JPS6182034A - Fluid-sealed mount for series 4-cylinder engine - Google Patents

Abstract

PURPOSE:To obtain the function for satisfying the shake movement and the secondary vibration of an engine by setting the wall rigidity ratio determined from the static spring constant in the state where an orifice is opened and the static spring constant in the state where the orifice is sealed into a prescribed range. CONSTITUTION:The cylinder part 3 of the base member 1 of a fixed case 2 and an inverted-cone-shaped installation member 7 are joined through a shear- type thick elastic rubber member 9, and the inside fluid chambers 11 and 12 are formed into the upper and lower divisions by an orifice plate 4. When the wall-rigidity ratio of an elastic rubber member 9 which is determined by the static spring constant in the state where the orifice 5 of the orifice plate 4 is opened and the static spring constant in the state where the orifice 5 is sealed is set to 0.5<=a<=1, the high damping for the shake movement of an engine and the low movement factor for the secondary vibration can be achieved at a same time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fluid-filled mount for an in-line four-cylinder engine.

(Prior Art) A typical fluid-filled mount used as an engine mount connects a base member fixed to a frame and a mounting member connected to an engine using a shear type thick elastic rubber material.

A thin rubber-filled diaphragm is fixed to a base member to form a fluid chamber therein, and an orifice plate is provided to divide the fluid chamber into upper and lower sections.

(Problems to be Solved by the Invention) When the mount supports a typical in-line four-cylinder engine for automobiles, the performance requirement for the mount is damping.

In other words, when the peak value of the loss coefficient [tan δ1 is 0.2 or more, the dynamic multiplier expressed by dividing the absolute dynamic spring constant IK'I by the static spring constant [1gl] is the frequency 1 of J [IK'l /Ksl
The value near 00Hz is 2 or less. In other words, if the mount deviates from this range, the damping, which is a major advantage of a fluid-filled mount, becomes too small, and the engine vibration transmitted to the vehicle body becomes too large, resulting in a decline in mount performance.

The purpose of the present invention is to satisfy the above-mentioned performance requirements, that is, simultaneously achieve high damping against engine shaking motion and low dynamic multiplier against secondary vibration, and furthermore, based on setting conditions that are theoretically supported. To provide a fluid-filled mount for a four-cylinder engine.

(Means for Solving the Problems) Therefore, the present invention provides elasticity expressed by the following formula, where the static spring constant in the open state of the orifice is [Ksl, and the static spring constant in the closed state is [Kil]. Wall assembly property of member (3) [al is 0.5
The present invention is characterized in that a fluid-filled mount for an in-line, 4-cylinder engine is configured by setting a in the range of ≦a≦1.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

Figure 1 is a central vertical cross-sectional view of the fluid-filled mount.

The cylindrical part (3) of the pace member (1), which has the cylindrical part (3) upright on the fixed case (2), and the inverted truncated conical mounting member (7) are connected by shearing thick elastic rubber material ( 8), an orifice plate part (0) having an orifice (5) in the center is formed on the inner periphery of the lower part of the cylinder part (3), and a thin rubber diaphragm is attached to the lower surface of this orifice plate part (4). (6)
is bulged into the case (2) and attached thereto, thus defining a main fluid chamber (11) and a sub-fluid chamber (!2) above and below the orifice plate portion (4).

Such a fluid-tight mount fixes the case (2) of the base member (1) on the frame of the vehicle, and the mounting member (7)
Connect the in-line 4-cylinder engine to the mounting bolt (8) protruding from the top.

In the above fluid-filled mount, the loss coefficient [tanδ
1 and the dynamic magnification [IK''l/Ksl and para) - the experimental results that investigated the correlation between the rotation rate and the rotation rate revealed the following.

At a frequency of 100 Hz, 1 to 17 Ksl is approximately a+1.

Here, [al is a parameter called the wall rigidity ratio of the elastic rubber material (8), and the orifice (5)
This value is defined when the static spring constant in the open state is [Ks] and the static spring constant in the closed state is [KjJ]. Note that [δ1] is the phase difference between the displacement applied to the mount and the transmitted force.

The above experimental results are theoretically supported as follows.

First, the fluid-filled mount is represented by a simple model as shown in Fig. 2. In Fig. be.

When calculating this model, one frequency [ω1] get.

If this is graphed, it will look like FIGS. 3 and 4.

From this, [the peak value of tan δ1 and at ω→■
The relationship between [lK”l / Ksl is, m
It can be graphed as shown in Figure 5.

On the other hand, if the above-mentioned performance requirements required for a fluid-filled mount for an in-line four-cylinder engine, that is, tan δ ≧ 0.2 1 and l7 Kg ≦ 2 are drawn in FIG. 5, the area is the range shown by diagonal lines.

Frequency 100Hz teno [lKml/Kg] is almost al1
The performance requirement regarding the spin-ake motion is pa·a ≧ 0.5, and the performance requirement regarding the secondary vibration is al1 ≦ 2 ·′, aS;1.

Therefore, the performance requirements for shake and secondary vibration are simultaneously satisfied [the value range of aJ is 0.5≦a≦1].

As described above, in a fluid-filled mount for an in-line four-gas engine, unless the wall stiffness ratio [al] is within the above range, the engine mount will not satisfy the mechanical shock and the secondary vibration at the same time.

(Effects of the Invention) As described above, according to the present invention, the wall stiffness ratio [al] is set to 0.
Since the fluid-filled mount is configured with the setting within the range of 5≦a≦1, it satisfies the performance requirements for a mount for an in-line 4-cylinder engine, and the above-mentioned theoretically supported setting conditions provide resistance to engine shaking motion. High damping and low dynamic magnification against secondary vibration can be achieved at the same time.

[Brief explanation of drawings]

Figure 1 is a central vertical cross-sectional view of the fluid-filled mount, Figure 2 is a diagram of the model, Figure 3 is a frequency-dynamic spring constant characteristic diagram, Figure 4 is a frequency-loss coefficient characteristic diagram, and Figure 5 is a diagram of the frequency-dynamic spring constant characteristic. is a loss coefficient value-dynamic magnification characteristic diagram. In one drawing, (1) is the base member, (0 is the orifice plate, (5) is the orifice, (6) is the diaphragm, (7)
is a mounting member, (9) is an elastic member, and (11). (12) is a fluid chamber. May 17, 1985, Japanese Patent Application No. 59-189869 2, Name of the invention: Fluid-filled mount for in-line 4-cylinder engine 3, Person making the amendment 4, Detailed description of the invention in the attorney's specification 3nδ 7, Amendment The description of contents is amended as follows. ■, Page 2, line 14, correct the statement [...0.2 or more, absolute] to "...0.2 or more, absolute". 2. On page 5, lines 15 and 16, “The first nophis (
5)" is replaced with "mass flow rate of fluid at 1st no. 5)"
) is corrected as "attenuation coefficient of".

Claims (1)

[Claims] A base member fixed to a frame and a mounting member connected to an in-line 4-cylinder engine are connected by an elastic member to form a fluid chamber inside, and the fluid chamber is divided into two chambers. In a fluid-filled mount equipped with an orifice plate, the static spring constant when the orifice is open is [Ks], and the static spring constant when the orifice is closed is [Ks'], and the following formula a = (Ks' )/(Ks)-1, the wall stiffness ratio [a] of the mount is 0.5≦a
A fluid-filled mount for an in-line four-cylinder engine, characterized in that the fluid-filled mount is configured in a range of ≦1.