JP2855735B2 - Body bending vibration prevention device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing a vehicle body bending vibration of a railway vehicle.

2. Description of the Related Art Forces applied to a vehicle body of a railway vehicle are roughly classified into a static load due to a loaded load and a dynamic load applied to the vehicle body during traveling. The load direction is generally divided into up and down, left and right, and front and back.

Of the dynamic loads, the vertical load is mainly the vertical inertia force during running.When a railway vehicle travels at high speed on a track that has gone bad due to long-term train running, the body becomes Excited.

This excitation frequency causes primary bending vibration of the vehicle body. The bending vibration of the vehicle body is particularly likely to occur in a vehicle body in which an extruded aluminum material, which has recently been reduced in weight, is integrally welded.

A dynamic vibration absorber is known as a method of damping the vehicle body bending vibration. Conventional dynamic vibration absorbers suspend weights or underfloor equipment on the lower surface of the floor with springs.

FIG. 7A shows a vibration model of the dynamic vibration absorber. Mass M
The dynamic vibration absorber attached to the controlled object of the one-degree-of-freedom system having a spring constant K and a spring constant K is composed of three elements: an auxiliary mass (md), a vibration absorber spring (kd), and a damper (Cd). It serves as a feedback compensation element as represented by the block diagram in FIG.

Problems to be Solved by the Invention In the conventional dynamic vibration absorber, as described above, a weight or an underfloor device is supported by being suspended by a spring that works in a pulling direction. It is difficult to provide vibration performance. Further, if the spring is broken, the entire device may be damaged.

The present invention provides a vehicle body bending vibration prevention device which has excellent vibration damping performance against vehicle body bending vibration and can support a weight or a floor device even when a spring is broken, in order to overcome the above current situation. Things.

Means for Solving the Problems In order to achieve the above object, a vehicle body bending vibration prevention apparatus according to the present invention includes a support member projecting under the floor of a vehicle body, a spring in a compression direction of a vibration-proof rubber having a vertical spring property. Through force, supporting weights or underfloor equipment.

The anti-vibration rubber is configured to support a weight or an underfloor device by using a spring force in a compression direction of the anti-vibration rubber having a spring constant synchronized with the vehicle body primary bending natural frequency.

Then, the attachment of the weight or the underfloor equipment to the support member is performed from the center under the floor of the vehicle body to both sides in the longitudinal direction of the vehicle body,
Each one-quarter length range of the vehicle body is set as the mounting range, and a plurality of weights or underfloor equipment having a total mass in the range of 3 to 15% of the vehicle body mass are arranged and tuned to the vehicle body primary bending natural frequency. Attach via the vibration constant rubber with spring constant.

The vibration preventing device according to the present invention supports a weight or an underfloor device through a spring force in a compression direction of a vibrating rubber having a spring property in a vertical direction as a method of using the vibration isolating rubber.
That is, as shown in FIG. 1A and FIG. 2A, an anti-vibration rubber (3) having a spring property in a vertical direction placed on a horizontal portion formed on a support member (2) is interposed, and A weight or underfloor equipment (4) is placed and supported. Therefore,
When the primary bending vibration of the vehicle body occurs, the weight or the underfloor device (4) supported via the vibration isolating rubber acts as a dynamic vibration absorber, and the weight or the underfloor device (4) is moved in the opposite direction to the displacement due to the bending vibration of the vehicle body. By displacing, a force in the direction opposite to the vehicle body bending direction is generated, and the vehicle body bending vibration can be reduced.

Further, when the vibration isolating rubber is damaged, the weight or the underfloor equipment is directly supported by the supporting member to which the vibration isolating rubber is attached, so that it can be prevented from falling off.

The attachment of the weight or the underfloor equipment is performed as shown in FIG. 4b by the total mass of a plurality of weights or the underfloor equipment 機器 m = m ₁
+ M ₂ + m ₃ +... Is in the range of 3 to 15% of the vehicle body mass M, and as shown in FIG. the range attaching a length range of 1 / 4L, anti-vibration having a spring property the spring constant is tuned to the vehicle primary flexural natural frequency fM shown in expression 1 below _{k 1, k 2, k 3} , in the vertical direction of the ...... The weight or the underfloor equipment is provided to support the weight or the underfloor equipment by utilizing the spring force in the compression direction of rubber. With this attachment, excellent vibration damping performance can be exhibited.

The reason why the total mass Σm of the weights or the underfloor equipment is set to 3 to 15% of the mass M of the vehicle body is based on the results of various experiments (see FIG. 5 of the embodiment) in a range where the weight increase of the entire vehicle does not become large. To work most effectively.

Also, the mounting range should be within 1 / 4L of the length of the vehicle body from the center under the floor of the vehicle body to both sides in the longitudinal direction of the vehicle body, respectively, because from the actual measurement of the bending vibration mode of the vehicle body, the vertical bending displacement in this range is large. This is because it is effective to install in this range.

EXAMPLES Example 1 As shown in FIGS. 1a and 1b, the inverted L is placed under the floor of the vehicle body (1).
Four support members (2) each consisting of an arm rod of a mold are arranged in a square position. Then, an anti-vibration rubber (3) having a spring property in the vertical direction is attached to the upper side of the end of the horizontal portion of the support member (2).
The weight or underfloor equipment (4) is supported via a spring force in the compression direction of the vibration-proof rubber (3).

As described above, the dynamic vibration absorber constituted by the weight or the underfloor equipment (4) is, for example, as shown in FIG.
Three dynamic vibration absorbers (5) are provided below the floor in the longitudinal center and on both sides from the longitudinal center such that the centers are located at 1 m each.

In the above configuration, the test was carried out under the conditions of a body weight of 14000 kg and a total weight of 1449 kg (483 kg × 3, 10.4% of the body weight). When the spring constant k of the anti-vibration rubber is obtained from the above equation, k = 483 kg × (12.3 × 2π) ² = 2.88 × 10 ⁶ N / m at the vehicle body primary bending natural frequency fM = 12.3 Hz. It is tuned to the primary bending natural frequency fM.

Then, the vehicle body floor center vertical vibration acceleration, riding comfort and round analysis were tested. The results are shown in FIGS. 6a and 6b show the results obtained for the case without the dynamic vibration absorber for comparison.

As a result, the vehicle body floor center vertical vibration acceleration is significantly reduced at each vehicle speed in both the vibration acceleration and the round analysis when the present invention is implemented, compared to the case without the dynamic vibration absorber, and the vibration damping effect is large. You can see that.

Example 2 In the dynamic vibration absorber shown in FIGS. 2a and 2b, the supporting member (2) is formed under the floor of the vehicle body (1) with the support plate (2) forming a long plate into a U-shaped cross section, with its release surface facing upward. Anti-vibration rubber at the four corners (3)
The weight or the underfloor equipment (4) is provided with a vibration isolator (3)
In support.

Advantageous Effects of Invention According to the present invention, a dynamic vibration absorber is constructed by supporting a weight or an underfloor device under the floor of a vehicle body through a spring force in a compression direction of a vibration-isolating rubber having a spring property in a vertical direction. The braking performance can be obtained, and the bending vibration of the vehicle body can be significantly reduced. Further, when the vibration isolating rubber is damaged, the weight or the underfloor equipment is supported by the support member and does not fall off.

[Brief description of the drawings]

FIG. 1 is a front view (a) and a plan view (b) of a dynamic vibration absorber according to one embodiment of the present invention, and FIG. 2 is a front view (a) of a dynamic vibration absorber according to another embodiment of the present invention. ) And plan view (b)
FIG. 3 is an explanatory view showing the mounting position of the dynamic vibration absorber of the first embodiment, FIG. 4 is an explanatory view showing the mounting of the dynamic vibration absorber according to the present invention, FIG. Fig. 5 shows a test result of a railway vehicle equipped with a vehicle body bending vibration prevention device according to an embodiment of the present invention. FIG. 5B is a graph showing the relationship between the vehicle speed and the vibration frequency, and FIG. 6 is a result of a comparative test performed on a railway vehicle without the vehicle body bending vibration prevention device.
Is a graph showing the relationship between the vibration frequency and the vehicle body floor center vertical vibration acceleration, FIG. 6B is a graph showing the relationship between the vehicle speed and the vibration frequency, FIG. 7A is an explanatory diagram showing a model of the dynamic vibration absorber, FIG. 7b is a block diagram of the vibration suppression model. DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Support member 3 ... Anti-vibration rubber 4, ... Weight, Underfloor equipment M ... Body weight, K ... Constant md ... Auxiliary mass, kd ... Vibration absorber spring Cd ... damper

Claims (1)

(57) [Claims] 1. A vehicle body bending vibration preventing device which supports a weight or an underfloor device on a supporting member projecting below the floor of a vehicle body through a compressive spring force of a vibration isolating rubber having a spring property in a vertical direction. A plurality of weights or underfloor devices having a total length of 3 to 15% of the vehicle body, with a 1/4 length range of the vehicle body as a mounting range from the center under the floor of the vehicle body to both sides in the longitudinal direction of the vehicle body, A bending vibration preventing device for a vehicle body supported via a vibration isolating rubber having a spring constant tuned to the vehicle body primary bending natural frequency.