JP2003194219A - Flexible airtight member and vibration resistant device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible airtight member capable of reducing natural frequency and a vibration resistant device improved in vibration resistant performance. <P>SOLUTION: As a reinforcing material of rubber for the flexible airtight member (bellows), knitted stretchable material is used instead of foundation cloth (fabric). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a flexible airtight member such as a bellows or a diaphragm, and a vibration isolator using the flexible airtight member.

[0002]

2. Description of the Related Art The applicant of the present invention has developed a vibration damping device as a device using a bellows. This vibration isolation device basically forms a pressure chamber between a fixed base and a vibration isolation movable base via a flexible airtight member (bellows), and controls the pressure in this pressure chamber to cause vibration. Has the effect of preventing the propagation of. In this vibration isolation device, it is required to reduce the natural frequency of the bellows itself in order to enhance the vibration isolation performance. In the conventional bellows, it is usual to combine a rubber material and a base cloth as a reinforcing material to increase the mechanical strength, but it has been difficult to reduce the natural frequency.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a flexible airtight member capable of lowering the natural frequency and a vibration isolation device having improved vibration isolation performance based on the above awareness of the problems.

[0004]

SUMMARY OF THE INVENTION The present invention concludes that the reason why it is difficult to reduce the natural frequency of a conventional flexible airtight member is that a base cloth is used as a reinforcing material that is bonded to a rubber material. It has been reached. The conventional reinforcing material is made of a woven fabric as is apparent from what is called a base fabric, and the woven fabric has almost no stretchability. The present invention has been made to find that a flexible airtight member having a low natural frequency can be obtained by using a knitted fabric having high elasticity as a reinforcing material instead of the conventional base fabric, that is, woven fabric. Knitting is more elastic than woven fabric, and by combining it with a rubber material, a flexible airtight member (having a low natural frequency) can be obtained.

That is, the flexible airtight member according to the present invention is
A flexible airtight member formed by combining a rubber material and a reinforcing material is characterized in that the reinforcing material is made of knitting.

The present invention further includes a fixed base; and a vibration isolation movable base supported on the fixed base via a pressure chamber formed via a flexible airtight member; In a mode of the vibration isolator in which the member is formed by combining a rubber material and a reinforcing material, the reinforcing material of the flexible airtight member is formed by knitting.

The flexible airtight member may be either a bellows or a diaphragm, but when applied to a bellows, the knitted material is tubular (shape like a sliced stocking) in a free state before being bonded to a rubber material. It is better to use.

[0008]

1 to 4 show an embodiment in which the present invention is applied to a bellows 10. The bellows 10 has a substantially semi-circular shape offset from the axis X by a distance Y, and has a rotationally symmetrical shape rotated about the central axis X. The base 11 made of a rubber material and the rubber base 11 And a reinforcing material (base knitted material) 12 made of knitted material bonded to the entire surface of the. The bellows 10 has a central opening 10a above and below the central portion, and a thick annular bead portion 11a formed on the inner peripheral edge of the rubber base 11 is located at the edge portion of the upper and lower central openings 10a. There is. The rubber base 11 and the knitted fabric reinforcing material 12 are bonded to each other generally in such a manner that the knitted fabric reinforcing material 12 is brought into contact with the surface of the rubber substrate 11 during main vulcanization.
The knitting reinforcing material 12 may be embedded in the inside of the No. 1 or the knitting reinforcing material 12 may be provided along the inner surface of the rubber substrate 11.

The base cloth (woven fabric) which is combined with the rubber material of the conventional flexible airtight member is defined as a product made by interlacing warp yarns and weft yarns in two directions, while a knitting reinforcing material. The knitting that composes 12 is defined as a knitting loop that is formed by using only one of the warp yarn and the weft yarn and is intertwined with each other. Knitting is more elastic than woven. The material of the yarns constituting the knitting is known to be wool, hemp, cotton, nylon, acrylic, a mixed yarn of these, and the thickness thereof can be selected depending on the size of the count. The present invention utilizes the excellent elasticity of the knitted fabric, and the material and thickness of the yarns constituting the knitted reinforcement material 12 can be appropriately determined according to the purpose of use and specifications.
However, it is necessary to select a material that is not cut by the heat during the main vulcanization of the rubber substrate 11. Also known as knitting methods are horizontal knits and warp knits, which can be selectively used. 3 and 4 show an example of the horizontal knitting (rubber knitting).

FIG. 5 and FIG. 6 are schematic views of a mold for the main vulcanization of the bellows 10. The preform 11P of the rubber substrate 11 is set on the central mold 21, and the outer periphery of the preform 11P is covered with the cylindrical knitting reinforcing material 12 and brought into close contact therewith. Since the knitting reinforcing material 12 is highly stretchable, it can be easily attached to the outer periphery of the preform 11P. The split dies 22 and 23 are adhered to the upper and lower sides of the center die 21, and these dies are heated to a predetermined temperature and held at that temperature, whereby the preform 11
P is fully vulcanized, and the knitting reinforcing material 12 is bonded to the surface of the P along the surface. Rubber base 11 (preform 11P)
The specific material of is not a matter of the present invention, and known materials can be selected and used according to the purpose of use.

FIGS. 7 and 8 show an example of the structure of a vibration isolation device using the bellows 10 described above. This vibration isolation device includes a fixed base 31 fixed to the ground or a fixed structure, and a vibration isolation movable base 32 on which an object to be isolated from vibration is placed. Between the fixed base 31 and the vibration isolation movable base 32. 4 composed of bellows 10
One pressure chamber 33 is formed. Each pressure chamber 33 includes a bellows 10 and upper and lower central openings 10 of the bellows 10.
The retainer plate 34 is fixed to the fixed base 31, and the retainer plate 35 is fixed to the vibration isolation movable base 32. The retainer plates 34 and 35 are respectively provided on the fixed base 3
The annular bead portion 11a of the rubber base 11 is sandwiched and held between the vibration isolation table 1 and the vibration isolation movable table 32.

The above vibration isolator can eliminate the vibration transmitted to the vibration isolation movable table 32 by controlling the pressure in the pressure chamber 33 according to the vibration applied to the fixed table 31 side.
The bellows 10, which is a combination of the rubber base 11 and the knitting reinforcement material 12, has a low natural frequency, and thus can improve the vibration isolation performance.

In the above embodiments, the single-stage bellows having a semi-circular cross-section has one step. However, the present invention is also applicable to a multi-stage bellows having a plurality of semi-circular cross-sections stacked or a diaphragm. Is.

[0014]

According to the present invention, a flexible airtight member capable of reducing a natural frequency and a vibration isolation device having improved vibration isolation performance are obtained by knitting a reinforcing member which is bonded to a rubber material. Obtainable.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment in which the present invention is applied to a bellows.

FIG. 2 is a perspective view of the same.

FIG. 3 is a schematic view showing an example of knitting.

FIG. 4 is a view on arrow IV in FIG.

5 is a cross-sectional view of the bellows of FIG. 1 in a state in which a mold is opened during main vulcanization.

FIG. 6 is a sectional view of the mold with the mold closed.

FIG. 7 is a plan view of a vibration isolator using a bellows according to the present invention.

8 is a cross-sectional view taken along the line VIII-VIII of FIG.

[Explanation of symbols]

10 Bellows 10a central opening 11 Rubber base 11P preform 11a annular bead portion 12 Knitting reinforcement material 21 center type 22 23 Split type 31 fixed base 32 Vibration isolation movable table 33 Pressure chamber 34 35 Retainer plate

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F16F 15/04 F16F 15/04 A (72) Inventor Keiji Tamaki 1-840 Mitsuhashi Saitama City Saitama Prefecture Gokura Fujikura Industrial Co., Ltd. Omiya Plant (72) Inventor Tomomasa Fujita 1-840 Mitsuhashi, Saitama Prefecture Fujikura Gomu Industrial Co., Ltd. Omiya Plant (72) Inventor Hiroshi Jinda 1-840 Mitsuhashi, Saitama City Fujikura Gomb Industrial Co., Ltd. Company Omiya Factory (72) Inventor Akihiro Hayashi 1-840 Mitsuhashi Saitama City, Saitama Prefecture Fujikura Gomu Kogyo Co., Ltd. Omiya Factory F Term (reference) 3J045 AA06 BA01 BA02 CB11 DA01 EA10 3J048 AA02 AD02 BE02 EA07 3J069 AA22 AA24 DD39 4L002 AA01 AA03 AA06 AA08 BA01 DA03 EA06 FA06

Claims (4)

[Claims] 1. A flexible airtight member obtained by combining a rubber material and a reinforcing material, wherein the reinforcing material is knitted. 2. The flexible hermetic member according to claim 1, wherein the flexible hermetic member is a bellows, and the knitted fabric is tubular in a free state before being bonded to a rubber material. 3. A fixed base; and a vibration isolation movable base supported on the fixed base via a pressure chamber formed via a flexible airtight member, wherein the flexible airtight member is made of rubber. A vibration isolator in which a material and a reinforcing material are joined together, wherein the reinforcing material of the flexible airtight member is made of a knitted fabric. 4. The vibration isolation device according to claim 3, wherein the flexible airtight member is a bellows, and the knitted fabric is a flexible airtight member that is tubular in a free state before being bonded to a rubber material. Vibration isolation device.