JP7365757B2 - Seal structure of rotating machines and rotating machines - Google Patents

Description

The present invention relates to a seal structure for a rotating machine including a case and a shaft member arranged in the case so as to be rotatable relative to the case, a rotating machine having the seal structure, and a seal member used in the seal structure. .

In a rotating machine such as a reducer that includes a case and a shaft member disposed within the case, for example, in order to prevent internal lubricating oil from leaking, the gap between the case and the shaft member is sealed with a seal member. There is. Such a seal structure constructed between the case and the shaft member generally reduces the gap between the case and the shaft member by bringing a lip provided on the annular seal member into contact with the case or the shaft member. Seal. In the field of this type of seal structure, many various techniques have been proposed in the past, and for example, Patent Documents 1 to 4 disclose techniques related to lip shapes and the like.

Japanese Patent Application Publication No. 2016-138654 Japanese Patent Application Publication No. 2002-228009 Japanese Patent Application Publication No. 2004-239377 Patent No. 4953848

In the seal structure as described above, it is desired that the seal member be made smaller, simpler, and easier to assemble while ensuring appropriate sealing performance. In addition, sealing members increase the frictional resistance between the case and the shaft member and reduce the mechanical efficiency of rotating machinery, so it is not possible to suppress the decline in mechanical efficiency while ensuring appropriate sealing performance. It is useful if

The present invention has been made in consideration of the above-mentioned circumstances, and it is possible to achieve downsizing, simplification, and improvement in assembly of a sealing member while ensuring appropriate sealing performance, and to improve the mechanical efficiency of rotating machinery. It is an object of the present invention to provide a seal structure for a rotating machine, a rotating machine, and a seal member that can also improve the performance.

The present invention provides a rotating machine including a case and a shaft member disposed in the case so as to be rotatable relative to the case, from which a lubricating oil storage space located between the case and the shaft member is provided. A sealing structure for preventing leakage of lubricating oil, the sealing structure including a sealing member sealing a gap formed between the case and the shaft member, and connected to one of the case and the shaft member. A seal forming portion (extending portion) located between the case and the shaft member is provided, and the seal member is provided on the other of the case and the shaft member and is larger than the seal forming portion. The sealing member is connected to an annular support portion that is disposed on an outer side separated from the lubricating oil storage space in the axial direction, and faces the seal forming portion from the outer side in the axial direction; This is a seal structure for a rotating machine, comprising a lip (main lip) that forms the seal with a seal forming part.

In the seal structure for a rotating machine according to the present invention, the lip extends from the annular support portion located on the outside of the seal forming portion (extending portion) in the axial direction toward the seal forming portion, and extends toward the seal forming portion in the axial direction. By making contact (directly or indirectly) and thereby creating a seal, the restriction on the dimensional freedom of the lip in the radial direction imposed by the support part is relaxed, so the radial dimension of the lip can be secured large. It becomes easier. As a result, by enlarging only the lip, it is possible to ensure strong sealing performance without strongly pressing the lip against the seal forming portion, and it is possible to downsize and simplify the entire sealing member. Further, by suppressing the pressing force of the lip against the seal forming portion while ensuring strong sealing performance, it is possible to improve the mechanical efficiency of the rotating machine by suppressing frictional resistance. In addition, since the seal member is provided so as to be located outside the seal forming part in the axial direction, it is easier to avoid undesired interference between the seal member and the seal forming part, etc. during assembly, and damage to the seal member may occur. It is also possible to suppress the Therefore, while ensuring appropriate sealing performance, it is possible to reduce the size and simplicity of the seal member, and improve assembly efficiency, and it is also possible to improve the mechanical efficiency of the rotating machine.

Further, in the seal structure of the present invention, the lip is inclined with respect to the axial direction and the radial direction, and is located on the outer side in the axial direction and on the one side of the case and the shaft member in the radial direction. and may be located on a side opposite to the outside in the axial direction and on the other side of the case and the shaft member in the radial direction.

In this case, when fluid such as lubricating oil flows from the seal forming part side to the seal member side, the lip is pressed against the seal forming part, and the adhesion of the lip to the seal forming part increases. Thereby, sealing performance can be effectively improved at the timing when sealing is required.

Further, in the seal structure of the present invention, the lip may be connected to an end of the support portion that is on one side of the case and the shaft member.

In this case, it becomes easy to ensure a large radial dimension of the lip, and it is possible to bring the lip and the seal forming portion into contact while suppressing the radial dimension of the seal forming portion. This makes it easier to downsize and simplify the seal member, and it also becomes possible to downsize and simplify the seal forming section.

Further, in the seal structure of the present invention, the angle that the lip makes with the axial direction may be 44.5 degrees or more and 45.5 degrees or less.

In this case, the lip is inclined at approximately 45 degrees to the axial direction. This prevents the lip from excessively deforming in the axial direction when it comes into contact with the seal forming part, and also prevents fluid such as lubricating oil from flowing from the seal forming part side to the sealing member side. The lip is brought into close contact with the seal forming part. Therefore, good sealing performance can be ensured while effectively suppressing frictional resistance.

Further, in the seal structure of the present invention, the sealing member has a cylindrical portion that is fitted into the inner circumferential surface of the case or the outer circumferential surface of the shaft member, and the supporting portion is arranged in the axial direction of the cylindrical portion. Connected to the outer end, the cylindrical portion may have an axial dimension smaller than a radial dimension of the support portion.

As described above, in the seal structure of the present invention, the seal member as a whole can be downsized and simplified by ensuring strong sealing performance by increasing the size of the lip, but specifically, by increasing the size of the lip, While ensuring strong sealing performance, as in the above configuration, the axial dimension of the cylindrical part (axial dimension), which does not need to be excessively large to ensure lip sealing performance, is By making the size smaller than the size in the radial direction (radial direction dimension), the size in the axial direction of the sealing member can be suppressed while ensuring appropriate sealing performance.

In the seal structure of the present invention, the lip may have a garter springless structure that forms the seal with the seal forming portion by elastic deformation of the lip.

Similarly to the above, in the seal structure of the present invention, by increasing the size of the lip to ensure strong sealing performance, it is possible to downsize and simplify the entire seal member, but specifically, by increasing the size of the lip, While ensuring strong sealing performance, as in the above configuration, by not using the lip pressing wire (garter spring) used in general sealing members, it is possible to ensure proper sealing performance and seal. The members can be made extremely simple. Furthermore, with this configuration, it is possible to significantly suppress frictional resistance, thereby greatly improving the mechanical efficiency of the rotating machine.

Moreover, in the seal structure of the present invention, the seal forming portion may be separate from the one of the case and the shaft member.

In this case, the seal structure can be simply configured.

Moreover, in the seal structure of the present invention, the seal forming portion may be integrated with the one of the case and the shaft member.

In this case, an increase in the number of parts can be suppressed.

Further, in the seal structure of the present invention, the seal forming portion is provided between the case and the shaft member, and is an outer race of the bearing that extends in the radial direction from the inner peripheral surface of the case or the outer peripheral surface of the shaft member. Or it may be an inner lace.

In this case, since the bearing also serves as the seal forming part, an increase in the number of parts can be suppressed. Furthermore, since the outer race or inner race of a bearing generally has a smooth surface, it is possible to obtain high sealing performance when the lip contacts the outer race or inner race, while reducing processing costs. .

Moreover, in the seal structure of the present invention, the seal forming portion may be provided on the shaft member, and the seal member may be provided on the case.

Further, the present invention is a rotating machine having the above-described rotary machine seal structure.

Moreover, the present invention is provided in a rotating machine including a case and a shaft member disposed in the case so as to be rotatable relative to the case, and the shaft member is formed between the case and the shaft member. A sealing member for sealing a gap (lubricating oil storage space), the sealing member being provided on either the case or the shaft member, and comprising an annular support portion located between the case and the shaft member; a lip connected to a support part, the lip is inclined with respect to the axial direction and the radial direction, and the seal member in the radial direction is provided on a side close to the support part in the axial direction. Which one of the case and the shaft member is provided with the seal member on a side opposite to either the case and the shaft member and spaced apart from the support portion in the axial direction. A sealing member is located on that side.

The seal member according to the present invention has a lip attached to the outer side in the axial direction (shaft The gap between the case and the shaft member can be sealed by making contact from the side away from the gap in the direction of the case. This sealing state is formed by the lip extending from the annular support located on the axially outer side of the aforementioned other member toward the other member and contacting this in the axial direction; Since the restriction on the degree of freedom of dimension of the lip in the radial direction exerted by the support portion is relaxed, it becomes easier to ensure a large dimension of the lip in the radial direction. As a result, by enlarging only the lip, it is possible to ensure strong sealing performance without strongly pressing the lip against other members, and it is possible to downsize and simplify the entire sealing member. In addition, by suppressing the pressing force of the lip against other members while ensuring strong sealing performance, it is possible to improve the mechanical efficiency of the rotating machine by suppressing frictional resistance. Furthermore, since the seal member can be provided outside other members in the axial direction, it is easier to avoid undesired interference between the seal member and other members during assembly, resulting in damage to the seal member. It is also possible to suppress this. Therefore, while ensuring appropriate sealing performance, it is possible to reduce the size and simplicity of the seal member, and improve assembly efficiency, and it is also possible to improve the mechanical efficiency of the rotating machine.
Furthermore, the lip is inclined with respect to the axial direction and the radial direction so that as it moves away from the support part, it extends toward either side of the case and the shaft member where the support part (sealing member) is provided. . With this configuration, when fluid such as lubricating oil flows from the above-mentioned other member side to the sealing member side, the lip is pressed against the other member, and the adhesion of the lip to the other member is increased. Thereby, sealing performance can be effectively improved at the timing when sealing is required.

Further, the lip may be connected to an end of the support portion on a side opposite to one of the case and the shaft member where the support portion (sealing member) is provided.

In this case, it becomes easy to ensure a large radial dimension of the lip, and it becomes possible to bring the lip into contact with the other members while suppressing the radial dimensions of the other members mentioned above. This makes it easier to downsize and simplify the sealing member, and it also becomes possible to downsize and simplify other members.

Moreover, in the sealing member of the present invention, the angle that the lip makes with the axial direction may be 44.5 degrees or more and 45.5 degrees or less.

In this case, the lip is inclined at approximately 45 degrees to the axial direction. This prevents excessive deformation of the lip in the axial direction when it comes into contact with the other member mentioned above, and also prevents fluid such as lubricating oil from flowing from the side of the other member to the side of the sealing member. In some cases, the lip is brought into close contact with other members. Therefore, good sealing performance can be ensured while effectively suppressing frictional resistance.

The sealing member of the present invention further includes a cylindrical portion that is fitted into the inner circumferential surface of the case or the outer circumferential surface of the shaft member, and the supporting portion has an end opposite to a side to which the lip is connected. The cylindrical portion may have an axial dimension smaller than a radial dimension of the support portion.

As described above, in the seal member of the present invention, the seal member as a whole can be downsized and simplified by ensuring strong sealing performance by increasing the size of the lip. While ensuring strong sealing performance, as in the above configuration, the axial dimension of the cylindrical part that does not need to be made excessively large to ensure lip sealing performance is determined by the radial dimension of the support part. By making the size smaller than that, it is possible to suppress the size of the seal member in the axial direction while ensuring appropriate sealing performance.

Further, in the sealing member of the present invention, the lip may have a garter springless structure that forms a seal with another member by elastic deformation of the lip.

Similarly to the above, in the seal member of the present invention, the seal member as a whole can be downsized and simplified by ensuring strong sealing performance by increasing the size of the lip, but specifically, by increasing the size of the lip, While ensuring strong sealing performance, as in the above configuration, by not using an elastic wire (garter spring), it is possible to make the sealing member extremely simple while ensuring appropriate sealing performance. can. Furthermore, with this configuration, it is possible to significantly suppress frictional resistance, thereby greatly improving the mechanical efficiency of the rotating machine.

According to the present invention, it is possible to achieve downsizing, simplification, and improved assembly of the sealing member while ensuring appropriate sealing performance, and it is also possible to improve the mechanical efficiency of a rotating machine.

1 is a sectional view of a rotating machine to which a seal structure according to a first embodiment of the present invention is applied. FIG. 2 is an enlarged sectional view of the seal member shown in FIG. 1. FIG. FIG. 2 is a sectional view of a main part of a rotating machine to which a seal structure according to a second embodiment of the present invention is applied. FIG. 7 is a sectional view of a main part of a rotating machine to which a seal structure according to a third embodiment of the present invention is applied. It is a sectional view of the principal part of the rotary machine to which the seal structure concerning the 4th embodiment of the present invention is applied.

Embodiments of the present invention will be described below with reference to the drawings.

<First embodiment>
FIG. 1 is a sectional view of a rotating machine 1 to which a seal structure according to a first embodiment of the present invention is applied. A rotating machine 1 shown in FIG. 1 includes a case 2 and a shaft member 3 disposed within the case 2 so as to be rotatable relative to the case 2. A plurality of rolling elements 4 arranged at intervals in the circumferential direction are interposed between the inner peripheral surface of the case 2 and the outer peripheral surface of the shaft member 3 on one side and the other side in the axial direction. This allows the shaft member 3 to rotate relative to the case 2.

In the illustrated example, an inner ring raceway surface 4A on which the rolling elements 4 roll is formed by the outer peripheral surface of the shaft member 3, and an outer ring raceway surface 4B is formed by an outer race 41B fitted into the inner peripheral surface of the case 2. . Such a rotating machine 1 may be, for example, a speed reducer, more specifically an eccentric swing type speed reducer. In this case, the shaft member 3 corresponds to a carrier, and the case 2 is a cylinder that covers the outer periphery of the carrier. It corresponds to the case of In addition, the code|symbol L1 in a figure shows the central axis of the shaft member 3, and also corresponds to the rotational axis of the shaft member 3 in the illustrated example. The axial direction means a direction along the central axis L1. Furthermore, in the following description, the radial direction means a direction perpendicular to the central axis L1.

As shown in FIG. 1, in this embodiment, the shaft member 3 is provided with an annular seal forming part (extending part) 10 that extends in the radial direction toward the case 2. In this example, the seal forming part 10 is It is formed from the same material as the shaft member 3 and is integrated with the shaft member 3. A gap is formed between the radially outer end of the seal forming portion 10 and the inner peripheral surface of the case 2. On the other hand, a seal member 20 is removably provided in the case 2, and the seal member 20 is assembled so as to be located outside the seal forming portion 10 in the axial direction. The seal forming portion 10 and the seal member 20 are in contact with each other to seal the gap between the case 2 and the shaft member 3. This completes the seal structure according to this embodiment. A lubricating oil storage space S in which lubricating oil is stored is defined by the seal of the seal structure. The lubricating oil storage space S is formed between the case 2 and the shaft member 3. Note that the "outside" in the axial direction refers to the side that is spaced apart from the lubricating oil storage space S in the axial direction.

As shown in the enlarged cross-sectional view of the seal member 20 in FIG. It has a main lip (lip) 24 that extends toward the seal forming portion 10 and contacts the seal forming portion 10 in the axial direction. The main lip 24 is provided mainly for the purpose of preventing the lubricating oil inside the rotating machine 1 from leaking out of the lubricating oil storage space S, and is connected to the case 2 and the shaft by contacting the seal forming part 10 in the axial direction. The gap between the member 3 and the member 3 is sealed.

The base portion 21 includes an annular core metal 21A having an L-shape in cross section along the radial direction, and a covering body 21B made of rubber or the like that covers the entire surface of the core metal 21A. The base portion 21 includes the above-mentioned support portion 22 and a cylindrical portion 23 that is fitted into the inner circumferential surface of the case 2. Extends in the radial direction. The support portion 22 is formed by a radially extending portion of the core metal 21A and the covering body 21B, and the cylindrical portion 23 is formed by an axially extending portion of the core metal 21A and the covering body 21B. As is clear from FIG. 2, in this embodiment, the axial dimension (axial dimension) of the cylindrical portion 23 is smaller than the radial dimension (radial dimension) of the support portion 22.

The seal member 20 is held in the case 2 by deforming the cylindrical part 23 of the base part 21 radially inward and fitting it into the inner peripheral surface of the case 2. When the cylindrical portion 23 is deformed inward in the radial direction, the core bar 21A in the cylindrical portion 23 tries to elastically return to the outside in the radial direction, so that the cylindrical portion 23 deforms toward the inner periphery of the case 2. pressed against the surface. Thereby, the seal member 20 is held in a state where it is press-fitted into the inner circumferential surface of the case 2. In this embodiment, the axially inner end of the cylindrical portion 23 faces the tip (radially outer end) of the seal forming portion 10 in the radial direction. As a result, the cylindrical portion 23 and the seal forming portion 10 reduce the gap between the case 2 and the shaft member 3, thereby improving sealing performance and suppressing the area occupied by the seal structure. ing.

On the other hand, the main lip 24 of this example is inclined with respect to the axial and radial directions so that it extends toward the seal forming portion 10 in the axial direction and toward the case 2 in the radial direction. There is. More specifically, the main lip 24 in this embodiment extends radially outward from the end of the support portion 22 on the shaft member 3 side. In other words, the main lip 24 is located on the outside in the axial direction and on the side of the shaft member in the radial direction, and is located on the inside in the axial direction and on the side of the case 2 in the radial direction. The main lip 24 is formed into a tapered cylindrical shape. The tapered cylindrical shape forming the main lip 24 tapers outward in the axial direction. Further, in this embodiment, the main lip 24 is formed as a part of the above-mentioned covering body 21B, and is formed at the timing when the covering body 21B is provided on the core bar 21A.

The angle α that the main lip 24 makes with the axial direction is not particularly limited, but is preferably 30 degrees or more and 60 degrees or less. This is because if the angle α is too small, for example, when the main lip 24 is brought into contact with the seal forming part 10, the main lip 24 may be excessively deformed in the axial direction, or the flow of lubricating oil may cause the main lip 24 to deform outward in the radial direction. This is because the main lip 24 is likely to be reversed when receiving force from the main lip 24. Furthermore, if the angle α is too large, the pressing force of the main lip 24 against the seal forming portion 10 tends to become weak. According to the knowledge of the inventor of the present invention, it has been found that the angle α formed by the main lip 24 with the axial direction is particularly preferably 45 degrees. It is preferable that the angle is .5 degrees or more and 45.5 degrees or less.

Further, in this embodiment, as is clear from FIG. 2, the main lip 24 has a garter springless structure in which the main lip 24 is brought into close contact with the seal forming part 10 by its own elastic deformation upon contact with the seal forming part 10. . That is, the main lip in a general sealing member has a configuration in which it is tightened radially inward by an annular spring member (garter spring) and pressed against the inner circumferential surface of the shaft member, but the main lip 24 in this embodiment has a configuration that ensures sealing performance without using a spring member as described above.

Further, in the present embodiment, at the end of the seal member 20 on the radially inner side (shaft member 3 side) of the support portion 22, the seal member 20 is provided with a portion that extends tapered toward the radially inner side and contacts the outer circumferential surface of the shaft member 3. A dust lip 25 is further provided. The dust lip 25 extends so as to be inclined outward in the axial direction with respect to the radial direction. Such a dust lip 25 is provided mainly for the purpose of preventing dust from entering from the outside of the rotating machine 1 into the inside, that is, into the lubricating oil storage space S. Note that the support portion 22 in this embodiment refers to a portion of the base portion 21 that extends in the radial direction excluding the dust lip 25, and refers to a portion that does not come into contact with the shaft member 3 by itself.

Next, the operation of this embodiment will be explained.

When sealing the gap between the case 2 and the shaft member 3, in this embodiment, the seal member 20 rotates the main lip 24 to the seal forming portion 10 in the gap between the case 2 and the shaft member 3. By contacting them from the outside in the axial direction of the machine 1, the gap between the case 2 and the shaft member 3 can be sealed. By forming the seal, leakage of lubricant from the lubricant storage space S can be effectively prevented. In this sealed state, the main lip 24 extends from the annular support part 22 located on the axially outer side of the seal forming part 10 toward the seal forming part 10, and directly axially contacts the seal forming part 10 or dusts. In such a configuration, the restriction on the dimensional freedom in the radial direction of the main lip 24 exerted by the support portion 22 is relaxed, so that the diameter of the main lip 24 is It becomes easier to ensure a large dimension in the direction. As a result, by enlarging only the main lip 24, it is possible to ensure strong sealing performance without strongly pressing the main lip 24 against the seal forming part 10, and the entire seal member 20 can be downsized and simplified. It becomes possible.

Specifically, in this embodiment, the size of the main lip 24 in the radial direction is increased by inclining the main lip 24 with respect to the axial direction and the radial direction. While ensuring strong sealing performance by increasing the size of the main lip 24, the axis of the cylindrical portion 23 in the sealing member 20 does not need to be made excessively large in order to ensure the sealing performance of the main lip 24. By making the dimension in the radial direction smaller than the dimension in the radial direction of the support portion 22, the dimension in the axial direction of the seal member 20 is suppressed while ensuring appropriate sealing performance. In addition, the main lip 24 does not use a lip pressing wire (garter spring) used in general sealing members, that is, by adopting a garter spring-less structure, the sealing member can maintain appropriate sealing performance. 20 has an extremely simple structure.

Furthermore, since it is possible to secure a strong sealing property without strongly pressing the main lip 24 against the seal forming part 10, it is possible to secure a strong sealing property while also keeping the main lip 24 against the seal forming part 10. By being able to suppress the pressing force, it is possible to improve the mechanical efficiency of the rotating machine 1 by suppressing frictional resistance. Further, since the seal member 20 is provided so as to be located outside the seal forming portion 10 in the axial direction, it is easier to avoid undesired interference between the seal member 20 and the seal forming portion 10 etc. during assembly, and the seal member 20 It is also possible to prevent damage to the material.

Therefore, according to the present embodiment described above, it is possible to achieve downsizing and simplification of the sealing member 20, and to improve the ease of assembly, while ensuring appropriate sealing performance, and to improve the mechanical efficiency of the rotating machine 1. Improvements can also be made. Further, in this embodiment, the main lip 24 is inclined with respect to the axial direction and the radial direction so that as it extends toward the seal forming portion 10 side, it also extends toward the case 2 side (outside in the radial direction). ing. As a result, when fluid such as lubricating oil flows from the seal forming portion 10 side to the seal member 20 side, that is, when fluid such as lubricating oil leaks outward in the axial direction, the main lip 24 moves toward the seal forming portion 10. This increases the adhesion of the main lip 24 to the seal forming portion 10. Thereby, sealing performance can be effectively improved at the timing when sealing is required.

Further, the main lip 24 extends from the end of the support portion 22 on the shaft member 3 side. Thereby, it becomes easy to ensure a large radial dimension of the main lip 24, and it becomes possible to bring the main lip 24 and the seal forming portion 10 into contact while suppressing the radial dimension of the seal forming portion 10. . This makes it easier to downsize and simplify the seal member 20, and also allows the seal forming section 10 to be downsized and simplified. Specifically, in this embodiment, it is possible to bring the seal forming part 10 and the main lip 24 into contact while keeping the radial dimension of the seal forming part 10 relatively suppressed.

Furthermore, although it has been explained that the angle α that the main lip 24 makes with the axial direction is preferably 44.5 degrees or more and 45.5 degrees or less, if the angle α is approximately 45 degrees, the main lip 24 can be sealed. The main lip 24 is prevented from deforming excessively in the axial direction when it comes into contact with the forming part 10, and the main lip 24 is prevented from deforming excessively in the axial direction, and when a fluid such as lubricating oil flows from the seal forming part 10 side to the sealing member 20 side, the main lip 24 is properly deformed. The main lip 24 is brought into close contact with the seal forming portion. Therefore, good sealing performance can be ensured while effectively suppressing frictional resistance. Furthermore, in this embodiment, since the seal forming portion 10 is integrated with the shaft member 3, an increase in the number of parts can be suppressed.

<Second embodiment>
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a sectional view of a main part of a rotating machine to which the seal structure according to the second embodiment is applied. Components in this embodiment that are similar to those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 3, this embodiment differs from the first embodiment in that a sub-lip 26 is further provided on the sealing member 20. The sub lip 26 is provided on the support part 22 so as to extend from the support part 22 along the main lip 24, and its tip is in contact with the seal forming part 10 in the axial direction. Like the main lip 24, the sub-lip 26 is also formed as a part of the covering body 21B, and is formed at the timing when the covering body 21B is provided on the core bar 21A. According to the configuration according to the second embodiment, the sealing performance of the seal member 20 can be improved.

<Third embodiment>
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a sectional view of a main part of a rotating machine to which a seal structure according to a third embodiment is applied. Components in this embodiment that are similar to those in the first and second embodiments are denoted by the same reference numerals, and explanations thereof will be omitted.

As shown in FIG. 4, in this embodiment, the seal forming portion 10 is constituted by an inner race 41A of a bearing 50 provided between the case 2 and the shaft member 3. Specifically, in this embodiment, unlike the first embodiment, a bearing 50 for holding the rolling element 4 is provided between the case 2 and the shaft member 3, and the inner ring raceway surface 4A of the rolling element 4 is provided between the case 2 and the shaft member 3. is formed by the inner surface of the inner race 41A. The inner race 41A protrudes from the outer peripheral surface of the shaft member 3 in the radial direction, and a portion of the inner race 41A that protrudes in this way constitutes the seal forming portion 10.

According to the configuration of the third embodiment, since the bearing 50 also serves as the seal forming part 10, an increase in the number of parts can be suppressed. Moreover, since the outer race or inner race of a bearing generally has a smooth surface finish, it is possible to obtain high sealing performance when the main lip 24 and the inner race 41A come into contact with each other while suppressing processing costs. This effect can also be obtained.

<Fourth embodiment>
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a sectional view of a main part of a rotating machine to which a seal structure according to a fourth embodiment is applied. Components in this embodiment that are similar to those in the first to third embodiments are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 5, in this embodiment, the seal forming portion 10 is separate from the shaft member 3. Specifically, a part of the seal surface forming member 40 removably provided on the shaft member 3 constitutes the seal forming portion 10 . The seal surface forming member 40 integrally includes a mounting cylindrical portion 41 that is fitted into the outer circumferential surface of the shaft member 3 and a seal forming portion 10 that projects from the mounting cylindrical portion 41 in the radial direction. According to the configuration of the fourth embodiment, the seal structure can be configured simply.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, in each of the embodiments described above, the seal forming part 10 is provided in the shaft member 3 and the seal member 20 is provided in the case 2; It may be provided on the shaft member 3. When the seal forming part 10 is provided in the case 2, the seal forming part 10 may be formed by an outer race of a bearing. Further, when the seal member 20 is provided on the shaft member 3 and the seal forming part 10 is provided on the case 2, the main lip 24 is inclined with respect to the axial direction and the radial direction, and on the outside in the axial direction, It may be located on the side of the case in the radial direction, and on the side opposite to the outside in the axial direction, and on the side of the shaft member in the radial direction.

DESCRIPTION OF SYMBOLS 1... Rotating machine, 2... Case, 3... Shaft member, 4... Rolling element, 4A... Inner ring raceway surface, 4B... Outer ring raceway surface, 41A... Inner race, 41B... Outer race, 50... Bearing, 10... Seal forming part , 20... Seal member, 21... Base part, 21A... Core bar, 21B... Covering body, 22... Support part, 23... Cylindrical part, 24... Main lip, 25... Dust lip, 40... Seal surface forming member, 41 ...Mounting cylindrical part, L1...Central axis line.

Claims (10)

In a rotating machine including a case and a shaft member arranged in the case so as to be rotatable relative to the case, lubricant oil leaks from a lubricant storage space located between the case and the shaft member. A seal structure for preventing
comprising a sealing member that seals a gap formed between the case and the shaft member,
a seal forming part connected to one of the case and the shaft member and located between the case and the shaft member;
The seal member is provided on the other of the case and the shaft member, and is disposed on the outer side of the seal forming portion away from the lubricating oil storage space in the axial direction,
The sealing member includes: an annular support portion that faces the seal forming portion from the outside in the axial direction; a lip that connects to the support portion and forms a seal between the seal forming portion; the case; a second lip extending radially from an end of the support portion on the one side of the shaft member and contacting the case and the one of the shaft members;
The lip extends from the outer end in the axial direction, which is connected to the support part, toward the seal forming part in the axial direction, and toward the other of the case and the shaft member. and the lip is inclined with respect to the axial direction and the radial direction so as to extend from the end opposite to the outside in the axial direction when the seal member is provided in the case. It has a cylindrical shape that tapers toward the outer end in the axial direction, or when the seal member is provided on the shaft member, it extends from the outer end in the axial direction toward the opposite end thereof. It has a tapered cylindrical shape,
The second lip extends from the end of the support part so as to be inclined toward the outer side in the axial direction with respect to the radial direction. The seal structure for a rotating machine according to claim 1, wherein the lip is connected to the end portion of the support portion on the one side of the case and the shaft member. An acute angle between the center axis and a straight line passing from the outer end to the inner end of the lip in the radial direction and intersecting the center axis of the shaft member extending in the axial direction, The seal structure for a rotating machine according to claim 1 or 2, wherein the angle is 44.5 degrees or more and 45.5 degrees or less. The sealing member has a cylindrical portion that is fitted into the inner circumferential surface of the case when provided in the case, or fitted into the outer circumferential surface of the shaft member when provided on the shaft member,
The support part is connected to the outer end of the cylindrical part in the axial direction,
The seal structure for a rotating machine according to any one of claims 1 to 3, wherein an axial dimension of the cylindrical portion is smaller than a radial dimension of the support portion. 5. The seal structure for a rotating machine according to claim 1, wherein the lip has a garter springless structure that forms the seal with the seal forming portion by elastic deformation of the lip. The seal structure for a rotating machine according to any one of claims 1 to 5, wherein the seal forming portion is separate from the one of the case and the shaft member. The seal structure for a rotating machine according to any one of claims 1 to 5, wherein the seal forming portion is integral with the one of the case and the shaft member. The seal forming portion is provided between the case and the shaft member, and when the seal member is provided on the shaft member, the seal forming portion is fitted into and connected to the inner circumferential surface of the case, and is radially connected to the inner circumferential surface of the case. an outer race or an inner race of a bearing that protrudes in a direction, or, when the seal member is provided in the case, is fitted and connected to the outer circumferential surface of the shaft member and protrudes in the radial direction from the outer circumferential surface of the shaft member; The seal structure for a rotating machine according to any one of claims 1 to 5. 9. The seal structure for a rotating machine according to claim 1, wherein the seal forming portion is provided on the shaft member, and the seal member is provided on the case. A rotary machine comprising the rotary machine seal structure according to any one of claims 1 to 9.

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