JP2008281028A - Shaft seal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable excellent maintenance of sealabilities of a gland packing for a run-out of a rotary shaft in a shaft seal device equipped with the gland packing to seal a portion through which the rotary shaft penetrates. <P>SOLUTION: The shaft seal device (2) comprises a cylindrical seal retainer (10) housing a ground packing (8), and an annular elastic body (12) positioned radially outward of the seal retainer (10) having the inside mounted on the seal retainer (10) and the outside mounted on a penetration portion (6) of the rotary shaft (4) respectively, following the movement of the seal retainer (10) due to the change of the rotary shaft (4), and elastically deforming. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shaft sealing device including a gland packing that seals a portion through which a rotating shaft passes, and more particularly to a shaft sealing device suitable for sealing a rotating shaft with a large runout.

  As a device for sealing a rotating shaft that penetrates a container containing powder, fluid, or the like, there is a well-known shaft sealing device in which a seal holder that contains a gland packing is attached to a penetrating portion of the container (for example, Patent Document 1). FIG. 1).

  As an example of use of this shaft seal device, for example, there is a screw feeder for transferring powder (see Patent Document 1 and FIG. 3). A known screw feeder includes a long rotating shaft with spiral blades attached to the outer periphery in a long cylindrical container, and the rotating shaft is supported at both ends by bearings on the container. The through portion is sealed by a shaft seal device so that the powder in the container does not leak out or foreign matter does not enter from the outside. The rotating shaft is rotationally driven by an external driving means.

A powder inlet is provided on one side in the longitudinal direction of the container, a hopper containing powder is connected to the powder inlet, and the powder is provided on the other side of the container by rotating the rotary shaft. To the powder outlet.
Japanese Patent Laid-Open No. 2002-22018 (FIGS. 1 and 3)

  The conventional shaft seal device in the form as described above has the following problems to be solved.

  That is, particularly in a structure such as a screw feeder where both ends of a long rotating shaft are supported by bearings and provided with a shaft seal device, the rotating shaft is elastically bent by a load such as powder to be transferred, In addition, when the powder to be transported is hot, it is stretched and deformed by heat. Therefore, if the runout of the rotating shaft is large and the runout is, for example, 0.1 mm or more, the gland packing is likely to be worn away and leakage is likely to occur. Also, the frequency of maintenance such as replacement of the gland packing and retightening increases.

  The present invention has been made in view of the above-described facts, and a technical problem thereof is a seal for a gland packing against a runout of the rotary shaft in a shaft seal device having a gland packing that seals a portion through which the rotary shaft passes. It is to provide a shaft seal device capable of maintaining good performance.

  According to the present invention, as a shaft seal device having a gland packing that seals a portion through which the rotating shaft passes, a cylindrical seal holder that accommodates the gland packing and a ring-shaped outer ring in the radial direction of the seal holder. And an annular elastic body that is elastically deformed following the movement of the seal holder due to the fluctuation of the rotation shaft, and is provided with an inner side attached to the seal holder and an outer side attached to the penetrating portion. A shaft seal device is provided.

  In a first preferred embodiment, the annular elastic body is formed in a donut disk shape extending in a direction orthogonal to the axis of the rotation shaft, and the radially inner flange portion and the outer flange portion of the donut disk shape are sealed. Attached to cage and penetration. Further, a bent portion is provided between the inner flange portion and the outer flange portion.

  In a second preferred embodiment, the annular elastic body includes a cylindrical portion fitted to the outer peripheral portion of the seal holder, and extends integrally from the cylindrical portion in a direction orthogonal to the axis of the rotation shaft. And a flange portion attached to the housing.

  In a third preferred embodiment, the annular elastic body is formed in the shape of a bellows that extends in the axial direction of the rotating shaft, and one side in the axial direction is the seal holder and the other side is the penetrating portion. Installed.

  Each of the above-described annular elastic bodies seals between the penetrating portion and the seal holder.

  A shaft seal device having a gland packing configured to seal the penetrating portion of the rotary shaft, which is configured according to the present invention, is provided with a seal holder that accommodates the gland packing, and an annularly positioned inside the seal holder in the radial direction. Are provided with annular elastic bodies that are attached to the penetrating portions on the outside and that elastically deform following the movement of the seal holder due to fluctuations in the rotation axis.

  Accordingly, since the seal holder that accommodates the gland packing is attached to the penetrating portion of the rotating shaft via the annular elastic body, the seal holder can move following the fluctuation of the rotating shaft. The sealing property of the gland packing can be maintained well.

  Hereinafter, a shaft seal device constructed according to the present invention will be described in more detail with reference to the accompanying drawings illustrating preferred embodiments.

  A first embodiment will be described with reference to FIG. A shaft sealing device including a gland packing 8 that seals the penetrating portion 6 of the rotary shaft 4, which is indicated by the whole number 2, includes a cylindrical seal holder 10 that accommodates the gland packing 8, and the seal holder 10. An annular elastic body that is annularly positioned radially outward, the inner side is attached to the seal holder 10 and the outer side is attached to the penetrating portion 6, respectively, and elastically deforms following the movement of the seal holder 10 due to the fluctuation of the rotating shaft 4. 12 is provided.

  The through portion 6 of the rotating shaft 4 has, for example, a through hole 6b in a side wall 6a of a container containing the powder P.

  The seal holder 10 is made of stainless steel, and has a cylindrical portion 10a that accommodates the gland packing 8, and a disk-like shape that extends radially inward on one side in the longitudinal direction of the cylindrical portion 10a (left side in FIG. 1). The packing latching | locking part 10b and the disk-shaped flange part 10c extended in radial direction outward are provided in the other side (right side of FIG. 1).

  The gland packing 8 includes two sets of packing sets each including a plurality of V packings 8a, and includes a spacer ring 8b that forms a space for storing grease between the two sets. The V packing 8a is formed of a fluororesin containing glass fiber, and is accommodated with the seal lip facing the powder P side of the container. Grease is supplied to the space of the spacer ring 8b through a pipe (not shown).

  The annular elastic body 12 is formed of silicon rubber or fluorine rubber in a donut disk shape extending in a direction orthogonal to the axis X of the rotating shaft 4, and is bent in an annular shape in the radial direction between the inner flange portion 12a and the outer flange portion 12b. A portion 12c is provided. The bent portion 12c is formed in a hollow circular tube. The annular elastic body 12 is filled with a reinforcing material 12d made of glass fiber or the like.

  Each of the inner flange portion 12a and the outer flange portion 12b is provided with a plurality of (for example, eight) bolt holes on a pitch circle centered on the axis X, and the annular elastic body 12 has a plurality of through the bolt holes. The bolts 14 are attached to the flange portion 10 c of the seal holder 10 and the side wall 6 a of the penetrating portion 6.

  The annular elastic body 12 formed in a donut shape is sealed so that, for example, the powder P of the container does not leak through the through hole 6b between the through portion 6 and the seal holder 10 in the attached state. Is formed.

  A seal retainer 16 that presses the gland packing 8 in the direction of the axis X from the flange portion 10c side is attached to the seal holder 10 so that the pressing force can be adjusted by a plurality of (for example, six) bolts 18. .

  FIG. 2 shows a state where an annular elastic body 20 as a modification of the annular elastic body 12 is attached. The annular elastic body 20 is the same as the annular elastic body 12 except that the shape of the bent portion 20a is different from the bent portion 12c of the annular elastic body 12. The bent portion 20a is formed in a semicircular shape instead of a hollow circular tube.

  With reference to FIG. 1, the effect of the shaft seal apparatus 2 as mentioned above is demonstrated.

  The shaft seal device 2 includes a seal holder 10 that accommodates the gland packing 8, and is positioned annularly on the radially outer side of the seal holder 10, with the inner side being the seal holder 10 and the outer side being the penetrating portion 6 of the rotating shaft 4. An annular elastic body 12 (20) that is attached and elastically deforms following the movement of the seal holder 10 due to the fluctuation of the rotating shaft 4 is provided. Therefore, since the seal holder 10 is attached to the penetrating portion 6 via the annular elastic body 12 (20), the seal holder 10 can fluctuate according to the movement of the rotating shaft 4 in the radial direction or the axis X direction, The sealing performance of the gland packing 8 can be maintained well against the runout of the rotating shaft 4.

  The annular elastic body 12 (20) is formed in a donut disk shape extending in a direction orthogonal to the axis X of the rotating shaft 4, and the inner flange portion 12a and the outer flange portion 12b of the donut disk shape are respectively connected to the seal holder 10 and Since it is attached to the penetrating portion 6, even if the center deflection direction of the rotary shaft 4 changes, the core deflection can be easily and appropriately absorbed.

  Moreover, the annular elastic body 12 (20) can absorb the runout of the rotating shaft 4 more easily by providing the bent portion 12a (20a) between the inner flange portion 12b and the outer flange portion 12a.

  Further, since the annular elastic body 12 (20) is formed so as to seal between the penetrating part 6 and the seal holder 10, for example, powder P of the container does not leak through the penetrating part 6 or externally. It is possible to seal completely and easily so that no foreign matter enters from the inside.

  A second embodiment will be described with reference to FIG. Note that substantially the same parts as the shaft seal device 2 described above, for example, the rotating shaft 4, the penetrating part 6, the gland packing 8, the packing presser 16, and the like are denoted by the same reference numerals and description thereof is omitted.

  The shaft seal device generally indicated by reference numeral 22 has a cylindrical seal holder 24 that accommodates the gland packing 8, and is positioned annularly on the outer side in the radial direction of the seal holder 24. An annular elastic body 26 that is attached to each of the penetrating portions 6 of the rotating shaft 4 and elastically deforms following the movement of the seal holder 24 due to the fluctuation of the rotating shaft 4 is provided.

  The seal holder 24 is made of stainless steel, and has a cylindrical portion 24a that accommodates the gland packing 8 and a disk-like shape that extends radially inwardly on one side in the longitudinal direction of the cylindrical portion 24a (left side in FIG. 3). A packing locking portion 24b and a disc-shaped flange portion 24c extending radially outward are provided on the other side (the right side in FIG. 3).

  The annular elastic body 26 is formed of silicon rubber or fluororubber, and a cylindrical portion 26a fitted and baked on the outer surface of the cylindrical portion 24a and the packing locking portion 24b of the seal retainer 24, and a rotating shaft from the cylindrical portion 26a. 4, and a flange portion 26 b that integrally extends in a direction orthogonal to the axis X of 4 and is baked and joined to the flange portion 24 c of the seal holder 24. A cylinder 28 made of stainless steel is integrally baked and joined to the outer peripheral portion of the cylindrical portion 26a. Therefore, the cylindrical portion 26a of the annular elastic body 26 is sandwiched integrally between the seal holder 24 and the cylinder 28 in a sandwich shape.

  Each of the flange portion 24c of the seal holder 24 and the flange portion 26b of the annular elastic body 26 is provided with a plurality of (for example, eight) bolt holes on a pitch circle with the axis X as the center. With the plurality of bolts 14, the seal holder 24 is attached to the side wall 6 a of the penetrating portion 6 with the flange portion 26 b of the annular elastic body 26 interposed therebetween.

  The annular elastic body 26 is formed so as to seal between the penetrating portion 6 and the seal holder 24 so that, for example, the powder P of the container does not leak through the through hole 6b in the attached state.

  With reference to FIG. 3, the effect of the shaft seal device 22 as described above will be described.

  The shaft seal device 22 is positioned annularly on the radially outer side of the seal holder 24 that accommodates the gland packing 8, the inner side being the seal holder 24, and the outer side being the penetrating portion 6 of the rotating shaft 4. An annular elastic body 26 that is attached and elastically deforms following the movement of the seal holder 24 due to the fluctuation of the rotating shaft 4 is provided. Accordingly, since the seal holder 24 is attached to the penetrating portion 6 via the annular elastic body 26, the seal holder 24 can be changed according to the movement of the rotating shaft 4 in the radial direction or the axis X direction. Therefore, the sealing performance of the gland packing 8 can be maintained satisfactorily.

  The annular elastic body 26 includes a cylindrical portion 26a, which is an outer peripheral portion of the seal holder 24, fitted into the cylindrical portion 24a and the packing locking portion 24b and baked, and the axis X of the rotary shaft 4 from the cylindrical portion 26a. Since the flange portion 26b is baked on the flange portion 24c of the seal retainer 24 and is formed in a cylindrical shape with a flange, even if the center runout direction of the rotary shaft 4 changes. The core runout can be easily absorbed appropriately.

  Further, since the annular elastic body 26 is formed so as to seal between the penetrating part 6 and the seal holder 24, the powder P of the container does not leak through the penetrating part 6 with a simple cylindrical structure. In addition, it can be completely and easily sealed so that foreign matter does not enter from the outside.

  A third embodiment will be described with reference to FIG. Note that substantially the same parts as the shaft sealing devices 2 and 22, for example, the rotating shaft 4, the penetrating part 6, the gland packing 8, the packing retainer 22, and the like are denoted by the same reference numerals and description thereof is omitted.

  A shaft seal device generally indicated by reference numeral 30 has a cylindrical seal holder 32 that accommodates the gland packing 8, and is positioned annularly on the outer side in the radial direction of the seal holder 32. An annular elastic body 34 that is attached to each of the penetrating portions 6 of the rotating shaft 4 and elastically deforms following the movement of the seal holder 32 due to the fluctuation of the rotating shaft 4 is provided.

  The seal holder 32 is made of stainless steel, and has a cylindrical portion 32a that houses the gland packing 8, and a disk-like shape that extends radially inward on one side in the longitudinal direction of the cylindrical portion 32a (left side in FIG. 1). A packing locking portion 32b and a disk-like flange portion 32c extending radially outward are provided on the other side (right side in FIG. 1).

  The annular elastic body 34 is formed of stainless steel into a bellows-shaped bellows extending in the direction of the axis X of the rotary shaft 4, and a disc-shaped portion 34 a extending inward on one side (left side) in the direction of the axis X is sealed. Disc-like portions 34 b extending outwardly on the other side (right side) are attached to the cage 32 on the side walls 6 a of the penetrating portions 6, respectively.

  The disc-shaped portion 34a is integrally joined to and attached to the outer peripheral portion of the cylindrical portion 32a of the seal holder 32, and a plurality of disc-shaped portions 34b are provided on the side wall 6a on a pitch circle around the axis X. A plurality of bolts 14 (e.g., eight) are attached with a washer 36 made of silicon rubber sandwiched between the side wall 6a.

  The annular elastic body 34 is formed so as to seal between the penetrating portion 6 and the seal holder 32 so that, for example, the powder P of the container does not leak through the through hole 6b in the attached state.

  With reference to FIG. 4, the effect of the shaft seal apparatus 30 as mentioned above is demonstrated.

  The shaft seal device 30 is arranged in a ring shape on the radially outer side of the seal holder 32 that accommodates the gland packing 8, the inner side being the seal holder 32, and the outer side being the penetrating portion 6 of the rotating shaft 4. An annular elastic body 34 that is attached and elastically deforms following the movement of the seal holder 32 due to the fluctuation of the rotating shaft 4 is provided. Therefore, since the seal holder 32 is attached to the penetrating portion 6 of the rotary shaft 4 via the annular elastic body 34, the seal holder 32 can be changed according to the movement of the rotary shaft 4 in the radial direction or the axis X direction. The sealing performance of the gland packing 8 can be maintained well against the runout of the rotating shaft 4.

  The annular elastic body 34 is a bellows formed in a bellows-like shape extending in the axis X direction of the rotating shaft 4, and a disk-like portion 34 a extending inward on one side (left side) in the axis X direction is sealed. Since the disc-like portion 34b extending outwardly on the other side (right side) is attached to the cage 32 on the retainer 32, the runout is easy even if the runout direction of the rotary shaft 4 changes. Can be absorbed properly.

  Further, since the annular elastic body 34 is formed so as to seal between the penetrating portion 6 and the seal holder 32, the powder P of the container does not leak through the penetrating portion 6 with a simple bellows cylinder structure. Thus, it can be completely and easily sealed so that no foreign matter enters from the outside.

  By using two shaft sealing devices 2, 22, and 30 described in detail above in combination in the direction of the axis X, the sealing performance by the shaft sealing device in the portion through which the rotary shaft 4 passes can be further improved.

  For example, referring to FIG. 5, in this embodiment, a shaft sealing device 201 having substantially the same configuration as that of the shaft sealing device 2 is provided on the side of the container containing, for example, the powder P, and the outer side in the axis X direction. A shaft seal device 202 having substantially the same configuration as that of the shaft seal device 2 is provided.

In the space between the shaft seal device 201 and the shaft seal device 202, and the space where the O-ring seal 204 is attached to the container side on the radially outer side of the seal holder 10 of the shaft seal device 201, N as a seal gas is externally provided. _Two gases are introduced and sealed (arrow N ₂ ). By making the pressure of this gas slightly higher than the pressure in the container, the leakage of the powder P to the outside and the entry of foreign matter from the outside can be better prevented. Further, the space of the spacer ring 8b of each gland packing 8 is supplied and filled with grease from the outside (arrow G). This grease can suppress wear of the gland packing 8 and prevent leakage and entry of foreign matter.

  6 shows a shaft sealing device 220 having substantially the same configuration as that of the shaft sealing device 22 on the side where, for example, the powder P is contained in the container, and substantially the same configuration as that of the shaft sealing device 2 on the outer side in the axis X direction. The shaft seal device 203 is provided.

In the space between the shaft seal device 220 and the shaft seal device 203, N ₂ gas as a seal gas is introduced and sealed from the outside (arrow N ₂ ). Further, the space of the spacer ring 8b of each gland packing 8 is supplied and filled with grease from the outside (arrow G).

  The present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various changes or modifications can be made within the scope of the present invention, for example, as described below. Is.

  In the embodiment of the present invention, the gland packing 8 is provided with two sets of packing sets composed of the V packing 8a, and is provided with a spacer ring 8b for retaining grease between them, but the gland packing is limited to this embodiment. For example, so-called shaft seal packing such as square packing, square braided packing, square spiral packing, oil seal, or dust seal may be used alone or in combination. Needless to say.

  In the shaft seal device 2 according to the embodiment of the present invention, the annular elastic body 12 (20) includes the bent portion 12c (20a) between the inner flange portion 12a and the outer flange portion 12b. If you don't need it, you don't have to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating a configuration of a first embodiment of a shaft seal device configured according to the present invention. The structure explanatory sectional view of other forms of the shaft seal device of the 1st example. FIG. 6 is a cross-sectional view illustrating the configuration of a second embodiment of the shaft seal device configured according to the present invention. The structure explanatory sectional view of the 3rd example of the shaft seal device constituted according to the present invention. The Example which combined two shaft seal apparatuses comprised according to this invention. Another embodiment in which two shaft sealing devices constructed according to the present invention are combined.

Explanation of symbols

2: Shaft seal device 4: Rotating shaft 6: Penetration part 8: Gland packing 10: Seal holder 12: Elastic annular body 12a: Inner flange part 12b: Outer flange part 12c: Bent part 20: Annular elastic body 20a: Bent part 22: shaft sealing device 24: seal holder 26: annular elastic body 26a: tube portion 26b: flange portion 30: shaft sealing device 32: seal holder 34: annular elastic body 34a: one side portion 34b: other side portion 201, 202, 203, 220: Shaft seal device

Claims (6)

A shaft seal device having a gland packing that seals a portion through which the rotating shaft passes,
A cylindrical seal holder that houses a gland packing that slidably contacts the outer periphery of the rotating shaft;
Annularly located radially outside the seal cage, the inside is attached to the seal cage and the outside is attached to the penetrating portion, and the ring is elastically deformed following the movement of the seal cage due to the fluctuation of the rotating shaft. A shaft seal device comprising an elastic body. The annular elastic body is
Formed in the shape of a donut extending in a direction orthogonal to the axis of the rotation axis,
The shaft seal device according to claim 1, wherein the inner flange portion and the outer flange portion in the radial direction of the donut disk shape are respectively attached to the seal holder and the penetrating portion. The shaft seal device according to claim 2, wherein a bent portion is provided between the inner flange portion and the outer flange portion. The annular elastic body is
A cylinder portion fitted to the outer peripheral portion of the seal retainer, and a flange portion integrally extending from the cylinder portion in a direction orthogonal to the axis of the rotary shaft and attached to the penetrating portion. Item 10. The shaft seal device according to Item 1. The annular elastic body is
Formed in the shape of a bellows extending in the axial direction of the rotation axis,
The shaft seal device according to claim 1, wherein one side portion in the axial direction is attached to the seal holder and the other side portion is attached to the penetrating portion. The annular elastic body is
The shaft seal device according to any one of claims 1 to 5, wherein a space between the penetrating portion and the seal holder is sealed.

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