JP2004245360A - Annular sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an annular sealing device capable of letting a seal member adhere closely to a circular outer peripheral face of a barlike seal object over its whole periphery to seal satisfactorily, corresponding to various different diameter sizes of the seal object, and sealing satisfactorily even if there are recessed and projecting parts on the outer peripheral face. <P>SOLUTION: This annular sealing device 10 is composed of the seal members 12-1, 12-2 provided with an annular seal part 26, an annular main body 14, an annular sealed pressure chamber 28, and a supply hole 30. The seal members 12-1, 12-2 are overlapped so as to form at least two layers in the radial direction in a condition in which annular seal parts 26 having elasticity are not bonded. They are swelled in the direction of inside diameter by introducing pressure into the pressure chamber 28 so that they adhere closely to the substantially circular outer peripheral face of the seal object over the whole periphery for sealing. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an annular sealing device that seals a substantially circular outer peripheral surface of a sealing object such as a round bar by closely contacting a sealing member.
[0002]
Problems to be solved by the prior art and the invention
For example, an O-ring is conventionally used to seal a sealing object having a circular or substantially circular (hereinafter, simply referred to as substantially circular) outer peripheral surface such as a round bar over the entire circumference. .
However, in a sealing device using such an O-ring, it is necessary to use an O-ring having a different size for each different diameter of the object to be sealed, and it is necessary to prepare another sealing device for each size of the object to be sealed. Was high.
[0003]
Further, in the sealing device using the O-ring, there is a problem that it is difficult to seal well if the outer peripheral surface of the sealing target has irregularities.
However, at present, there is no seal device that can satisfactorily solve such a problem.
[0004]
By the way, it is not intended to provide such a seal, but a clamp device for gripping and clamping an outer peripheral surface of a work such as a round bar is disclosed in Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, etc. It has been disclosed.
[0005]
FIG. 7A shows a clamping device disclosed in Patent Document 2. In the drawing, reference numeral 200 denotes a cylindrical sealing member made of an elastic material, and an axial end 202 is formed of the sealing member 200. It is held by a rigid annular main body 204 having a cylindrical shape and arranged on the outer peripheral side.
[0006]
In the clamp device 206, when pressurized air is supplied from the supply hole 208, the elastically deformable portion 210 has an inner diameter due to the pressure of the pressure chamber 212 formed between the annularly elastically deformable portion 210 and the annular body 204 of the seal member 200. The swells in the direction to reduce the diameter, and the bar-shaped work 214 is gripped and clamped.
The ones disclosed in the following Patent Documents 2 to 4 are basically the same as those shown in FIG.
[0007]
At first glance, the clamp device 206 seals the outer peripheral surface of the work 214 by bringing the annular elastic deformation portion 210 expanded and reduced in the inner diameter direction into close contact with the outer peripheral surface of the work 214, The same clamping device 206 can also be used, and the unevenness of the outer peripheral surface of the work 214 can be absorbed by the elastic deformation of the annular elastic deformation portion 210, so that the sealing can be performed despite the unevenness. appear.
[0008]
However, the clamp device 206 is designed only for the purpose of gripping and clamping the work 214, and it is actually difficult to seal the outer peripheral surface of the work 214 well.
The reason is as follows.
[0009]
Since the expansion / reduction in the radial direction of the annular elastic deforming portion 210 is a deformation in the direction of shortening the circumferential length of the inner peripheral surface, the elastic deforming portion 210 uniformly bulges to the inner diameter side over the entire circumference. The elastic deformation part 210 cannot be reduced in diameter and causes wrinkles to occur in various parts in the circumferential direction, or a certain part in the circumferential direction is irregularly and partially greatly expanded, so that the elastic deformation part 210 has a good circular shape. Can not be held, and therefore cannot be in close contact with the outer peripheral surface of the work (object to be sealed) 214 over the entire circumference, which causes leakage.
The uneven expansion / diameter deformation of the elastic deformation portion 210 in the clamp device 206 also has an adverse effect on the clamping of the work 214.
[0010]
Therefore, in the clamp device 216 shown in FIG. 7B proposed in Patent Document 5 below, the elastic deformation part 210 is divided into three parts in the circumferential direction, and each elastic deformation part 210a is expanded toward the inner diameter side so that the work 214 is formed. I try to hold it.
[0011]
With the clamp device 216, the work 214 can be more stably clamped.
However, in the case of the clamp device 216 shown in FIG. 7B, a sealing function for the workpiece 214, that is, the outer peripheral surface to be sealed, cannot be expected at all.
[0012]
[Patent Document 1]
JP-A-6-47693 [Patent Document 2]
JP-A-6-190767 [Patent Document 3]
JP-A-6-190768 [Patent Document 4]
JP-A-6-339888 [Patent Document 5]
JP-A-8-229868
[Means for Solving the Problems]
The annular sealing device of the present invention has been devised to solve such a problem.
According to the first aspect of the present invention, (a) a sealing member having an annular sealing portion which is elastic and has a thin annular shape, and which expands and contracts in a radial direction over the entire circumference by the action of pressure; (B) a rigid annular main body which is arranged on the outer peripheral side of the seal member and holds the seal member in a state of restricting the annular seal portion from deforming in the outer diameter direction; and (c) the annular seal portion and the annular main body. And (d) a supply hole for supplying a pressurized fluid to the pressure chamber, and the seal member has at least two layers in the radial direction. As described above, the respective annular seal portions are superposed in a non-adhered state, and by introducing pressure into the pressure chamber, the annular seal portions bulge in the inner diameter direction to form a substantially circular outer peripheral surface to be sealed. Make sure that it is tightly sealed and sealed all around. And butterflies.
[0014]
A second aspect of the present invention is characterized in that, in the first aspect, the cross-sectional shape of the annular seal portion has a shape bulging in an arc shape toward the inner diameter side.
[0015]
A third aspect of the present invention is characterized in that, in any one of the first and second aspects, at least two annular seal portions of the seal member, which form at least two layers, are superimposed on each other in close contact with each other.
[0016]
According to a fourth aspect, in the third aspect, the plurality of seal members have substantially the same size and the same shape before overlapping.
[0017]
According to a fifth aspect of the present invention, in the first aspect, the annular sealing device is configured to clamp the sealing target on the outer peripheral surface by expanding and reducing the inner diameter of the annular seal portion. It is characterized in that it also serves as a device.
[0018]
[Action and effect of the invention]
As described above, according to the present invention, the seal members are overlapped so as to form at least two layers in the radial direction in a state where the annular seal portion is not adhered, and the seal members are radially overlapped by introducing pressure into the pressure chamber. It is designed to be swelled and deformed to come into close contact with the substantially circular outer peripheral surface to be sealed.
[0019]
The present inventor has confirmed that the outer peripheral surface of the object to be sealed can be satisfactorily sealed by using such an annular sealing device.
The reason why the sealing can be effectively performed by overlapping the sealing members so as to form at least two layers is considered to be as follows.
[0020]
For example, when the sealing member is composed of only one layer, if the sealing member is expanded and reduced in diameter in the inner diameter direction by the pressure of the pressurizing chamber, wrinkles may be generated in the circumferential direction, or any weak portion in the circumferential direction may be changed. It swells and deforms larger than the part.
[0021]
Thus, once such a partially large bulging deformation occurs, the same part tends to bulge more and more than the other parts, and consequently the sealing member, in particular its annular sealing part Cannot maintain a good circular shape, resulting in a significantly irregular shape having irregularities in the circumferential direction.
With such a shape, the annular seal portion cannot be brought into close contact with the outer peripheral surface of the object to be sealed over the entire circumference, and the sealing cannot be performed satisfactorily.
[0022]
On the other hand, when the seal members are overlapped in at least two layers in the radial direction and the respective annular seal portions are not bonded, there is a circumferential direction of the first-layer annular seal portion on the pressure chamber side (outer diameter side). When the portion is partially swelled and deformed in the inner diameter direction under the action of pressure, the annular seal portion of the second layer on the inner diameter side acts to regulate the partial deformation.
[0023]
At this time, if the first-layer annular seal portion and the second-layer annular seal portion are bonded to each other, the second-layer annular seal portion also partially expands and deforms in the circumferential direction. However, in the present invention, the second-layer annular seal portion is not adhered to the first-layer annular seal portion, and they can move relative to each other to some extent. When the annular seal portion restricts partial deformation of the first-layer annular seal portion, the force or stress generated partially in the second layer increases in the circumferential direction of the second-layer annular seal portion. It is dispersed in the circumferential direction with relative displacement, and it is suppressed that a part of the second layer in the circumferential direction swells greatly.
As a result, the first layer and the second layer can be swelled and reduced in diameter in the inner diameter direction while maintaining a good circular shape. It is considered that they can be in close contact with each other and can be sealed well.
[0024]
In the annular seal device of the present invention, the amount of swelling / diameter deformation of the annular seal portion can be freely controlled by the magnitude of the pressure applied to the annular seal portion. Can be handled by the same annular sealing device.
[0025]
Furthermore, in the annular seal device of the present invention, even if there is some unevenness on the outer peripheral surface of the object to be sealed, the annular seal portion can be brought into close contact with the entire periphery in a satisfactory manner. The outer peripheral surface can be sealed.
[0026]
Here, the annular seal portion may have a cross-sectional shape bulging in an arc shape toward the inner diameter side (claim 2).
In such a case, the sealing function can be further enhanced.
When the cross-sectional shape of the annular seal portion is such an arc-shaped swelling shape, the second-layer annular seal portion may cause partial and irregular swelling deformation of the first-layer annular seal portion. When regulating, the force received by the second layer is easily propagated and dispersed also in the direction perpendicular to the radial direction, and the annular seal portion of the second layer is more preferably prevented from being partially deformed. .
That is, the annular seal portions of the first layer and the second layer (the same applies to the third layer when there are three or more layers) can be expanded and contracted in the inner diameter direction while maintaining a better circular shape. become.
[0027]
In the present invention, the plurality of seal members having the same shape and size before overlapping can be used.
[0028]
Further, the annular sealing device of the present invention can also be configured as a clamping device that seals and seals a sealing target by expanding and reducing the diameter of the annular sealing portion in the inner diameter direction (claim 5). ).
[0029]
【Example】
Next, embodiments of the present invention will be described in detail with reference to the drawings.
In FIGS. 1 and 2, reference numeral 10 denotes an annular sealing device which also serves as the clamping device of the present embodiment, and is a thin (here, about 2 mm) first annular first layer made of an elastic material such as rubber on the inner peripheral side. It has a seal member 12-1 and a second-layer seal member 12-2.
[0030]
On the outer peripheral side of these seal members 12-1 and 12-2, a metallic rigid member that holds each seal member 12-1 and 12-2 in a state of restricting deformation of an annular seal portion 26 described later in the outer radial direction is provided. An annular body 14 is arranged.
[0031]
The annular body 14 has an upper plate 16 and a lower plate 18 each having a circular ring shape, and an intermediate block 20 sandwiched therebetween, and these are fastened to each other in the axial direction by bolts 22. .
Then, the end portions 24 of the first-layer seal member 12-1 and the second-layer seal member 12-2 are sandwiched by the fastening force, and they are held.
[0032]
In this example, the seal member 12-1 of the first layer and the seal member 12-2 of the second layer have the same size and the same shape, respectively, and as shown in FIG. Each end 24 is sandwiched and held by the annular main body 14.
[0033]
These seal members 12-1 and 12-2 are formed such that a portion between the ends 24 fixed in a state of being clamped by the annular main body 14 bulges and contracts in the radial direction by elastic deformation. The seal portion 26 is provided.
[0034]
In this example, these seal members 12-1 and 12-2 are set on the annular main body 14 in a state of being superimposed on each other as shown in FIGS. It is kept in the attached state.
Here, the first-layer seal member 12-1 and the second-layer seal member 12-2 are in a state where the respective annular seal portions 26 and 26 are in close contact with each other in a state where they are overlapped with each other.
[0035]
In the present example, the sealing members 12-1 and 12-2 are in a non-adhered state throughout, but in some cases, each end portion 24, that is, a portion sandwiched and held by the annular main body 14, is mutually separated. It is also possible to keep them in a bonded state.
[0036]
In this example, the annular seal portion 26 in each of the seal members 12-1 and 12-2 has a shape which bulges in an arc shape toward the inner diameter side as shown in FIGS. 2 (B), 3 and 4. ing.
[0037]
As shown in FIG. 2 (B), a closed pressure chamber 28 is formed over the entire circumference between each of the annular seal portions 26 and the annular main body 14 in the seal members 12-1 and 12-2. Further, the annular main body 14 is provided with a supply hole 30 for supplying a pressurized fluid (here, pressurized air) to the pressure chamber 28 thereof.
[0038]
In the annular sealing device 10 of the present example, as shown in FIG. 5, a fluid is supplied from the supply hole 30 to the inside of the pressure chamber 28 with the sealing target (here, a round bar-shaped member) 32 inserted into the hollow portion thereof. The pressure is supplied to bring the pressure chamber 28 into a pressurized state.
[0039]
As a result, each of the annular seal portions 26 of the pair of seal members 12-1 and 12-2 expands and contracts in the radial direction with elastic deformation due to the pressure of the pressure chamber 28, and the inner periphery of the annular seal portion 26. The surface is brought into close contact with the entire periphery along the circular outer peripheral surface of the sealing target 32, and the outer peripheral surface of the sealing target 32 is sealed.
[0040]
When sealing is performed by expanding and reducing the diameter of the annular seal portion 26 in the radial direction, only one layer of the seal member 12 is provided, that is, a comparison shown in FIG. 6 in which a plurality of seal members are not provided in a superposed state. In the case of the example annular sealing device 10A, the pressure in the pressure chamber 28 causes wrinkles to occur in the sealing member 12, specifically the annular sealing portion 26, or a certain portion expands irregularly and partially more greatly than other portions. The inner peripheral shape cannot maintain a circular shape.
In FIG. 6, reference numeral 34 denotes a partially deformed portion of the annular seal portion 26.
[0041]
However, in the annular sealing device 10 of the present embodiment, the two sealing members 12-1 and 12-2 which are superposed, more specifically, the first-layer sealing member 12-1 and the second-layer sealing member 12-1. Each of the annular seal portions 26 of the seal member 12-2 uniformly swells and deforms in the radial direction over the entire circumference while maintaining a good circular shape, and closely contacts the outer peripheral surface of the sealing object 32 over the entire circumference. Thus, the outer peripheral surface of the sealing target 32 is sealed with high accuracy.
Further, each of the annular seal portions 26 is pressed against the outer peripheral surface of the sealing target 32 based on the pressure of the pressure chamber 28 and clamps them in a gripping state.
[0042]
As described above, in the annular seal device 10 of the present embodiment, the annular seal portion 26 can be swelled and reduced in diameter in the inner diameter direction, and the outer peripheral surface of the sealing target 32 can be sealed for the following reasons.
[0043]
That is, in this example, if a portion of the first-layer sealing member 12-1 in the circumferential direction of the annular seal portion 26 attempts to partially deform in the radial direction by the action of pressure, the second-layer sealing member The annular seal portion 26 of the member 12-2 acts as a resistance and acts to regulate partial deformation thereof.
[0044]
At this time, if the first-layer annular seal portion 26 and the second-layer annular seal portion 26 are bonded to each other, the circumferential portion of the second-layer annular seal portion 26 is also integrated with a certain portion in the circumferential direction. There is a possibility that the swelling deformation occurs partially.
However, in this example, since the second-layer annular seal portion 26 is not adhered to the first-layer annular seal portion 26, the second-layer annular seal portion 26 is not bonded to the first-layer annular seal portion. The local force or stress is dispersed in the circumferential direction while causing relative displacement in the circumferential direction with respect to the portion 26. As a result, the annular seal portion 26 has a good circular shape in both the first and second layers. It is possible to swell and reduce the diameter in the inner diameter direction while holding, so that the circular outer peripheral surface of the sealing object 34 can be sealed well.
[0045]
In the annular seal device 10 of the present embodiment, the amount of swelling / diameter deformation of the annular seal portion 26 can be freely controlled by the magnitude of the pressure applied to the pressure chamber 28, and therefore, when the outer diameter of the sealing object 34 changes variously. However, the outer peripheral surface of the object 34 to be sealed can be satisfactorily sealed using the same annular sealing device 10.
That is, it is possible to cope with various sizes of sealing objects 34 with the same annular sealing device 10.
[0046]
Furthermore, in the annular sealing device 10 of the present example, even if the outer peripheral surface of the sealing object 34 has some irregularities, the annular sealing portion 26 can be satisfactorily brought into close contact over the entire circumference. The outer peripheral surface of the object to be sealed can be satisfactorily sealed irrespective of the irregularities.
[0047]
The embodiment of the present invention has been described in detail above, but this is merely an example.
For example, in the above embodiment, the two sealing members are superposed, but in some cases, three or more sealing members can be superposed, and the shape of the annular seal portion is the inner diameter in the above example. Although the shape is such that it protrudes in an arc shape in the direction, it is also possible to form such an annular seal portion in various shapes other than the above examples.
[0048]
In the above example, a pair of seal members having the same size and the same shape are used, but the first-layer seal member 12-1 and the second-layer seal member 12-2 may be different depending on the case. The present invention can be configured in a form in which various changes are made without departing from the spirit thereof, for example, it is possible to use one having a different size or a different shape.
[Brief description of the drawings]
FIG. 1 is a diagram showing an annular sealing device according to an embodiment of the present invention in an external appearance state.
FIG. 2 is a plan view and a longitudinal sectional view of the annular sealing device of the embodiment.
FIG. 3 is an explanatory diagram showing an assembling procedure of the annular sealing device of the embodiment.
FIG. 4 is a view showing two annular sealing members in the annular sealing device of the embodiment in a state where they are separated from each other and in a state where they are overlapped.
FIG. 5 is an explanatory view of the operation of the annular sealing device of the embodiment.
FIG. 6 is a comparative example diagram showing a comparative example of the annular sealing device.
FIG. 7 is an explanatory diagram for explaining the background of the present invention.
[Explanation of symbols]
Reference Signs List 10 annular sealing device 12-1, 12-2 sealing member 14 annular body 26 annular sealing portion 28 pressure chamber 30 supply hole 32 sealing target

Claims (5)

(A) a seal member having an annular seal portion which is elastic and has a thin annular shape and which expands and contracts in the radial direction over the entire circumference by the action of pressure; and (b) an outer peripheral side of the seal member. A rigid annular main body arranged to hold the sealing member in a state of restricting deformation of the annular sealing portion in the outer radial direction; and (c) a hermetically sealed and annular shape formed between the annular sealing portion and the annular main body. A pressure chamber, and (d) a supply hole for supplying a pressurized fluid to the pressure chamber,
The seal members are overlapped with each other so as to form at least two layers in the radial direction and the respective annular seal portions are in a non-adhered state. An annular sealing device, which bulges into a substantially circular outer peripheral surface to be sealed and seals over the entire circumference. 2. The annular sealing device according to claim 1, wherein a cross-sectional shape of the annular sealing portion has a shape protruding in an arc shape toward an inner diameter side. The annular seal device according to any one of claims 1 and 2, wherein the annular seal portions of at least two layers of the seal member are superimposed on each other in close contact with each other. 4. The annular sealing device according to claim 3, wherein the plurality of sealing members have substantially the same size and shape before overlapping. The annular seal device according to any one of claims 1 to 4, wherein the annular seal portion also serves as a clamp device for gripping the sealing target on the outer peripheral surface by expanding and reducing the diameter of the annular seal portion in the inner diameter direction. An annular sealing device, characterized in that:

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