Plummer block

Abstract

This plummer block comprises a bearing that rotatably supports a shaft, a bearing box that houses the bearing, and a sealing device sealing the space between the inner circumferential surface of an axial end opening of the bearing box and the outer circumferential surface of the shaft. The sealing device comprises: a seal member receiving body that is removably attached to the inner circumferential surface of the axial end opening of the bearing box; and a seal member that is fitted into a circumferential recess formed in an inner-diameter surface of the seal member receiving body. The seal member is in close contact with the outer circumferential surface of the shaft.

Description

Plasma block

[0001] The present invention relates to a plasma block including a bearing and a bearing housing that supports the bearing.

[0002] As a plasma block, there is a conventional one described in Patent Document 1. Generally, as shown in FIGS. 6 to 9, the plasma block includes a rolling bearing 2 that rotatably supports a shaft 1 and a bearing housing 3 that houses the rolling bearing 2.

[0003] The bearing housing 3 has an upper housing 3A above and a lower housing 3B below. The upper housing 3A and the lower housing 3B are combined to form the bearing housing 3. The upper housing 3A and the lower housing 3B are connected and integrated via a bolt member 4. The bolt member 4 includes a head 5 and a shaft portion 6 having a male thread portion.

[0004] The upper housing 3A includes a semi-cylindrical upper housing main body portion 3A1 into which the upper half of the bearing 2 is fitted, and connecting convex portions 3A2, 3A2 provided at side end portions of the upper housing main body portion 3A1. Through holes 7, 7 into which the shaft portion 6 of the bolt member 4 is inserted are formed in the connecting convex portions 3A2, 3A2. Further, as shown in FIG. 8, semi-arc-shaped inner flange portions 3A1a, 3A1b are formed at axial end portions of the upper housing main body portion 3A1.

[0005] The lower housing 3B includes a semi-cylindrical lower housing main body portion 3B1 into which the lower half of the bearing 2 is fitted, and a base member 3B2 that receives the lower housing main body portion 3B1. The base member 3B2 is provided with connecting convex portions 9, 9 having receiving surfaces 9a, 9a on which the lower surfaces 8a of the connecting convex portions 3A2, 3A2 of the upper housing 3A abut when the upper housing 3A and the lower housing 3B are overlapped. In this case, the connecting convex portions 9, 9 are erected from radially protruding flanges 10, 10 of the base member 3B2. Thread holes 11, 11 corresponding to the through holes 7, 7 of the connecting convex portions 3A2, 3A2 are provided on the upper surfaces of the connecting convex portions 9, 9. As shown in FIG. 8, semi-arc-shaped inner flange portions 3B1a, 3B1b are formed at axial end portions of the lower housing main body portion 3B1.

[0006] Therefore, as shown in Figure 6, the upper box 3A and the lower box 3B are connected by inserting the shaft portion 6 of the bolt member 4 into the through holes 7, 7 of the connecting protrusions 3A2, 3A2 from above, and screwing the male threaded portion of the shaft portion 6 of the bolt member 4 into the threaded holes 11, 11 of the connecting protrusions 9, 9.

[0007] In this configuration, with the upper box 3A and the lower box 3B connected to form the bearing housing 3, as shown in Figure 8, the inner flanges 3A1a and 3A1b of the upper box 3A and the inner flanges 3B1a and 3B1b of the lower box 3B form ring-shaped inner flanges 12, 12. Recessed circumferential grooves 12a, 12a are provided on the inner diameter surfaces of these inner flanges 12, 12, and sealing members 13, 13 are fitted into each of the recessed circumferential grooves 12a, 12a.

[0008] Japanese Utility Model Publication No. 7-86271

[0009] Incidentally, in a seal structure equipped with a plummer block seal member 13, circumferential grooves 12a, 12a are provided on the inner diameter surfaces of the inner flanges 3A1a, ​​3A1b of the upper box 3A and the inner diameter surfaces of the inner flanges 3B1a, 3B1b of the lower box 3B, and the seal members 13, 13 are fitted into these circumferential grooves 12a, 12a.

[0010] In other words, as shown in Figure 9, the seal structure of the plummer block is provided with a seal groove 17 for seal fitting on the inner circumferential surface 16a of the axial end opening 16 of the bearing housing 15, and a seal member 18 is fitted into the seal groove 17.

[0011] Therefore, the diameter of the seal groove 17 was machined according to the shape and specifications of the seal member 18. Consequently, the seal structure itself could not be changed after the seal groove 17 had been machined. Therefore, if it was necessary to change the specifications of the seal structure after it had been installed in the equipment, the bearing housing itself had to be replaced. Consequently, the replacement work was troublesome and costly.

[0012] Furthermore, without changing the shape or size of the seal groove 17, various types of seal members 18 can be provided, and the specifications of the seal structure can be changed by changing the corresponding seal member when desired. However, in such cases, commercially available seal members (oil seals) that are commonly used cannot be used, resulting in high costs. Moreover, when replacing the seal member, it is necessary to split the bearing housing into upper and lower halves, making the replacement work extensive and requiring the installed equipment to be shut down for a long period of time.

[0013] Incidentally, the device described in Patent Document 1 includes a rotating ring attached to a shaft and a cover that covers the rotating ring, with a sealing material rotatably fitted in the gap between the cover and the shaft. This configuration prevents the scattering of lubricating oil and aims to eliminate quality problems caused by the adhesion of lubricating oil to steel plates.

[0014] However, while the seal structure described in Patent Document 1 is simple and easy to maintain as a whole device, it does not allow for changes to the seal structure of the plummer block itself.

[0015] Therefore, in view of the above problems, the present invention provides a plummer block that can be used to change the seal specifications without disassembling the bearing housing.

[0016] The first plummer block of the present invention comprises a bearing that rotatably supports a shaft, a bearing housing that houses the bearing, and a sealing device that seals the space between the inner circumferential surface of the axial end opening of the bearing housing and the outer circumferential surface of the shaft, wherein the sealing device comprises a seal member receiver that is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, and a seal member that is fitted into a circumferential recess formed on the inner diameter surface of the seal member receiver and slides against the shaft.

[0017] A second plummer block of the present invention comprises a bearing that rotatably supports a shaft, a bearing housing that houses the bearing, and a sealing device that seals the space between the inner circumferential surface of the axial end opening of the bearing housing and the outer circumferential surface of the shaft, wherein the sealing device comprises a seal member receiver that is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, and a seal member fitted into a circumferential recess formed on the inner diameter surface of the seal member receiver, and a labyrinth seal portion is formed between the inner diameter surface of the seal member receiver and the outer diameter surface of the seal member.

[0018] According to the first and second plummer blocks of the present invention, since the seal member receiving body is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, the specifications of the sealing device (sealing device) can be changed by removing the seal member receiving body from the bearing housing.

[0019] The sealing device preferably has an upper and lower split structure. Such a split structure facilitates the installation and removal of the sealing device. Furthermore, in the first plummer block, at least one sealing member may slide against the shaft. This configuration provides a stable sealing mechanism.

[0020] It is preferable that the seal member receiver be inserted from the axially outward direction toward the axially inward direction, thereby enabling the seal member receiver to be mounted on the inner circumferential surface of the axial end opening of the bearing housing. This configuration facilitates the installation and removal of the seal member receiver, making the installation and removal of the sealing device even easier.

[0021] The outer flange portion may be provided on the outer circumferential surface of the seal member receiver, projecting radially outward and contacting the outer end of the axial end opening of the bearing housing. With this configuration, the outer flange portion acts as a stopper when inserting the seal member receiver into the bearing housing, allowing the seal member receiver to be mounted in a stable axial position.

[0022] In the second plummer block, a labyrinth seal portion is formed between the inner diameter surface of the seal member receiver and the outer diameter surface of the seal member. Since the seal member does not slide against the shaft, wear of the seal member does not occur, resulting in excellent durability.

[0023] In this invention, when changing the specifications of a sealing device (sealing device), the specifications of the sealing device can be changed by removing the sealing member receiver from the bearing housing, and moreover, there is no need to replace the bearing housing itself, resulting in excellent maintainability.

[0024] This is a perspective view of the plummer block according to the present invention, showing the sealing device (seal structure) in a separated state, as seen from one opening side. This is a simplified enlarged cross-sectional view of the main part of the sealing device (seal structure). This is a perspective view of the plummer block according to the present invention, showing the sealing device (seal structure) in a separated state, as seen from the other opening side. This is a simplified diagram showing the connecting structure of the sealing device (seal structure). This shows another embodiment of the sealing device (seal structure), showing a simplified cross-sectional view of the main part when it has two lips. This shows another embodiment of the sealing device (seal structure), showing a simplified cross-sectional view of the main part when a labyrinth seal is formed. This is a front view of a typical plummer block. This is a plan view of the plummer block shown in Figure 6. This is a cross-sectional view of the plummer block shown in Figure 6. This is a simplified cross-sectional view of the seal structure of a typical plummer block.

[0025] Embodiments of the present invention will be described below with reference to Figures 1 to 5B.

[0026] As shown in Figure 2, the plummer block of the present invention comprises a rolling bearing 22 that rotatably supports a shaft 21, and a bearing housing 23 that houses the rolling bearing 22.

[0027] As shown in Figures 1 to 3, the bearing housing 23 has an upper box 23A and a lower box 23B. The upper box 23A and the lower box 23B are combined to form the bearing housing 23. The upper box 23A and the lower box 23B are connected and integrated via bolt members (not shown).

[0028] The upper box 23A comprises a semi-cylindrical upper box body portion 23A1 into which the upper half of the bearing 22 is fitted, and connecting protrusions 23A2 and 23A3 provided at the side ends of the upper box body portion 23A1. Through holes 27, 27 are formed in the connecting protrusions 23A2 and 23A3 into which the shaft portion of the bolt member is fitted. In addition, semi-circular inner flange portions 23A1a and 23A1b are formed at both axially open ends of the upper box body portion 23A1.

[0029] Furthermore, the lower box 23B comprises a semi-cylindrical lower box body portion 23B1 into which the lower half of the bearing 22 is fitted, and a base member 23B2 that receives the lower box body portion 3B1. The base member 23B2 is provided with connecting protrusions 29A and 29B, which have receiving surfaces 29a and 29b that contact the lower surfaces 28a and 28b of the connecting protrusions 23A2 and 23A2 of the upper box 23A when the upper box 23A and the lower box 23B are stacked on top of each other. In this case, each connecting protrusion 29A and 29B is erected from radially protruding flanges 30a and 30b of the base member 23B2. Furthermore, when the upper box 23A and the lower box 23B are superimposed, the connecting protrusions 29A and 29B are provided with screw holes (not shown) corresponding to the through holes 27, 27 of the connecting protrusions 23A2 and 23A3, in which the lower surfaces 28a and 28b of the connecting protrusions 23A2 and 23A3 abut against the receiving surfaces 29a and 29b of the connecting protrusions 29A and 29B. In addition, semi-circular inner flanges 23B1a and 23B1b are formed at the axial ends of the lower box body 23B1.

[0030] Therefore, the upper box 23A and the lower box 23B are connected by inserting the shaft portion of the bolt member into the through hole 27 of the connecting projections 23A2 and 23A3 from above, and screwing the male threaded portion of the shaft portion of the bolt member into the threaded hole of the connecting projections 29A and 29B.

[0031] In this configuration, with the upper box 3A and the lower box 3B connected to form the bearing housing 3, the inner flanges 23A1a and 23A1b of the upper box 23A and the inner flanges 23B1a and 23B1b of the lower box 23B form ring-shaped inner flanges 24A and 24B. A sealing device S is attached to each of the inner flanges 24A and 24B.

[0032] The sealing device S comprises a seal member receiver 31 that is detachably mounted on the inner circumferential surface of the axial end openings 30A and 30B of the bearing housing 23, and a seal member 33 that is fitted into a circumferential recess 32 formed on the inner diameter surface of the seal member receiver 31. The seal member 33 is made of an elastic material such as rubber or resin.

[0033] The sealing device S is provided at a pair of axial end openings 30A and 30B at both ends in the axial direction. First, the sealing device S at one of the openings 30A will be described. The seal member receiving body 31 consists of two separators 31A1 and 31B1. Each separator 31A1 and 31B1 consists of a semi-circular arc body 31A1a and 31B1a with a rectangular cross-section, and an outer flange portion 31A1b and 31B1b provided on the outer end side of the semi-circular arc body 31A1a and 31B1a.

[0034] Furthermore, circumferential recesses 32, 32 are provided on the inner diameter surfaces of the semi-circular bodies 31A1a and 31B1a, and ring-shaped sealing members 33 are fitted into these circumferential recesses 32, 32. In this case, the semi-circular bodies 31A1a and 31B1a can be fitted into the bearing housing by sliding them from the axial outward to the axial inward direction, and in the fitted state, the outer flanges 31A1b and 31B1b abut against the outer edges of the inner flanges 23A1a and 23B1a.

[0035] In this case, as shown in Figure 4, the upper and lower semi-circular bodies 31A1a and 31B1a can be joined together in a ring shape by a bolt member (reamer bolt) 35 (i.e., the end face (lower end face) of the semi-circular body 31A1a and the end face (upper end face) of the semi-circular body 31B1a are joined together as shown in Figure 4). Specifically, a through hole 36 is provided in the peripheral wall of the upper semi-circular body 31A1a, and a screw hole 37 is provided in the end face of the lower semi-circular body 31B1a. The bolt member 35 is inserted into the through hole 36 of the upper semi-circular body 31A1a, and the male threaded portion 35a of the bolt member 35 is screwed into the screw hole 37 of the lower semi-circular body 31B1a, thereby integrating the upper and lower semi-circular bodies 31A1a and 31B1a. In this case, the through-hole 36 consists of an upper large-diameter portion 36a and a lower small-diameter portion 36b, and the head 35b of the bolt member 35 engages with the stepped surface 36c between the large-diameter portion 36a and the small-diameter portion 36b.

[0036] Furthermore, the seal member receiver 31 is fixed by set screws 40 that are screwed into the inner flange portions 23A1a and 23B1a. In addition, a seal ring (O-ring) 37 is interposed between the inner flange portions 23A1a and 23B1a and the seal member receiver 31. That is, a recessed circumferential groove is provided on the inner circumferential surface of the inner flange portions 23A1a and 23B1a, and the seal ring 37 is fitted into this recessed circumferential groove.

[0037] Furthermore, the sealing device S attached to the other axial end opening 30B shown in Figure 3 has the same configuration as the sealing device S attached to the one axial end opening 30A shown in Figure 1, so their explanation will be omitted. That is, the sealing member receiver 31 is attached to the inner flange portions 23A1b and 23B1b of the other opening, and the mounting structure is the same, so they are denoted by the reference numerals shown in Figure 1 and their explanation will be omitted.

[0038] According to the plummer block of the present invention, since the seal member receiver 31 is detachably mounted on the inner circumferential surface of the axial end openings 30A and 30B of the bearing housing 23, when changing the specifications of the sealing device (sealing device S), the specifications of the sealing device S can be changed by removing the seal member receiver 31 from the bearing housing 23, and moreover, there is no need to replace the bearing housing itself, resulting in excellent maintainability.

[0039] The sealing device S preferably has an upper and lower split structure. Having such a split structure makes it easier to install and remove the sealing device S.

[0040] It is preferable to insert the seal member receiver 31 from the axial outer direction to the axial inner direction, thereby enabling the seal member receiver 31 to be mounted on the inner circumferential surface of the axial end openings 30A and 30B of the bearing housing 23. This configuration facilitates the installation and removal of the seal member receiver 31, and further simplifies the installation and removal of the sealing device S.

[0041] An outer flange portion 31A1b and 31B1b that protrudes radially outward from the axially outer portion of the outer peripheral surface of the seal member receiver 31 and contacts the outer end portion of the axially end opening of the bearing housing 23 may be provided. By providing it in this way, the outer flange portions 31A1b and 31B1b serve as stoppers when the seal member receiver 31 is inserted into the bearing housing 23, and the seal member receiver 31 can be mounted at a stable axial position.

[0042] Next, FIGS. 5A and 5B show another embodiment of the sealing device. In FIG. 5A, two seal members are provided. In this case, two circumferential recesses 32 and 32 into which the seal members 33 are fitted are provided in the seal member receiver 31. Further, the circumferential recesses 32 and 32 are trapezoidal in cross section with the opening side enlarged. Therefore, the cross-sectional shape of the seal member 33 corresponds to the cross-sectional shape of the circumferential recess 32. Thus, when a plurality of seal members 33 are provided, a stable sealing mechanism is exhibited.

[0043] In the sealing device shown in FIG. 5B, a labyrinth seal portion 45 is formed between the inner diameter surface of the seal member receiver 31 and the outer diameter surface of the seal member 33. That is, an uneven portion 46 is formed on the inner diameter surface of the seal member receiver 31, and a convex and concave portion 47 that fits into the uneven portion 46 of the seal member receiver 31 with a minute gap is formed on the outer diameter surface of the seal member 33.

[0044] In this way, when the labyrinth seal portion 45 is formed, the seal member 33 does not slide-contact (slide-contact) with the shaft, so wear and the like of the seal member 33 do not occur, and the durability is excellent. Further, since the seal member 33 does not slide or slide-contact with the shaft 21 or the seal member receiver 31, the seal member 33 in this case may be made of rubber, resin, or metal.

[0045] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be modified in various ways. Self-aligning roller bearings or self-aligning ball bearings can be used as bearings. Alternatively, one opening of the bearing housing may be closed with an end plate. The sealing member 33 may be composed of two divided parts or a single ring, corresponding to the sealing member receiving body 31. In the plummer block of the embodiment, a total of four bolts were used as connecting members for the upper box 23A and the lower box 23B, but it is also possible to use only two bolts, one for each side.

[0046] The plummer block comprises a rolling bearing that rotatably supports the shaft and a bearing housing that houses the rolling bearing. Self-aligning roller bearings or self-aligning ball bearings can be used as the bearings.

[0047] 21 Shaft 22 Bearing 23 Bearing housing 30A Axial end opening 30B Axial end opening 31 Seal member receiving body 31A1b, 31B1b Outer flange portion 33 Seal member 45 Labyrinth seal portion S Sealing device

Claims

1. A plummer block comprising a bearing that rotatably supports a shaft, a bearing housing that houses the bearing, and a sealing device that seals the space between the inner circumferential surface of the axial end opening of the bearing housing and the outer circumferential surface of the shaft, wherein the sealing device comprises a seal member receiver that is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, and a seal member that is fitted into a circumferential recess formed on the inner diameter surface of the seal member receiver and slides against the shaft.

2. A plummer block comprising a bearing that rotatably supports a shaft, a bearing housing that houses the bearing, and a sealing device that seals the space between the inner circumferential surface of the axial end opening of the bearing housing and the outer circumferential surface of the shaft, wherein the sealing device comprises a seal member receiver that is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, and a seal member fitted into a circumferential recess formed on the inner diameter surface of the seal member receiver, and a labyrinth seal portion is formed between the inner diameter surface of the seal member receiver and the outer diameter surface of the seal member.

3. The plummer block according to claim 1 or 2, characterized in that the sealing device has an upper and lower divided structure.

4. The plummer block according to claim 1, characterized in that at least one sealing member slides against the shaft.

5. The plummer block according to claim 1 or 2, characterized in that the seal member receiving body can be mounted on the inner circumferential surface of the axial end opening of the bearing housing by inserting the seal member receiving body from the axial outward to the axial inward direction.

6. The plummer block according to claim 5, characterized in that an outer flange portion is provided on the outer peripheral surface of the sealing member receiving body, projecting radially outward from the axially outward portion and contacting the outer end of the axial end opening of the bearing housing.

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