JP3562543B2 - Liquid-filled mount - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a liquid-filled mount used as a cabin mount that supports a cabin in a vibration-proof manner in an agricultural machine, a construction machine, an automobile, or the like.
[0002]
[Prior art]
As shown in FIG. 3, a known liquid-filled mount of this type reduces the vibration (also referred to as low-frequency vibration or shock) of the cabin itself by increasing the attenuation around the resonance frequency (5 to 10 Hz) of the cabin. Attenuated. However, in this liquid-filled mount, the dynamic spring constant is high in the idle rotation range of the engine, so that the vibration of the engine is easily transmitted to the cabin. In particular, agricultural machines such as tractors do not have an engine mount, and the vibration of the engine is transmitted directly to the body. Therefore, by providing a cabin mount effective against the vibration of the engine, the vibration transmitted to the cabin in the idle rotation range (idle Isolation of vibrations is also an important factor.
[0003]
[Problems to be solved by the invention]
In view of the above points, the present invention can achieve both "high damping" for low frequency vibration and "low dynamic spring" in an idle rotation range, and thus can exhibit excellent vibration isolation performance. The purpose is to provide a mount.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, a liquid-filled mount according to the present invention includes an elastic member made of a rubber-like elastic material and a diaphragm, wherein one of the attaching portions provided with a sleeve and the other attaching portion disposed on the outer peripheral side of the sleeve are provided. And an airtight space is provided by connecting the airtight space, the airtight space is partitioned by a partition into a first liquid chamber on the elastic body side and a second liquid chamber on the diaphragm side, and the partition is fixed inside the other mounting part. Then, the sleeve is inserted into the inner peripheral side of the partition so as to be relatively displaceable, a shock orifice for communicating the two chambers with the partition is provided, and a sub-diaphragm is provided in the partition and one surface thereof is the first liquid chamber. And the other surface is provided so as to face the second liquid chamber, and the partition portion is provided with a cylindrical portion protruding into the second liquid chamber, and the outer peripheral side of the sleeve is provided on the inner peripheral side of the cylindrical portion. Second place to be placed Secure the over blanking the idle orifice provided between the second sleeve and the tubular portion, and to encapsulate the working fluid in the two chambers.
[0005]
[Action]
When idle vibration is input to the liquid-filled mount of the present invention having the above configuration, the internal pressure of the first liquid chamber changes, and this change in the internal pressure is transmitted to the second liquid chamber via the sub-diaphragm, When a part of the hydraulic fluid passes through the idle orifice in the two-fluid chamber, the change in the internal pressure is canceled. At this time, since the liquid column resonance occurs in the idle orifice and the dynamic spring constant is reduced, the idle vibration is effectively insulated. The frequency of the idle vibration is around 25 to 35 Hz.
[0006]
When low-frequency vibration is input to the liquid-filled mount of the present invention having the above-described configuration, the internal pressure of the first liquid chamber changes greatly, and a part of the hydraulic fluid in the first liquid chamber changes due to the change of the internal pressure. By passing through the shock orifice, this change in internal pressure is canceled. At this time, since the liquid column resonance occurs in the shock orifice and the dynamic spring constant is reduced, the low frequency vibration is effectively attenuated. The frequency of the low frequency vibration is around 5 to 10 Hz.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The liquid-filled mount according to the present invention having the above-described configuration includes three rubber-like elastic members of an elastic member, a diaphragm, and a sub-diaphragm. Therefore, the main parts or all parts of the mount are sorted into three groups centered on these three rubber-like elastic bodies, and one vulcanized molded product is formed for each group, and the three vulcanized molded products are formed. It is preferable to configure the mount by combining the above. The shock orifice and the idle orifice are set to have different expansion elastic moduli based on their respective functions.
[0008]
【Example】
Next, embodiments of the present invention will be described with reference to the drawings.
[0009]
As shown in FIG. 1, one mounting portion 1 having a sleeve 2 and an annular plate 3 and the other mounting portion 4 having an annular first case 5 and an annular case 6 have an annular rubber shape. An annular airtight space 9 is provided inside the mount by being connected via an elastic body (also referred to as a main body rubber portion or rubber leg portion) 7 and a diaphragm 8 made of an elastic material, and the airtight space 9 is partitioned. A first liquid chamber (also referred to as a main liquid chamber) 11 on the elastic body 7 side (upper side) and a second liquid chamber (also referred to as a sub liquid chamber) on the diaphragm 8 side (lower side) by a portion (also referred to as a partition member) 10. It is divided into 12.
[0010]
The partition part 10 is made of an annular orifice case 13 fixed inside the other mounting part 4 (the inner peripheral side of the second case 6), and a rubber-like elastic material having an annular shape on the inner peripheral side of the orifice case 13. And a ring-shaped sub-diaphragm case 15 connected via a connecting body 14 of the above-mentioned. The sleeve 2 is disposed in an inner peripheral hole 15a of the sub-diaphragm case 15 so as to be displaceable in its axial direction (vertical direction). I have. Here, "displaceably disposed" means that a very small gap (not shown) is provided between the sub-diaphragm case 15 and the sleeve 2 and a downward vibration input is received from above. , The sleeve 2 slides with respect to the sub-diaphragm case 15, and the sleeve 2 is relatively displaced downward, and returns to the original position after this displacement.
[0011]
The orifice case 13 is provided with a shock orifice 16 for communicating the first liquid chamber 11 with the second liquid chamber 12. The sub-diaphragm case 15 integrally includes an outer cylindrical portion 15b, a flat annular portion 15c, and an inner cylindrical portion 15d. The sub-diaphragm case 15 has a substantially U-shaped cross section with the two cylindrical portions 15b and 15d directed downward. The sleeve 2 is formed on the inner peripheral side of the inner peripheral cylindrical portion 15d so as to be displaceable as described above. A through hole 15e is provided at one position on the circumference of the radial portion 15c, and a sub-diaphragm 17 made of a rubber-like elastic material is provided so as to close the through hole 15e. Therefore, one surface of the sub-diaphragm 17 faces the first liquid chamber 11 and the other surface faces the second liquid chamber 12. The sub-diaphragm 17 is formed in a dome shape bulging toward the first liquid chamber 11.
[0012]
A second sleeve 18 is fitted on the outer peripheral side near the lower end of the sleeve 2, and the upper end of the second sleeve 18 is arranged between the outer cylindrical portion 15 b and the inner cylindrical portion 15 d of the sub-diaphragm case 15. In particular, an annular idle orifice 19 is provided between the outer cylindrical portion 15d and the second sleeve 18 and is disposed on the inner circumferential side of the outer cylindrical portion 15b. The second sleeve 18 is provided with a tapered portion 18a extending upward so that the second sleeve 18 fitted on the outer peripheral side of the sleeve 2 is disposed between the outer peripheral cylindrical portion 15b and the inner peripheral cylindrical portion 15d. Have been. A working liquid (also referred to as a sealing liquid) 20 such as a viscous fluid is sealed in the liquid chambers 11 and 12.
[0013]
The liquid-filled mount having the above configuration is molded as the following three vulcanized molded products.
[0014]
First vulcanized molded product ...
The elastic body 7 is vulcanized and bonded to the sleeve 2, the plate 3 and the first case 5 to form a first vulcanized molded product.
Second vulcanized molded product
The diaphragm 8 is vulcanized and bonded to the second case 6 and the second sleeve 18 to form a second vulcanized molded product.
Third vulcanized molded product ...
The sub-diaphragm 17 and the connecting body 14 integrally formed therewith are vulcanized and bonded to the sub-diaphragm case 15 and the orifice member 13 to form a third vulcanized molded product.
[0015]
Next, the operation of the liquid-filled mount having the above configuration will be described as follows. The mount is mounted on the cabin side of the agricultural machine with one mounting portion 1 and mounted on the body side with the other mounting portion 4 to support the cabin with vibration isolation.
[0016]
That is, first, when an idle vibration of about 25 to 35 Hz is input to the mount from above, the internal pressure of the first liquid chamber 11 changes, and this change in the internal pressure is transmitted to the second liquid chamber 12 via the sub-diaphragm 17. The change in the internal pressure is canceled by transmitting the part of the hydraulic fluid 20 in the second fluid chamber 12 through the idle orifice 19. At this time, since the liquid column resonance occurs in the idle orifice 19 and the dynamic spring constant is lowered as shown in FIG. 2, this idle vibration can be effectively insulated.
[0017]
Also, when low frequency vibration of about 5 to 10 Hz is applied to the mount from above, the internal pressure of the first liquid chamber 11 changes greatly, and the change in the internal pressure causes a part of the hydraulic fluid 20 in the first liquid chamber 11 to change. Passes through the shock orifice 16, so that this change in internal pressure is canceled. Further, at this time, liquid column resonance occurs in the shock orifice 16 and the dynamic spring constant is reduced as shown in FIG. 2, so that this low frequency vibration can be effectively attenuated.
[0018]
Therefore, as is evident from the above operation, both "high damping" against low frequency vibration and "low dynamic spring" in the idle rotation range are satisfied, and in this sense, liquid filling that exhibits excellent vibration isolation performance. An expression mount can be provided. Moreover, since it is manufactured by combining three vulcanized molded products as described above, it has a feature that it is easily manufactured while having a complicated structure.
[0019]
【The invention's effect】
The present invention has the following effects.
[0020]
That is, when idle vibration having a predetermined frequency is input to the liquid-filled mount of the present invention having the above configuration, the internal pressure of the first liquid chamber changes, and the change in the internal pressure is changed via the sub-diaphragm. The change in the internal pressure is canceled by transmitting the hydraulic fluid to the second fluid chamber and passing a part of the hydraulic fluid through the idle orifice in the second fluid chamber. At this time, since the liquid column resonance occurs in the idle orifice and the dynamic spring constant is reduced, the idle vibration can be effectively insulated. Further, when low-frequency vibration having a predetermined frequency is input to the liquid-filled mount of the present invention, the internal pressure of the first liquid chamber changes greatly, and the change in the internal pressure causes a part of the hydraulic fluid in the first liquid chamber to change. This change in internal pressure is canceled by passing through the shock orifice. At this time, since the liquid column resonance occurs in the shock orifice and the dynamic spring constant is reduced, this low frequency vibration can be effectively attenuated. Accordingly, both “high damping” against low-frequency vibration and “low dynamic spring” in the idle rotation range are satisfied, so that it is possible to provide a liquid-filled mount exhibiting excellent vibration isolation performance.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a liquid-filled mount according to an embodiment of the present invention. FIG. 2 is a graph showing a change in a spring constant depending on the frequency of the mount. FIG. Graph showing the change in spring constant depending on the frequency of the mount.
DESCRIPTION OF SYMBOLS 1 One mounting part 2 Sleeve 3 Plate 4 The other mounting part 5 First case 6 Second case 7 Elastic body 8 Diaphragm 9 Airtight space 10 Partition part 11 First liquid chamber 12 Second liquid chamber 13 Orifice case 14 Connector 15 Sub-diaphragm case 15a Inner peripheral hole 15b Outer peripheral cylindrical part (tube part)
15c Radial portion 15d Inner peripheral cylindrical portion 15e Through hole 16 Shock orifice 17 Sub-diaphragm 18 Second sleeve 18a Tapered portion 19 Idle orifice 20 Hydraulic fluid

Claims (1)

The one attachment portion (1) having the sleeve (2) and the other attachment portion (4) disposed on the outer peripheral side of the sleeve (2) are connected to the elastic body (7) made of a rubber-like elastic material and the diaphragm ( 8), an airtight space (9) is provided, and the airtight space (9) is separated from the first liquid chamber (11) on the elastic body (7) side and the diaphragm (8) side by a partition (10). The partition (10) is partitioned into a second liquid chamber (12), the partition (10) is fixed inside the other mounting part (4), and the sleeve (2) is positioned on the inner peripheral side of the partition (10). The partition (10) is provided with a shock orifice (16) that is displaceably inserted and communicates the two chambers (11) and (12) with the partition (10), and a sub-diaphragm (17) is provided on the partition (10). The other surface faces the second liquid chamber (12) while facing the first liquid chamber (11). The partition (10) is provided with a cylindrical portion (15b) protruding from the second liquid chamber (12), and is disposed on the outer peripheral side of the sleeve (2) on the inner peripheral side of the cylindrical portion (15b). The second sleeve (18) is fixed and an idle orifice (19) is provided between the cylindrical portion (15b) and the second sleeve (18). A liquid-encapsulated mount, characterized by enclosing (20).

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