JP2000025658A - Liquid sealed rubber mount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid sealed type rubber mount for vibration control which has vibration control ability in intermediate and high frequency ranges, does not induce resonance for impact vibration in a wide frequency range, and reduces rolling. SOLUTION: A liquid sealed chamber 20 is fixed to one end of a case 11 of a mount to accommodate a damper plate 22. It is connected with cushion rubber 28 narrowly grabbing guide-shaft-shaped laminate plates 29 having a bolt 27 connected with the damper plate 22. The cushion rubber 28 is decreased in spring constant with hardness Hs of 45 deg.-60 deg.. High damping liquid of 50,000-150,000 cSt is filled into the liquid sealed chamber 20. Vibration control of vertical vibration is excellent at intermediate and high frequencies because the spring constant is low, resonance is not induced even for impact vibration thanks to high damping liquid, cylindrical laminate shape of the cushion rubber 28 increases horizontal spring constant, and therefore, rolling is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled rubber mount for vibration isolation, and more particularly to a liquid-filled rubber mount for mounting a driver's cab of an industrial vehicle on a vehicle body.

[0002]

2. Description of the Related Art FIG. 1 shows the overall structure of a cab mount of a dump truck. Brackets 3 and 4 fixed to a frame 2 of a dump truck 1 have a floor 6 of a cab 5 via a liquid-filled rubber mount 10. The cab 5 is mounted to prevent the vibration from the road surface or the like from being directly transmitted to the cab 5.

FIG. 2 is a detailed view of a portion A in FIG. 1. A case 11 of a liquid-filled rubber mount 10 is fastened to a bracket 4 by bolts 12 and nuts 13. The guide shaft 14 of the liquid-filled rubber mount 10 has a nut 15
The cab 5 is mounted on the floor 6 by vibration-proof mounting.

As conventional liquid-filled mounts, a liquid-filled mount 50 shown in a side sectional view of FIG. 7 and a viscous mount 60 shown in a side sectional view of FIG. 8 are often used.

[0005] In a liquid-filled mount 50 shown in FIG. 7, a case 51 and a boss 53 having a bolt 52 are connected by a cushion rubber 54. A rubber diaphragm 55 having an orifice 56 therein is attached to the tip of the boss 53, and the periphery of the diaphragm 55 is fixed to the case 51.

The diaphragm 55 is composed of the case 51 and the chamber A 57 and the chamber B 5.
8 and so on. A liquid is sealed in the A chamber 57 and the B chamber 58, and both chambers communicate with each other through an orifice 56.

When a load is applied in the vertical direction, the case 51 and the boss 53 are relatively displaced while deforming the cushion rubber 54. At that time, the liquid passes through the orifice 56 and the chamber A 5
7 moves between the chamber 7 and the B chamber 58, and the vibration is attenuated by the resistance force when the orifice 56 passes.

In a viscous mount 60 shown in FIG. 8, a liquid sealing chamber 62 is fixed to one end of a case 61.
A damper plate 63 having a stopper rubber 64 is housed therein.

A guide shaft 65 having bolts 66 is fastened to the damper plate 63 by bolts 67. The hardness of the guide shaft 65 and the case 61 is Hs7.
It is joined by a cushion rubber 68 of about 0 °.

The liquid filling chamber 62 has a viscosity of 50,000 to 1
A high attenuation liquid of about 00000 cst is sealed, and when a load is applied in the vertical direction, the damper plate 63 agitates the attenuation liquid, and the vibration is attenuated by the damping force generated at that time.

[0011]

The damping characteristics of the liquid-filled mount depend on the orifice diameter and the flow rate through the orifice. FIG. 9 is a graph showing the damping characteristics using the input widening of the liquid-filled mount as a parameter. The horizontal axis represents the frequency, and the vertical axis represents the damping coefficient.

As can be seen from FIG. 9, a large vibration damping effect can be obtained at a specific frequency, but resonance is induced with respect to input vibration in a wide frequency band such as an impact vibration, and vibration occurs. In addition, there is a problem that a lateral damping property cannot be obtained and a roll occurs.

FIG. 10 is a graph showing the loss factor between the liquid-filled mount and the viscous mount, wherein the horizontal axis represents the frequency and the vertical axis represents the loss factor. As is clear from the figure, the loss factor of the viscous mount is larger in a wider frequency band than that of the liquid-filled mount, and does not induce resonance even when shock vibration is applied, but it is necessary for low vibration and low noise. However, there is a problem that attenuation is large even in a high frequency range, and the vibration isolation effect is poor.

As a countermeasure, if the hardness of the mount rubber is reduced and the spring constant is reduced to improve the vibration isolating effect in medium and high frequency regions, the deflection against the load in the lateral direction increases, and rolls occur. There's a problem.

Further, the viscous mount has a problem in that the damping property in the lateral direction is poor structurally and a roll occurs.

FIG. 11 is a side sectional view of the viscous mount 60, and FIG. 12 is a view taken along the line DD of FIG. As shown in the figure, both the liquid filling chamber 62 and the damper plate 63 are circular.

A large damping force can be obtained for the displacement in the vertical direction because the damping force acts on the area of the diameter d of the damper plate 63, but the thickness b of the stopper rubber 64 for the displacement in the horizontal direction. When the damper plate 63 is displaced to the dotted line position as shown in FIG. 12, the liquid moves smoothly from part E to part F along the circumference as shown by the arrow, as shown in FIG. Therefore, almost no damping force can be obtained.

The present invention has been made in view of the above problems, and exhibits an excellent vibration isolation effect in a high frequency range, which is required for low vibration and low noise, and is used when driving on a rough road. It is an object of the present invention to provide a liquid-filled rubber mount that does not resonate even with impact vibration in a wide frequency band and that is less likely to roll.

[0019]

In order to achieve the above object,
The liquid-filled rubber mount according to the present invention is configured such that the independent one member and the other member are connected via a cylindrical mounting rubber, and the damping liquid is fixed to the liquid-filled chamber fixed to the one member. And a damper plate fixed to the other member, wherein the liquid mounting type vibration damping mount includes a cylindrical plate in which the cylindrical mounting rubber is tightly adhered inside to form a laminated shape. At the same time, the cylindrical mounting rubber has a hardness exceeding Hs 45 ° and Hs
60 ° or less, and the attenuation liquid to be sealed in the liquid sealing chamber has a viscosity exceeding 50,000 cst and 150,000 cst.
It is characterized as follows.

[0020]

According to the present invention, the provision of the laminated cylindrical plate inside increases the horizontal spring constant and reduces the roll. In addition, the hardness of the cylindrical mount rubber of the liquid-filled rubber mount is Hs45ｓ60.
゜, the spring constant in the vertical direction is small,
Improves vibration isolation in the middle and high frequency ranges. Further, since the viscosity of the damping liquid is set to 50,000 to 150,000 cst, high damping properties are exhibited in a wide frequency band.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a liquid-filled rubber mount according to the present invention will be described below in detail with reference to the drawings. FIG. 3 is a side sectional view of an embodiment of a liquid-filled rubber mount according to the present invention, and FIG. 4 is a plan view as viewed from B in FIG.

At the end of the case 11 of the liquid-filled rubber mount 10, a liquid-filling chamber 20 having a stopper plate 21 is provided.
Is fixed. The liquid sealing chamber 20 has a rubber stopper 2
The damper plate 22 having the holes 3 and the holes 26 is accommodated therein, and a gap 25 is provided between the periphery of the damper plate 22 and the liquid sealing chamber.

The guide shaft 14 having a bolt 27 is fastened to the damper plate 22 by a nut 24. The guide shaft 14 and the case 11 are connected by a cushion rubber 28 to which a cylindrical laminated plate 29 is tightly fitted. The hardness of the cushion rubber 28 is Hs45 ゜
60 °.

The liquid enclosing chamber 20 contains a high-viscosity damping liquid having a viscosity of 50,000 to 150,000 cst, such as a silicon liquid.

When the vehicle starts running, the case 11 and the guide shaft 14 are relatively displaced in the vertical direction (axial direction) due to vibration from the road surface or the like. However, since the hardness of the cushion rubber 28 is reduced, the spring constant in the vertical direction is reduced. Smaller,
Demonstrates anti-vibration properties against vibrations in medium and high frequencies.

As shown in FIG. 4, the cushion rubber 28 is formed into a cylindrical laminated shape by the laminated plate 29.
The horizontal spring constant is increased, which reduces the occurrence of cab rolls.

When the case 11 and the guide shaft 14 are vertically displaced relative to each other, the damper plate 22 stirs the liquid filling chamber 20 up and down, and the stirred high-viscosity damping liquid passes through the gap 25 and the hole 26. Moving. The cushion rubber 28 has a small displacement in the lateral direction due to the laminated plate 29, and the damper plate 22 is set to have a narrow gap 25 within a range where the damper plate 22 does not interfere with the liquid filling chamber 20. I do.

Therefore, a higher damping force than the conventional viscous mount is exerted in a wide frequency band, and resonance is not induced even in an input vibration in a wide frequency band such as an impact vibration.

FIGS. 5 and 6 are graphs showing the effect. FIG. 5 shows the vertical vibration transmissivity, the vertical axis shows the vertical vibration transmissivity, and the horizontal axis shows the frequency. In the graph, the thick solid line indicates the liquid-filled rubber mount of the present invention, and the thin solid line indicates the conventional viscous mount.

FIG. 6 shows the horizontal vibration transmissibility, the vertical axis shows the horizontal vibration transmissivity, and the horizontal axis shows the frequency. In the graph,
The thick solid line indicates the liquid-filled rubber mount of the present invention, and the thin solid line indicates the conventional viscous mount.

In each case, as compared with the conventional viscous mount, the vibration transmissibility of the liquid-filled rubber mount of the present invention is reduced over all frequencies, indicating the effect of vibration damping and reduction of roll.

[0032]

As described above in detail, in the liquid-filled rubber mount according to the present invention, the hardness of the rubber for the cylindrical mount of the liquid-filled rubber mount for the purpose of vibration isolation is Hs4.
The temperature is lowered to 5 ° to 60 °, and a cylindrical plate is tightly fitted inside to form a cylindrical laminated shape.
A high viscosity attenuation liquid of 0 to 150,000 cst was used.

For this reason, the spring constant in the vertical direction is small, and it is excellent in vibration damping of the vibration of the high-frequency liquid, which is necessary for preventing vibration and noise.

In addition, a high damping property is obtained in a wide frequency range, and no resonance is induced even with respect to an input vibration in a wide frequency band such as an impact vibration.

Further, since the mounting rubber is laminated, the spring constant in the horizontal direction is increased, and the occurrence of roll can be prevented.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a cab mount of a dump truck.

FIG. 2 is a detailed view of a portion A in FIG. 1 and is a detailed view of mounting of a mount.

FIG. 3 is a side sectional view of an embodiment of the liquid-filled rubber mount of the present invention.

FIG. 4 is a plan view of an embodiment of the liquid-filled rubber mount of the present invention.

FIG. 5 is a graph of a vertical vibration transmission rate of a rubber mount according to an example.

FIG. 6 is a graph of the horizontal vibration transmissibility of the rubber mount of the example.

FIG. 7 is a side sectional view of a conventional liquid filled mount.

FIG. 8 is a side sectional view of a conventional viscous mount.

FIG. 9 is an attenuation characteristic curve of a conventional liquid-filled mount.

FIG. 10 is a loss factor curve between a conventional liquid-filled mount and a viscous mount.

FIG. 11 is a side sectional view of a conventional viscous mount.

FIG. 12 is a bottom sectional view of a conventional viscous mount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Dump truck 2 ... Frame 3, 4 ... Bracket 5 ... Cab 6 ... Floor 10 ... Liquid-filled rubber mount 11 ... Case 12, 15, 27 ... Bolt 13, 24 ... Nut 14 ... Guide shaft 21 ... Stopper plate 22 ... Damper Plate 23 ... Rubber stopper 25 ... Gap 26 ... Hole 28 ... Cushion rubber 29 ... Laminated plate

Claims (1)

[Claims] 1. An independent one member and the other member are connected via a cylindrical mounting rubber, and a damping liquid and the other member are provided in a liquid sealing chamber fixed to the one member. In a liquid-filled anti-vibration mount including a damper plate fixed to a member, the cylindrical mounting rubber includes a cylindrical plate tightly adhered inside to form a laminated shape, and The mounting rubber of
A liquid-filled rubber mount having a hardness of more than Hs45 ° and not more than Hs60 °, and a damping liquid filled in the liquid filling chamber having a viscosity of more than 50,000 cst and not more than 150,000 cst.