JPH051739Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shaft seal structure, and particularly to a shaft seal structure in which a structure for supporting a seal member on a stuffing box is improved.

[Prior Art] It is generally known that a sealing member is fitted to a rotating shaft of a rotating device or the like. Particularly, for rotating equipment and the like that are used at low temperatures, a sealing member made of carbon, for example, is used as the sealing member. Since such a seal member is relatively heavy and its set position is lowered, the following shaft seal structure has been adopted in order to make the seal member follow the rotating shaft.

A conventional shaft seal structure a is shown in FIGS. 5, 6, and 7.

As shown in FIG. 5, a ring-shaped seal member c made of carbon, for example, is fitted onto the rotating shaft b. A stuffing box d is formed on the outer side of the seal member c so as to cover it. A resilient member f is interposed between the inner wall of the box d and one side surface e of the seal member c perpendicular to the axial direction. As shown in FIG. 6, this elastic member f is formed of a plate spring g, and is bent from the radial outer circumference h of the seal member c to the above-mentioned one side e, and from the seal member c to the box d. It is configured to generate a biasing force against the inner wall. As shown in FIG. 7, a plurality of plate springs g are provided along the circumferential direction of the seal member c. As shown in the figure, the seal member c is formed of a plurality of divided pieces i for convenience when assembling and disassembling, and by restraining the outer periphery h with a band j, it can be assembled into one piece. Fixed and formed.

In the conventional shaft seal structure a configured as described above, the plate spring g applies a biasing force to support the seal member c on the inner wall of the box d, thereby allowing the seal member c to follow the rotating shaft b. It was improving sex.

[Problems to be solved by the invention] By the way, the conventional shaft seal structure has the following problems.

Since the resilient member f is formed of a plate spring g and is bent between one side e of the seal member c and the inner wall of the box d to adjust the biasing force, its setting is empirical and the biasing force cannot be predicted. I can't do it,
In addition, since a plurality of them are provided, there is a problem that adjustment is difficult.

In addition, especially when the seal member c is formed of a plurality of divided pieces, as shown in FIG. There was a problem in that the sealing members g could not be arranged at equal intervals along the circumferential direction of the sealing member c, and the biasing force would be biased.

[Purpose of the invention] The present invention was created to solve problems in the shaft seal structure.

The purpose is to provide a shaft seal structure in which the biasing force of the seal member against the inner wall of the stuffing box can be predicted by calculated values and can be easily adjusted.

[Summary of the invention] In order to achieve the above object, the present invention includes a sealing member fitted to a rotating shaft, a stuffing box covering the sealing member being formed on the outer side of the sealing member, and an inner wall of the box and the stuffing box described above. In the shaft seal structure in which a resilient member is interposed between the seal member and the seal member to support the seal member, a recess extending in the axial direction facing the inner wall of the box is formed in the seal member, and a recess is formed in the recess. , a piston that contacts the inner wall of the box, a coil spring that biases the piston in a pressure direction, and a cassette that is removably inserted into the recess, accommodates the piston so as to be retractable, and restrains the spring in the axial direction. A seal support member is provided on the cassette and includes a claw that supports one end of the spring and releases the restraint by expanding. With this configuration, the piston is brought into pressure contact with the inner wall of the box by the biasing force of the spring, causing the seal member to follow the rotation axis. This biasing force is adjusted by extending the claw and replacing the coil spring after the cassette is removed from the recess.

[Example] Next, an example of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a shaft seal structure 1 of the present invention. As shown in the figure, a ring-shaped sealing member 3 is fitted onto the rotating shaft 2. As shown in FIG. This seal member 3 is made of carbon, for example. For convenience in assembly and disassembly, the seal member 3 is formed of a plurality of divided pieces 4, whose radial outer peripheral portions 5 are restrained by a band 6 and fixed integrally. A stuffing box 7 is formed on the outer side of the seal member 3 so as to cover it. The inner wall of the box 7 and one side surface 8 perpendicular to the axial direction of the sealing member 3 face each other, and a gap S is formed between them. Further, a recess 9 is formed in the one side 8 of the sealing member 3 facing the inner wall of the box 7. The recesses 9 are formed in a cylindrical shape, and a plurality of recesses 9 are formed at equal intervals along the circumferential direction of the seal member 3. Inside these, there is a seal support member 1 for supporting the seal member 3 on the inner wall of the box 7.
0 is provided in a removable manner. This seal support member 10 is formed as shown in FIGS. 2 and 3. As shown in the figure, the seal support member 10 includes a cylindrical cassette 11 and a coil spring 12 housed within the cassette 11.
and a piston 13 which is urged by this coil spring 12 and comes into pressure contact with the inner wall of the box 7. The piston 13 of this cassette 11
The diameter of the opening at the side end is reduced to form a stopper 14 for the piston 13. Also,
A claw 15 is formed in the opening at the other end and supports one end of the coil spring 12. This nail 1
The coil spring 12 in the cassette 11 can be replaced by bending and stretching the coil spring 5.

The operation of the shaft seal structure 1 constructed as above will be described.

As shown in FIGS. 2 and 3, a coil spring 12 having the necessary biasing force is selected and installed in the cassette 11 forming the seal support member 10. Since the spring constant of the coil spring 12 can be determined, a coil spring 12 having a biasing force predicted by a pre-calculated value is selected. The selected coil spring 12 is mounted by extending the claw 15, inserting the piston 13 into the cassette 11, inserting the coil spring 12, and bending the claw 15 again. The seal support member 10 formed in this way is attached to the seal member 3 as shown in FIG.
In each of the plurality of recesses 9 formed on one side 8 of the
Provide one by one. Then, the seal member 3 is fitted onto the rotating shaft 2. When the seal member 3 is formed of a plurality of divided pieces 4, the divided pieces 4 are restrained by the attachment band 6 so as to sandwich the rotating shaft 2 from the radial direction, and are fixed integrally. At this time, the piston 13 urged by the coil spring 12 of the seal support member 10 comes into pressure contact with the inner wall of the box 7, and the piston 13 retreats into the cassette 11 as shown by the broken line in FIG. I will do it.

In this way, in this embodiment, the biasing force of the coil spring 12 of the seal support member 10 is predicted by a calculated value, and the coil spring 12 is replaceable, so that the biasing force can be easily adjusted.

Furthermore, as shown in FIGS. 1 and 4, a recess 9 is formed in one side 8 of the seal member 3, and a seal support member 10 is provided inside the recess 9, so that the seal member 3 is separated into a plurality of divided pieces 4. Even if the shaft seal is formed with a band 6 and is restrained by a band 6,
Since they do not interfere with the arrangement of the seal support member 10, they can be arranged at equal intervals along the circumferential direction on one side 8 of the seal member 3. Therefore, the urging force on the inner wall of the box 7 is applied evenly along the circumferential direction of the seal member 3, and the ability of the seal member 3 to follow the rotation axis is improved.

Further, the seal support member 10 of the present invention is such that the piston 13 and the coil spring 12 are attached to the cassette 1 in advance.
1, the seal member 13 can be easily attached by simply inserting it into the recess 9 formed in the seal member 13, and the workability in processing and assembling the shaft seal structure can be improved.

[Effects of the invention] In summary, the present invention provides the following excellent effects.

(1) A recess extending in the axial direction facing the inner wall of the stuffing box is formed in the seal member, and a seal support member consisting of a piston, a coil spring, a cassette, and a pawl is provided in this recess.
The biasing force of the seal member against the box can be made uniform in the circumferential direction, and the desired biasing force can be accurately obtained.

(2) By replacing the coil spring by removing the cassette and extending the claw, the biasing force can be easily adjusted, and it is also easy to attach to the box, improving the workability of processing and assembling the shaft seal structure. .

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a main part showing an embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view showing a coil spring and a seal support member of the present invention, and FIG. 3 is a view taken from the - line arrow in FIG. 4 is a side view of the shaft seal structure of the present invention seen from one side in the axial direction, FIG. 5 is a vertical cross-sectional view of the conventional shaft seal structure, and FIG. 6 is a vertical cross-section showing the main parts of FIG. 7 are side views of a conventional shaft seal structure viewed from one side in the axial direction. In the figure, 1 is a shaft seal structure, 2 is a rotating shaft, 3 is a seal member, 7 is a stuffing box, 9 is a recess, 10 is a seal support member, 11 is a cassette, 1
2 is a coil spring, 13 is a piston, and 15 is a claw.

Claims (1)

[Scope of utility model registration request] A sealing member is fitted to the rotating shaft, and a stuffing box is formed on the outer side of the sealing member to cover the stuffing box, and a resilient member is interposed between the inner wall of the box and the sealing member to tighten the sealing member. In the shaft seal structure for supporting the member, a recess extending in the axial direction facing the inner wall of the box is formed in the seal member, and a piston that abuts the inner wall of the box is placed in the recess, and the piston is pressed in a pressing direction. a coil spring that biases the piston; a cassette that is removably inserted into the recess, accommodates the piston in a retractable manner, and restrains the spring in the axial direction; and a cassette that is formed in the cassette and supports one end of the spring. A shaft seal structure characterized in that a seal support member is provided, comprising a claw that releases the restraint by expanding and releasing the restraint.