JP2003014131A - Rotary shaft sealing device - Google Patents

Abstract

(57) [Summary] A sleeve support member (9) and a sleeve (7) absorb thermal expansion of a seal member or the like and prevent slidability from being deteriorated.
A seal case 22 that covers the periphery of the rotating shaft 4 is formed.
On both sides in the axial direction of the seal case 22, annular members 24 and 25 inserted from the open sides of the annular seal members 23A to 23C are arranged. Between the annular members 24 and 25,
The annular seal members 23A to 23C are arranged with their closed sides facing each other. Facing annular seal members 23A-2
3C, at high temperatures, the annular sealing members 23A to 23C
Is deformed by thermal expansion, an intermediate spacer 27 for absorbing the deformation is provided.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shaft sealing device, and more particularly to a rotary shaft seal provided in a liquid storage tank for storing a filling liquid such as a beverage. It concerns the device. 2. Description of the Related Art A filler storage tank (filler bowl) for filling a container is provided with a stirrer for stirring the filling liquid, and a rotating shaft provided with a stirring blade at a tip is provided with a filler bowl. Is positioned in the filling liquid by penetrating through the top surface, and is rotated by a motor provided outside. A seal device is provided on such a rotating shaft, and the sliding portion is closed to prevent foreign matter from being mixed into the filling liquid. [0003] Conventionally, an O-ring has been used as such a sealing device. However, since the O-ring is in surface contact with the rotating shaft, frictional heat is likely to be generated, and in the case of a filler bowl stirring device,
Since the rotating shaft itself is also heated to a high temperature by the high-temperature filling liquid, there is a problem that the O-ring thermally expands, the sealing force is increased, and the sliding property of the rotating shaft is deteriorated. [0004] The present invention has been made to solve the above-mentioned problems, and has as its object to provide a rotary shaft sealing device which is hardly affected by thermal expansion. [0005] A rotary shaft sealing device according to the present invention includes a seal case provided on the fixed side to cover the circumference of the rotary shaft, and surrounds the rotary shaft in the seal case and has a cross section. An annular seal member formed in a substantially V-shape and having an open side that can be opened, and an annular member that is inserted into the open side of the annular seal member and that opens the open side,
The annular members are arranged on both axial sides in the seal case, and the annular seal members into which the annular members are inserted are arranged with their closed sides facing each other, and the thermal expansion of the annular seal members is absorbed between the opposed annular seal members. It is characterized in that an elastic member is interposed. [0006] In the rotary shaft sealing device according to the present invention, the annular sealing member having a V-shaped cross section is provided in a double manner so as to have different directions in the axial direction. Can also be reliably sealed. Further, since the annular seal member comes into line contact with the rotating shaft, slidability of the rotating shaft is good, and generation of frictional heat can be suppressed. For example, even if the annular seal member is heated to a high temperature and thermally expanded, the elastic member absorbs deformation due to heat, so that good sealing performance can be maintained without deteriorating slidability. The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 is a diagram showing the overall configuration of a stirring device provided with a rotary shaft sealing device according to an embodiment of the present invention, and FIG. 2 is a sectional view showing the rotary shaft sealing device of FIG. As shown in FIG. 1, the stirrer 2 for stirring the filling liquid in the filler bowl 1 includes a top plate 8A of the filler bowl 1.
Shaft 4 rotatably supported on a support 8 fixed to the
And a stirring blade 5 attached to a lower portion of the rotating shaft 4.
And a rotation driving device 6 provided at the upper end of the rotation shaft 4 for driving the rotation shaft 4 to rotate. A sleeve 7 is attached to the support base 8 via a sleeve support member 9, and the rotating shaft 4 is attached to the sleeve 7 by bushes 11, 12.
Is to be inserted through. Sleeve 7 is
It is placed on a protruding edge 10 formed at the lower end of the sleeve support member 9 so as to protrude inward, and is attached to the sleeve support member 9. The bushes 11 and 12 are made of synthetic resin, and are mounted on the upper and lower portions of the sleeve 7. A seal device 20 is provided below the lower bush 12 on the sleeve 7 and the sleeve support member 9. Reference numeral 3 denotes a part of the side wall of the filler bowl 1. As shown in FIG. 2, a sleeve (fixed side) 7
The seal case 22 is rotated by the enlarged diameter portion 21 of which the inner diameter is enlarged at the lower portion of the sleeve and the protruding edge portion 10 of the sleeve support member (fixed side) 9 at which the lower end of the sleeve 7 is in contact and closes the lower side of the enlarged diameter portion 21 4 is formed so as to cover the periphery. The sealing device 20
An annular seal member 23 surrounding the rotating shaft 4 in a seal case 22 formed by the sleeve 7 and the protruding edge 10.
A, 23B, and 23C are arranged. Annular seal members 23A, 23B, 23C
Is formed to have a substantially V-shaped cross section, the inner peripheral edge of which is in line contact with the rotating shaft 4 for sealing, and the open side of the V-shape can be expanded by flexibility. In the present embodiment, as shown in FIG. 2, the annular seal members 23A to 23C are arranged such that the upper annular seal member 23A and the lower annular seal member 23B face the V-shaped closed sides. The closed side is inserted below the lower annular seal member 23B and the open side thereof is inserted below the lower annular seal member 23B.
Are arranged so as to overlap the annular seal member 23B. The upper annular seal member 23A is directed upward on the open side, and the lower annular seal members 23B and 23C are directed downward on the open side. The upper annular seal member 23A and the stacked lower annular seal members 23B and 23C are stacked. Among them, the annular members 24 and 25 are inserted from the open side to the closed side of the annular seal member 23C located on the lower side.
In addition, as a material of the annular seal members 23A to 23C,
Poly-tetra-fluoro-ethylene or polyetheretherketone (PEEK)
23C may be all made of the same material, or a combination of both materials may be used. As shown in FIG. 2, the annular members 24 and 25 are formed in an annular shape having a substantially L-shaped cross section, and are made of polyetheretherketone (PEEK). The annular members 24 and 25 are arranged on both axial sides of the seal case 22 with the annular seal members 23A to 23C interposed therebetween, and are inserted into the open sides of the annular seal members 23A and 23C. The annular members 24 and 25 are formed with projecting edges 24A and 25A projecting outward. The outer peripheral surfaces of these protruding edges 24A and 25A are in contact with the inner peripheral surface of the enlarged diameter portion 21 of the sleeve 7. An annular spacer (shim) 26 is interposed between the upper annular member 24 and the axially upper surface 22A in the seal case 22. Further, the sealing device 20 is provided with an intermediate spacer (elastic member) 27 for absorbing the thermal expansion of the annular seal members 23A to 23C between the annular seal members 23A and 23B facing each other. The intermediate spacer 27
It is made of ultra-high molecular weight polyethylene which is annular and formed in a U-shaped or W-shaped cross section and is deformable in the axial direction.
The intermediate spacer 27 is provided with annular sealing members 23A to 23A.
Even if C becomes hot and thermally expands and displaces in the axial direction, it has elasticity capable of absorbing the displacement. The annular seal members 23A to 23C, the annular members 24 and 25, and the intermediate spacer 27 are arranged in the enlarged diameter portion 21 of the sleeve 7 as shown in FIG. In this state, the lower annular member 25 and the annular seal member 23C are in a state of protruding without entering the enlarged diameter portion 21. In this state, the sleeve 7 is inserted into the sleeve support member 9 surrounding the sleeve 7 and fixed. As a result, the protruding edge 10 of the sleeve support member 9 pushes these members into the enlarged diameter portion 21 and the seal case 22
It is designed to be held within. That is, each open side of the annular seal members 23A to 23C is expanded by the annular members 24 and 25 due to the flexibility thereof, and is also entirely compressed by the elasticity of the intermediate spacer 27 to form the seal case 2.
Some are kept in 2. At this time, the pressure contact force (seal force) of the inner peripheral edge to the rotating shaft 4 is determined by the opening amount of the annular seal members 23A to 23C on the expanding side, but if this is weak, the necessary sealing property cannot be obtained. If it is too strong, the sealing force increases, but the slidability of the rotating shaft 4 deteriorates, and a necessary rotating force according to the capability of the rotary drive device 6 cannot be obtained.
An appropriate thickness and number of spacers 26 are selected and optimally interposed between the annular member 24 and the surface 22A of the seal case 22 (the enlarged diameter portion 21) or between the annular member 25 and the protruding edge 10. It adjusts to a proper sealing force. The elastic force of the intermediate spacer 27 is set so as to absorb the thermal expansion of the annular seal members 23A to 23C and the annular members 24 and 25 from this state and further compress the annular seal members 23A to 23C. Next, the sealing device 2 according to the above embodiment will be described.
The operation of 0 will be described. When the stirring device 2 is operated and the rotation driving device 6 drives the rotation shaft 4 to rotate, the rotation shaft 4
The stirring blade 5 at the lower end is rotated, and the filler bowl 1 (not shown)
The filling liquid inside is stirred. The rotating shaft 4 is rotatably driven while being supported by bushes 11 and 12 made of synthetic resin. In the event that abrasion powder is generated from the bushes 11 and 12, the abrasion powder falls downward and enters the seal case 22 of the seal device 20. The wear powder that has entered from the upper part of the seal case 22 is guided and collected inside the upper annular seal member 23A on the open side facing upward. Should be upper annular seal member 23A
From the lower annular seal member 23
As it is designed to double seal with B, 23C,
Sealing can be performed reliably. Although frictional heat is generated with the rotation of the rotary shaft 4, the present invention provides an annular seal member 2 having a V-shaped cross section.
3A to 23C are adopted, and the inner peripheral edge thereof is in line contact with the rotating shaft 4, so that the amount of heat generation is suppressed as compared with the case of surface contact. Further, even when the temperature of the annular seal members 23A to 23C becomes high, the annular seal members 23A to 23C
Is thermally expanded while maintaining the V-shaped cross section,
Displaces in the axial direction while maintaining line contact with Even if the upper annular seal member 23A and the lower annular seal members 23B and 23C are respectively displaced in the axial direction, the displacement on both sides in the axial direction in the seal case 22 is regulated by the annular members 24, 25 and the spacer 26. It is displaced toward the center of the case 22, that is, toward the intermediate spacer 27. The intermediate spacer 27 is elastically provided with the annular seal member 2.
Absorbs displacements of 3A to 23C. For this reason, even if the temperature of the annular seal members 23A to 23C becomes high, the displacement caused by the thermal expansion is absorbed by the intermediate spacer 27, so that the sealability is always improved without deteriorating the slidability of the rotary shaft 4. Can be maintained. In the above embodiment, one spacer is interposed between the upper annular member 24 and the seal case 22. However, the present invention is not limited to this.
6, the annular sealing members 23A to 23
By adjusting the degree of adhesion of 23C, an optimum sealing force can be obtained. Further, the thickness of the spacer 26 in the axial direction can be changed and adjusted, and when the annular sealing member is deteriorated, it can be replaced with a thicker one to enhance the sealing performance.
In the above embodiment, the annular seal members 23A to 23A-2
Each of the 3Cs is arranged in a different direction, one on the upper side and two on the lower side. However, the present invention is not limited to this. If so, the number of the annular seal members may be changed on each of the upper and lower sides. Furthermore, although the sealing device according to the above-described embodiment has been described with respect to the sealing device used for the stirring device that stirs the filling liquid in the filler bowl of the filler, the sealing device is not limited to this, and may have a rotating shaft. Needless to say, it can be applied to shaft seals in other fields. As described above, according to the present invention, a seal case that covers the periphery of a rotating shaft and is provided on a fixed side,
An annular sealing member that surrounds the rotating shaft in the seal case, has a substantially V-shaped cross section, and is openable on the open side; and an annular member that is inserted into the open side of the annular seal member and expands the open side. The annular members are arranged on both sides in the axial direction in the seal case, the annular seal members into which the annular members are inserted are arranged with their closed sides facing each other, and the heat of the annular seal members is placed between the opposed annular seal members. Since the elastic member that absorbs expansion is interposed, thermal expansion of the seal member and the like can be absorbed, and deterioration of slidability can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing the overall configuration of a stirring device provided with a rotary shaft sealing device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the rotary shaft sealing device of FIG. 1; [Description of Signs] 4 Rotating shaft 7 Sleeve (fixed side) 9 Sleeve support member (fixed side) 22 Seal cases 22A to 23C Ring seal members 24 and 25 Ring member 27 Intermediate spacer (elastic member)

Continuation of front page    (72) Inventor Tatsuhiro Nakata             58 Kou, Ozuda-Honmachi, Kanazawa-shi, Ishikawa Shibuya             Industry Co., Ltd. (72) Inventor Satoshi Iriguchi             58 Kou, Ozuda-Honmachi, Kanazawa-shi, Ishikawa Shibuya             Industry Co., Ltd. F term (reference) 3J043 AA17 BA02 BA08 CA02 CA06                       DA02

Claims (1)

Claims: 1. A seal case which covers the periphery of a rotary shaft and is provided on a fixed side, and which surrounds the rotary shaft in the seal case, has a substantially V-shaped cross section, and has an open side which is enlarged. An annular seal member that can be opened, and an annular member that is inserted into the open side of the annular seal member and expands the open side,
The annular members are arranged on both axial sides in the seal case, and the annular seal members into which the annular members are inserted are arranged with their closed sides facing each other, and the thermal expansion of the annular seal members is absorbed between the opposed annular seal members. A sealing device for a rotating shaft, wherein an elastic member is interposed.