JP2010127416A - Sealing structure of rotation shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing structure of a rotation shaft with the small number of components, allowing easy maintenance, at a place where the rotatingly driven rotation shaft penetrates a casing. <P>SOLUTION: The sealing structure of the rotation shaft includes a mixing tank wall 4 for storing mixture 2, the rotation shaft 5 penetrating the mixing tank wall 4, a circular rotation side sliding element 14 provided around the rotation shaft 5, a fixed-side sliding element 19 which is a cylindrical member surrounding the rotation shaft 5 via a clearance 36 and contacts the rotation side sliding element 14 on its inner end surface 35, a pressing panel 24 which is a flat-plate member fixed to an outer end surface of the fixed-side sliding element 19, a fixing bolt 25 inserted through the pressing panel 24 with its discal end part fixed to the mixing tank wall 4, a pressing force adjustment nut 26 screwed with the fixing bolt 25, a biasing spring 27 for biasing the pressing panel 24 to the mixing tank wall 4 side, and a bearing provided on the outer side from the fixing bolt 25 to rotatably support the rotation shaft 5. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a seal structure for preventing the contents in the casing from leaking to the outside from the gap between the rotary shaft and the casing at a location where the rotary shaft to be rotated passes through the casing. The present invention relates to a seal structure with a small number of points and easy maintenance.

  In a mixer or the like that stirs a mixture, a rotating shaft that has a stir bar and is driven to rotate is provided through a casing that constitutes the mixer. In this through portion, a slight gap is provided between the two so that the rotating shaft does not contact the casing. Therefore, a seal structure is required to prevent the mixture inside the casing from leaking out of the gap. As this rotary shaft seal structure, a so-called mechanical seal is conventionally used. In this mechanical seal, an annular seal member is fixed to the peripheral surface of the rotating shaft, while an annular seal member is also fixed to the casing, and these seal members are pressed against each other. According to such a configuration, as the rotary shaft rotates, the rotary shaft side seal member and the casing side seal member slide, and the sliding surface functions as a seal surface. The gap between the casing is sealed.

  FIG. 8 is a schematic longitudinal sectional view showing a rotary shaft seal structure 70 according to a conventional example employing a mechanical seal (see FIG. 3 of Patent Document 1). The seal structure 70 includes a chamber side plate 71, a blade rotation shaft 72 provided through the chamber side plate 71, an annular wear-resistant alloy 73 fitted and fixed to the blade rotation shaft 72, and a chamber side plate A guide metal 75 fixed to 71 with a fixing bolt 74, a cylindrical member having a collar 76 at one end and fitted inside the guide metal 75, and attached to the tip of the packing retainer 77 Packing 78, a stud bolt 79 penetrating the flange 76 of the packing presser 77 and having its tip fixed to the guide metal 75, a pressing force adjusting nut 80 screwed into the stud bolt 79, and a packing A spring 81 interposed between the flange portion 76 of the presser 77 and the pressing force adjusting nut 80 is provided. According to this seal structure 70, the packing retainer 77 receives an urging force from the spring 81, so that the packing 78 attached to the tip of the packing retainer 77 is pressed against the wear resistant alloy 73, and the packing 78 and the wear resistance. The inside and outside of the chamber side plate 71 are isolated from each other by the sliding surface 82 with the alloy.

JP-A-11-287328

  However, according to the conventional seal structure 70 of the rotating shaft, the packing retainer 77 is cylindrical as described above and has a certain length in the axial direction of the blade rotating shaft 72. There is a problem that it is difficult to work. More specifically, in the seal structure 70 of the rotating shaft, the packing 78 wears with time, so the degree of wear of the packing 78 is periodically checked, and if the wear is advanced, a new packing is used. The maintenance work of replacing with 78 is necessary. Here, the packing 78 is inspected or replaced by loosening the pressing force adjusting nut 80 shown in FIG. 8 and sliding the packing presser 77 along the stud bolt 79 to pull it out from the guide metal 75 and attach it to the tip. This is done by exposing the packing 78. Therefore, considering the ease with which the packing 78 can be inspected or replaced, it is preferable to secure a sufficient length of the stud bolt 79 so that the packing presser 77 can be slid as far as possible from the guide metal 75. It is. However, although not shown in FIG. 8, for example, a member such as a bearing for rotatably supporting the blade rotation shaft 72 is provided at a position outside the stud bolt 79. May not be sufficient. In this case, even if the packing presser 77 is fully slid along the stud bolt 79 and pulled out from the guide metal 75, the packing 78 at the tip thereof is in a position close to the guide metal 75, so that it is difficult to perform inspection or replacement work.

  Further, according to the conventional rotary shaft seal structure 70, since the number of parts of the members constituting the seal structure 70 is large, there is a problem that the cost is increased and the maintenance work is complicated.

  The present invention has been made in view of such problems, and provides a seal structure for a rotary shaft that has a small number of parts and is easy to maintain at a location where the rotary shaft that is rotationally driven penetrates the casing.

  In order to achieve the above object, a rotary shaft seal structure according to the present invention comprises a casing having a container therein, a rotary shaft provided through the casing and driven to rotate, and a peripheral surface of the rotary shaft. An annular rotation-side sliding body provided in a radially projecting manner at a position inside the casing, and a cylindrical member surrounding the rotation shaft via a predetermined gap, A fixed-side sliding body whose surface is in contact with the casing and whose inner end surface is in contact with the rotating-side sliding body, a pressing plate that is a flat plate member fixed to the outer end surface of the fixed-side sliding body, and the pressing plate A fixing bolt whose tip is fixed to the casing, a pressing force adjusting nut screwed into a position outside the pressing plate of the fixing bolt, the pressing force adjusting nut and the pressing plate, Intervened between A biasing spring for biasing the pressing plate in the casing, in which and a bearing unit for rotatably supporting the rotary shaft is provided on the outer side than the fixing bolts.

  The seal structure of the rotating shaft according to the present invention is such that the fixed-side sliding body is divided into a plurality of parts in the circumferential direction.

  In the seal structure of the rotating shaft according to the present invention, the fixed-side sliding body is divided into two in the circumferential direction, and a convex portion is formed on one of the divided pieces, and the convex portion is formed on the other divided piece. A recess to be fitted is formed.

  According to the seal structure of the rotating shaft according to the present invention, the pressing plate for pressing the fixed-side sliding body is a flat plate member, and the length in the axial direction of the rotating shaft is short, so that maintenance work is easy to perform. There are advantages. That is, by providing the bearing unit at a position outside the fixing bolt, even if the fixing bolt cannot be secured sufficiently long, the entire length of the fixed sliding body is sufficiently separated from the casing because the pressing plate is short. Therefore, it is easy to inspect and replace the fixed-side sliding body. Furthermore, according to the seal structure of the rotating shaft according to the present invention, since the tip end portion of the fixing bolt is directly fixed to the casing, the number of parts can be reduced, and the cost can be reduced and the maintenance work can be facilitated. There is an advantage that you can.

  Further, according to the seal structure of the rotating shaft according to the present invention, the fixed-side sliding body is divided into a plurality of parts in the circumferential direction, so that only the fixed-side sliding body can be removed and replaced with a new one without removing the bearing unit. Can do. Thereby, the effort which a maintenance operation requires can be saved.

  Further, according to the seal structure of the rotating shaft according to the present invention, the fixed-side sliding body is divided into two in the circumferential direction, and a convex portion is formed on one of the divided pieces, and a concave portion is formed on the other divided piece. By doing so, it is possible to prevent the contents inside the casing from leaking outside from the split surface of the stationary sliding body.

  First, a seal structure for a rotating shaft according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic longitudinal cross-sectional view showing a main configuration of a mixer 1 having a rotary shaft sealing structure according to the present embodiment. The mixer 1 accommodates a mixture (contained material) 2 therein and is provided with a mixing tank wall (casing) 4 in which a shaft insertion hole 3 is formed and a shaft insertion hole 3 formed in the mixing tank wall 4 so as to rotate. A rotating shaft 5 to be driven, a stirrer 6 fixed to the rotating shaft 5 to stir the mixture 2, and a bearing (bearing unit) that rotatably supports a portion of the rotating shaft 5 protruding outside the mixing vessel wall 4 ) 7, a bearing case (bearing unit) 8 that holds the bearing 7, a bearing housing 9 that extends laterally from the mixing vessel wall 4 and supports the bearing case 8, and insertion of the mixing vessel wall 4 And a sealing structure 11 for sealing the gap 10 between the hole and the rotary shaft 5.

  FIG. 2 is a partially enlarged vertical cross-sectional view in which the seal structure 11 is enlarged in FIG. The seal structure 11 includes a rotation side seal unit 12 provided on the rotation shaft 5 and a fixed side seal unit 13 provided on the mixing tank wall 4.

  FIG. 3 is a schematic exploded perspective view showing a state where the rotary side seal unit 12 is disassembled. The rotation-side seal unit 12 includes a rotation-side sliding body 14 made of a material having excellent wear resistance such as ceramic, and an O-ring 15 made of a material such as rubber. The rotation-side sliding body 14 is a plate-like member formed in an annular shape in plan view, and has an inner diameter that is substantially equal to the outer diameter of the rotary shaft 5 and makes a round around the outer peripheral surface 16. Thus, a circumferential groove 17 is formed. As shown in FIG. 2, the rotation-side sliding body 14 configured in this manner is fitted and fixed at a position inside the mixing vessel wall 4 in the rotation shaft 5, and its outer peripheral surface 16 abuts on the stirrer 6. The outer end face 18 is slightly separated from the mixing vessel wall 4. In the present embodiment, the rotation-side sliding body 14 is configured as a separate body from the rotation shaft 5, but the rotation-side sliding body 14 may be configured integrally with the rotation shaft 5.

  On the other hand, the O-ring 15 is a ring-shaped member having a substantially circular vertical cross section, and the diameter of the vertical cross section is formed to be slightly larger than the groove depth of the circumferential groove 17 of the rotating side sliding body 14. The O-ring 15 configured as described above is mounted on the outer periphery of the rotation-side sliding body 14 so as to be accommodated in the circumferential groove 17. At this time, since the diameter of the longitudinal section of the O-ring 15 is slightly larger than the groove depth of the circumferential groove 17 as described above, the top of the O-ring 15 protrudes from the circumferential groove 17. As shown in FIG. 2, in a state where the rotating side sliding body 14 is fitted and fixed to the rotating shaft 5, the top of the O-ring 15 protruding from the circumferential groove 17 is pressure-bonded to the stirrer 6. The mixture 2 is prevented from entering the contact surface between the sliding body 14 and the stirring bar 6.

  FIG. 4 is a schematic exploded perspective view showing a state where the fixed-side seal unit 13 is disassembled. The fixed-side seal unit 13 includes a fixed-side sliding body 19 having a substantially cylindrical shape, an O-ring 21 attached to the outer peripheral surface 20 of the fixed-side sliding body 19, and mounting bolts on the outer end surface 22 of the fixed-side sliding body 19. 23, a pressing plate 24 attached via 23, a fixing bolt 25 for fixing the pressing plate 24 to the mixing tank wall 4, a pressing force adjusting nut 26 screwed to the fixing bolt 25, and the pressing force adjustment. A biasing spring 27 interposed between the nut 26 and the pressing plate 24 is provided.

  The fixed-side sliding body 19 is a member made of a material that is inferior in wear resistance to the rotating-side sliding body 14 but has excellent sliding properties, for example, engineering plastic. As shown in FIG. 4, the fixed-side sliding body 19 is composed of a first divided piece 28 and a second divided piece 29 by being divided into two in the circumferential direction. And the recessed part 30 is formed in the division surface of the 1st division piece 28, respectively, On the division surface of the 2nd division piece 29, the convex part 31 of the shape fitted to the depression 30 of the 1st division piece 28 is formed. Each is formed. The fixed-side sliding body 19 configured as described above has an inner diameter larger than the diameter of the rotary shaft 5 and an outer diameter substantially the same as the shaft insertion hole 3 of the mixing vessel wall 4 shown in FIG. ing. Further, as shown in FIG. 4, a total of four screw holes 32 for screwing the mounting bolts 23 are formed in one outer end surface 22 of the fixed-side sliding body 19. Further, a circumferential groove 33 for mounting the O-ring 21 is formed on the outer peripheral surface 20 of the fixed-side sliding body 19. Further, the inner peripheral surface 34 of the fixed-side sliding body 19 is formed such that the end opposite to the side on which the pressing plate 24 is attached is gradually increased in diameter, so that the inner end surface 35, that is, the rotating-side sliding body. The end surface on the side pressed against the outer surface 14 is thinner than the outer end surface 22. As a result, the contact area between the fixed-side sliding body 19 and the rotating-side sliding body 14 is reduced, and the fixed-side sliding body 19 can be pressed against the rotating-side sliding body 14 with a uniform contact pressure in the radial direction. As shown in FIG. 2, the fixed-side sliding body 19 configured as described above is disposed so as to surround the rotary shaft 5 via the gap 36, and the outer peripheral surface 20 abuts on the mixing vessel wall 4, The inner end face 35 abuts on the rotation side sliding body 14.

  In addition, if the longitudinal cross-sectional shape of the recessed part 30 and the convex part 31 is a shape which can mutually be fitted, it is not restricted to a present Example, A design change is possible suitably. Contrary to the present embodiment, the convex portion 31 may be formed on the first divided piece 28 and the concave portion 30 may be formed on the second divided piece 29. Further, the number of divisions of the fixed-side sliding body 19 is not limited to two divisions, and can be divided into, for example, three divisions or four divisions.

  The O-ring 21 is a ring-shaped member having a substantially circular longitudinal section made of a material such as rubber, and the diameter of the longitudinal section is formed to be slightly larger than the groove depth of the circumferential groove 33 of the fixed-side sliding body 19. . The O-ring 21 configured as described above is mounted on the outer periphery of the fixed-side sliding body 19 so as to be accommodated in the circumferential groove 33. At this time, since the diameter of the vertical section of the O-ring 21 is slightly larger than the groove depth of the circumferential groove 33 as described above, the top of the O-ring 21 protrudes from the circumferential groove 33. As shown in FIG. 2, in a state where the fixed-side sliding body 19 is fitted in the shaft insertion hole 3 of the mixing tank wall 4, the top of the O-ring 21 protruding from the circumferential groove 33 is crimped to the mixing tank wall 4. By doing so, the mixture 2 is prevented from entering the contact surface between the stationary sliding body 19 and the mixing vessel wall 4.

  The pressing plate 24 plays a role of integrating the fixed side sliding body 19 divided into two parts and a role of pressing the integrated fixed side sliding body 19. As shown in FIG. 4, the pressing plate 24 is a flat plate member having a substantially annular shape in plan view, and has an inner diameter that is substantially equal to the inner diameter of the fixed-side sliding body 19. The pressing plate 24 is formed with a total of four mounting bolt insertion holes 37 through which the mounting bolts 23 are inserted so as to correspond to the four screw holes 32 of the fixed-side sliding body 19. Further, a total of four fixing bolt insertion holes 38 for inserting the fixing bolts 25 are formed at positions outside the mounting bolt insertion holes 37. The pressing plate 24 configured in this way is screwed into the screw holes 32 of the fixed-side sliding body 19 with the mounting bolts 23 through which the respective mounting bolt insertion holes 37 are inserted, so that the outer end face 22 of the fixed-side sliding body 19. Fixed to.

  As shown in FIG. 4, the fixing bolt 25 is a bolt without a head composed of only a long shaft portion. This fixing bolt 25 is inserted through the fixing bolt insertion hole 38 of the pressing plate 24 and, as shown in FIG. 2, the tip portion thereof is screwed into the fixing nut 39 fixed to the mixing vessel wall 4. Fixed to the mixing vessel wall 4. Although not shown in detail in FIG. 2, an insertion hole into which the tip of the fixing bolt 25 is inserted is formed at the position where the fixing nut 39 is fixed on the mixing tank wall 4. The pressing force adjusting nut 26 is for adjusting the magnitude of the pressing force that presses the fixed-side sliding body 19 against the rotating-side sliding body 14. As shown in FIG. 2, the pressing force adjusting nut 26 is screwed into a position outside the pressing plate 24 in the fixing bolt 25, and is moved along the fixing bolt 25 by turning in the tightening direction or the loosening direction. Can do.

  The biasing spring 27 is a so-called coil spring. As shown in FIG. 2, the urging spring 27 is disposed in a compressed state between the pressing force adjusting nut 26 and the pressing plate 24 so as to be wound around the fixing bolt 25. When the pressing plate 24 is biased by the biasing spring 27, the fixed-side sliding body 19 integrated with the pressing plate 24 is pressed against the rotating-side sliding body 14 with a predetermined pressing force. Then, when the pressing force adjusting nut 26 is rotated and moved along the fixing bolt 25, the biasing spring 27 is compressed or extended between the pressing force adjusting nut 26 and the pressing plate 24. By adjusting the urging force, the magnitude of the pressing force for pressing the stationary sliding body 19 against the rotating sliding body 14 can be adjusted.

  According to the seal structure 11 of the rotating shaft 5 configured as described above, when the rotating shaft 5 rotates, the rotating side sliding body 14 rotates along with this, whereby the rotating side sliding body 14 and the fixed side sliding body. 19 slides. And since this sliding surface functions as a sealing surface, it is prevented that the mixture 2 inside the mixing tank wall 4 leaks outside. In addition, according to the seal structure 11, as shown in FIG. 2, the gap 36 between the rotary shaft 5 and the fixed-side sliding body 19 is located outside the seal surface, so that the mixture 2 enters the gap 36. Absent. Therefore, the problem of contaminating the inside of the mixing vessel wall 4 due to the mixture 2 remaining in the gap 36 flowing backward does not occur.

  Next, the maintenance work of the seal structure 11 of the rotating shaft 5 according to the present embodiment will be described. As described above, since the rotating side sliding body 14 is made of a material having higher wear resistance than the fixed side sliding body 19, the sliding side sliding body 19 is worn by sliding of both. Accordingly, it is necessary to perform a maintenance work of periodically inspecting the degree of wear of the fixed-side sliding body 19 and replacing it with a new one when the wear has progressed. When performing such maintenance work, the user first inserts his hand under the bearing housing 9 from the state shown in FIG. 2 and rotates the pressing force adjusting nut 26 in the loosening direction to move the pressing force adjusting nut 26. It moves along the fixing bolt 25 in the direction away from the pressing plate 24. Then, as the distance between the pressing force adjusting nut 26 and the pressing plate 24 increases, the urging spring 27 interposed therebetween is gradually extended, and the urging force exerted on the pressing plate 24 by the urging spring 27 gradually increases. Becomes smaller. Then, as shown in FIG. 5, when the length of the biasing spring 27 reaches the natural length, the magnitude of the biasing force that the biasing spring 27 exerts on the pressing plate 24 becomes zero.

  Next, the user moves the pressing plate 24 along the fixing bolt 25 in the direction of approaching the pressing force adjusting nut 26 from the state shown in FIG. Then, as the distance between the pressing force adjusting nut 26 and the pressing plate 24 becomes narrower, the urging spring 27 interposed therebetween is gradually compressed, and the urging force exerted on the pressing plate 24 by the urging spring 27 is increased. Gradually grows. The user further moves the pressing plate 24 in the direction of the pressing force adjusting nut 26 against this biasing force, and as shown in FIG. 6, the fixed-side sliding body 19 integrated with the pressing plate 24 is inserted into the shaft insertion hole. 3 to the outside. And the inner side end surface 35 of the fixed side sliding body 19 is inspected, and the wear degree is confirmed.

  When it is determined that the fixed-side sliding body 19 needs to be replaced with a new one, the user loosens the four mounting bolts 23 from the state shown in FIG. 6 to fix the pressing plate 24 and the fixed-side sliding body 19. Is released. If it does so, the 1st division piece 28 and the 2nd division piece 29 which comprise the fixed side sliding body 19 will be in a state which can be mutually isolate | separated by removing the press plate 24 which was playing the role of integration. Thereby, the user removes only the fixed side sliding body 19 from the periphery of the rotary shaft 5 as shown in FIG. 7 by separating the fixed side sliding body 19 into the first divided piece 28 and the second divided piece 29. Can do.

  Thereafter, although not shown in detail in the drawing, the user separates the prepared new fixed-side sliding body 19 into the first divided piece 28 and the second divided piece 29 and sandwiches the rotary shaft 5 so as to sandwich the first divided piece 28. The fixed-side sliding body 19 is integrated at a position between the pressing plate 24 and the mixing vessel wall 4 by fitting the concave portion 30 and the convex portion 31 of the second divided piece 29 to each other. Then, the integrated fixed-side sliding body 19 is fixed to the pressing plate 24 using the mounting bolt 23. Next, the user moves the pressing plate 24 along the fixing bolt 25 in a direction away from the pressing force adjusting nut 26, and inserts the fixed-side sliding body 19 integrated with the pressing plate 24 into the shaft insertion hole 3. The end face is brought into contact with the rotation-side sliding body 14. Finally, the user moves the pressing force adjusting nut 26 in the tightening direction so as to move along the fixing bolt 25 in the direction approaching the pressing plate 24. Then, as shown in FIG. 2, as the distance between the pressing force adjusting nut 26 and the pressing plate 24 becomes narrower, the biasing spring 27 interposed therebetween is gradually compressed, and the biasing spring 27 is pressed. The urging force exerted on the plate 24 gradually increases. Then, the fixed-side sliding body 19 integrated with the pressing plate 24 is pressed against the rotation-side sliding body 14 by this urging force. Thereby, the maintenance work is completed.

  According to the maintenance work as described above, the fixed-side sliding body 19 to be replaced is divided into two parts, so that it can be fixed without removing the members such as the bearing 7, the bearing case 8, and the rotating shaft 5 shown in FIG. Since only the side sliding body 19 can be removed and replaced with a new one, the labor required for maintenance work can be saved. Moreover, since the recessed part 30 and the convex part 31 which mutually fit are formed in the 1st divided piece 28 and the 2nd divided piece 29 which comprise the stationary-side sliding body 19, respectively, it accommodates in the inside of the mixing tank wall 4. It is possible to prevent the mixture 2 thus leaked from the split surface of the stationary-side sliding body 19 to the outside.

  Further, as shown in FIG. 2, the pressing plate 24 for pressing the fixed-side sliding body 19 is a flat plate member, and the length of the rotating shaft 5 in the axial direction is very short, so that maintenance work can be easily performed. There is an advantage. That is, as shown in FIG. 1, the length of the fixing bolt 25 may not be sufficiently secured due to circumstances such as the provision of members such as the bearing 7 and the bearing case 8 at positions outside the fixing bolt 25. Even in this case, since the entire length of the pressing plate 24 is short, the entire stationary slide 19 can be moved to a position sufficiently away from the mixing vessel wall 4, so that the inspection and replacement of the stationary slide 19 can be performed. Easy to do. Further, as shown in FIG. 2, since the tip of the fixing bolt 25 is directly fixed to the mixing vessel wall 4, compared to the conventional example shown in FIG. 8, the guide metal 75 and the fixing bolt to which the stud bolt 79 is fixed. 74 is unnecessary, and the number of parts can be reduced. Thereby, there is an advantage that cost reduction and easy maintenance work can be achieved.

  The seal structure of the rotating shaft according to the present invention is not limited to a mixer, and can be applied to any device that has a rotating shaft provided through a casing.

The schematic longitudinal cross-sectional view which shows the principal part structure of the mixer 1 provided with the sealing structure 11 of the rotating shaft which concerns on the Example of this invention. The partial expanded longitudinal cross-sectional view which expanded the seal structure 11 in FIG. The schematic exploded perspective view which shows the state which decomposed | disassembled the rotation side seal unit 12. FIG. FIG. 4 is a schematic exploded perspective view showing a state where a fixed side seal unit 13 is disassembled. It is a figure for demonstrating the maintenance operation | work of the sealing structure 11 of the rotating shaft which concerns on a present Example, Comprising: The partial expanded longitudinal cross-sectional view which expanded the sealing structure 11 in FIG. It is a figure for demonstrating the maintenance operation | work of the sealing structure 11 of the rotating shaft which concerns on a present Example, Comprising: The partial expanded longitudinal cross-sectional view which expanded the sealing structure 11 in FIG. It is a figure for demonstrating the maintenance operation | work of the sealing structure 11 of the rotating shaft which concerns on a present Example, Comprising: The partial expanded longitudinal cross-sectional view which expanded the sealing structure 11 in FIG. The schematic longitudinal cross-sectional view which shows the sealing structure 70 of the rotating shaft which concerns on a prior art example.

Explanation of symbols

2 Mixture (containment)
4 Mixing tank wall (casing)
5 Rotating shaft 7 Bearing (bearing unit)
8 Bearing case (bearing unit)
11 Rotating shaft sealing structure 14 Rotating side sliding body 19 Fixed side sliding body 20 Outer peripheral surface (fixed side sliding body)
22 Outer end face (fixed side sliding body)
24 pressing plate 25 fixing bolt 26 pressing force adjusting nut 27 biasing spring 28 first divided piece 29 second divided piece 30 concave portion 31 convex portion 35 inner end face (fixed side sliding body)
36 Clearance

Claims (3)

A casing having contents inside,
A rotating shaft provided through the casing and driven to rotate;
An annular-shaped rotation-side sliding body provided on the circumferential surface of the rotating shaft and projecting in the radial direction at a position inside the casing;
A cylindrical member that surrounds the rotating shaft via a predetermined gap, an outer peripheral surface of which is in contact with the casing, and an inner end surface of which is in contact with the rotating side sliding member;
A pressing plate which is a flat plate member fixed to the outer end face of the fixed-side sliding body;
A fixing bolt inserted through the pressing plate and having its tip fixed to the casing;
A pressing force adjusting nut screwed into a position outside the pressing plate of the fixing bolt;
A biasing spring that is interposed between the pressing force adjusting nut and the pressing plate and biases the pressing plate toward the casing;
A bearing unit provided outside the fixing bolt and rotatably supporting the rotating shaft;
A rotary shaft seal structure comprising:   The rotary shaft seal structure according to claim 1, wherein the fixed-side sliding body is divided into a plurality of parts in the circumferential direction.   The fixed-side sliding body is divided into two in the circumferential direction, and a convex portion is formed on one of the divided pieces, and a concave portion that fits the convex portion is formed on the other divided piece. The seal structure of the rotating shaft according to claim 2.

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