tank 20 and submerged in water.

24 and 25 are accelerometers; one accelerometer 24
is the other accelerometer 25 at the front end of the vibration damper 22.
is attached to the rear end of the vibration damper 22. 2
6 is a piston rod that penetrates the side wall of the water tank 20, one end of which is connected to the accelerometer 24, and the other end connected to the piston 29 in the cylinder 28 connected to the hydraulic power source 27, and the connecting member. 30
are connected via.

Reference numeral 31 denotes a pedestal, which is a tensioning means for applying tension to the vibration damper 22 in the apparatus of the present invention.

Rollers 32, 33, and 34 are attached to the pedestal 31, and in particular, the roller 32 is attached to an arm 35 provided below the pedestal 31 so as to be submerged in the water tank 20.

The wire rope 36 is connected to the rollers 32, 33, 3
4, the direction is changed and the weight 37 can be suspended.

Wheels 38 are attached to the lower part of the pedestal 31 so that it can move in the longitudinal direction of the water tank 20.

A moving wire rope 39 is attached to the frame 31, and this moving wire rope 39 can be wound around a winch 40.

With the above configuration, in this embodiment, during the tension work before measurement, first, as shown in FIG. 4, the weight 37 is attached to the wire rope 36 in a state where the tension force is released. By winding up the moving wire rope 39 with the winch 40, the frame 3 is
1 in the direction of arrow C and gradually apply tension to the wire rope 36 to lift the weight 37, thereby applying tension to the vibration damper 22.

In this state, due to the reciprocating movement of the cylinder 29 in the A direction, vibrations corresponding to the vibrations transmitted from the towing cable 5 to the vibration damper 2 in FIG. The vibration damping characteristics of the vibration damper 22 are measured by measuring the values of the set accelerometers 24 and 25 with the measuring device 41 and comparing the two values.

〔Effect of the invention〕

As explained in detail above, the present invention eliminates the danger and labor associated with attaching a weight, that is, tensioning the vibration damper, by applying tension to the vibration damper indirectly via a movable frame. did.

In addition, as mentioned above, the tensioning work becomes easier, so
Even if the length of the vibration damper or simulated towed receiver varies depending on the model, the test can be performed simply by moving the position of the mount by winding the winch.

Furthermore, since the tensile force can be precisely adjusted according to the model to be tested as described above, resonance of the wire rope can be prevented and vibration damping characteristics can be measured more accurately.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the vibration damping characteristic testing machine according to the present invention, FIG. 2 is a cross-sectional view showing the state of the same embodiment before the wire rope is stretched, and FIG.
FIG. 4 is a schematic diagram showing a vibration damper being towed by a ship together with a towed wave receiver, and FIG. 5 is a cross-sectional view showing the prior art. 22... Vibration damper, 20... Water tank, 37...
Weight, 31... Frame, 36... Wire rope,
40...Winch.

Claims (1)

[Claims] 1. A vibration damping characteristic tester for determining the vibration damping characteristics of a vibration damper attached to a towed receiver used underwater, which has the same mass as the towed receiver. and a pseudo towed receiver connected to the rear end of the vibration damper; a water tank containing water or seawater to accommodate the vibration damper and the pseudo towed receiver so that they are submerged; a vibration applying means that applies vibration from the front end of the damper; an accelerometer that measures acceleration due to the vibration applied by the vibration applying means at both ends of the vibration damper; In a vibration damping property testing machine having a tensioning means for applying tension to the vibration damper, as the tensioning means, a wire rope, rollers, and a weight for applying tension to the vibration damper are mounted on one movable pedestal, and the pedestal is A vibration damping property testing machine characterized by being pulled by a winch via a moving wire rope.