Plummer block

Abstract

This plummer block allows for changes to the seal specifications without disassembling the bearing housing. [Solution] 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. 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, so that the seal member is in close contact with the outer circumferential surface of the shaft.

Description

Technical Field

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

Background Art

[0002] As a plasma block, conventionally, there is 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 screw 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] Furthermore, the lower box 3B comprises a semi-cylindrical lower box body 3B1 into which the lower half of the bearing 2 is fitted, and a base member 3B2 that receives the lower box body 3B1. The base member 3B2 is provided with connecting protrusions 9, 9, which have receiving surfaces 9a, 9a that contact the lower surfaces 8a of the connecting protrusions 3A2, 3A2 of the upper box 3A when the upper box 3A and the lower box 3B are superimposed. In this case, each connecting protrusion 9, 9 is erected from the radially protruding flanges 10, 10 of the base member 3B2. The upper surfaces of the connecting protrusions 9, 9 are provided with screw holes 11, 11 corresponding to the through holes 7, 7 of the connecting protrusions 3A2, 3A2. As shown in Figure 8, semi-circular inner flanges 3B1a, 3B1b are formed at the axial ends of the lower box body 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 these recessed circumferential grooves 12a, 12a. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Utility Model Publication No. 7-86271 [Overview of the project] [Problems that the invention aims to solve]

[0009] Incidentally, in a seal structure equipped with such 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 such that a seal groove 17 for seal fitting is provided 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. As a result, it was not possible to change the seal structure itself after the seal groove 17 had been machined. Consequently, if it was necessary to change the specifications of the seal structure after it had been installed in the equipment, it was necessary to replace the bearing housing itself. Therefore, 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. [Means for solving the problem]

[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 receiver 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 receiver from the bearing housing.

[0019] The sealing device preferably has an upper and lower split structure. In this way, if the sealing device has an upper and lower split structure, the installation and removal operations of the sealing device will be facilitated. Also, in the first plasma block, at least one sealing member may be in sliding contact with the shaft. By configuring in this way, a stable sealing mechanism is exhibited.

[0020] It is preferable to enable the mounting of the seal member receiver on the inner peripheral surface of the axial end opening of the bearing housing by inserting the seal member receiver from the outside in the axial direction to the inside in the axial direction. By configuring in this way, the installation and removal operations of the seal member receiver are facilitated, and the installation and removal operations of the sealing device are further facilitated.

[0021] An outer flange portion may be provided that protrudes radially outward from the outer portion in the axial direction of the outer peripheral surface of the seal member receiver and contacts the outer end portion of the axial end opening of the bearing housing. By providing in this way, the outer flange portion serves as a stopper when the seal member receiver is inserted into the bearing housing, and the seal member receiver can be mounted at a stable axial position.

[0022] In the second plasma 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. Therefore, since the seal member does not slide in contact (slide in contact) with the shaft, wear of the seal member does not occur, and it has excellent durability.

Effects of the Invention

[0023] In the present invention, when changing the specifications of the sealing device (seal device), the specifications of the sealing device can be changed by removing the seal member receiver from the bearing housing. Moreover, there is no need to replace the bearing housing itself, and it has excellent maintainability.

Brief Description of the Drawings

[0024] [Figure 1] It is a perspective view of a state where the sealing device (seal structure) is separated as viewed from one opening side of the plasma block according to the present invention. [Figure 2] It is an enlarged schematic cross-sectional view of the main part of the sealing device (sealing structure). [Figure 3] It is a perspective view of the state where the sealing device (sealing structure) is separated as viewed from the other opening side of the plasma block according to the present invention. [Figure 4] It is a schematic view showing the connection structure of the sealing device (sealing structure). [Figure 5] Another embodiment of the sealing device (sealing structure) is shown. (a) is an enlarged cross-sectional view of the main part when having two lips, and (b) is an enlarged cross-sectional view of the main part when a labyrinth seal is formed. [Figure 6] It is a front view of a general plasma block. [Figure 7] It is a plan view of the plasma block shown in FIG. 6. [Figure 8] It is a cross-sectional view of the plasma block shown in FIG. 6. [Figure 9] It is a schematic cross-sectional view of the sealing structure of a general plasma block.

Mode for Carrying Out the Invention

[0025] Hereinafter, embodiments of the present invention will be described based on FIGS. 1 to 5.

[0026] As shown in FIG. 2, the plasma block of the present invention includes a rolling bearing 22 that rotatably supports a shaft 21, and a bearing box 23 that houses the rolling bearing 22.

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

[0028] The upper box 23A comprises a semi-cylindrical upper box body 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 23A1. Through holes 27, 27 are formed in the connecting protrusions 23A2 and 23A3 into which the shafts of bolt members are fitted. In addition, semi-circular inner flanges 23A1a and 23A1b are formed at both axially open ends of the upper box body 23A1.

[0029] Furthermore, the lower box 23B comprises a semi-cylindrical lower box body 23B1 into which the lower half of the bearing 22 is fitted, and a base member 23B2 that receives the lower box body 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 and 27 of the connecting protrusions 23A2 and 23A3, in a state where the lower surfaces 28a and 28b of the connecting protrusions 23A2 and 23A3 are in contact with the receiving surfaces 29a and 29b of the connecting protrusions 29A and 29B. In addition, semicircular 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 bolt member's shaft into the threaded hole of the connecting projections 29A and 29B.

[0031] In this configuration, with the upper box 3A and 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. Sealing devices S are attached to the inner flanges 24A and 24B, respectively.

[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 in 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 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 body 31A1a and 31B1a.

[0034] Furthermore, circumferential recesses 32, 32 are provided on the inner diameter surfaces of the semi-circular bodies 31A1a, 31B1a, and ring-shaped sealing members 33 are fitted into these circumferential recesses 32, 32. In this case, the semi-circular bodies 31A1a, 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, 31B1b abut against the outer edges of the inner flanges 23A1a, ​​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 concave 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 concave 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 explanations are 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 explanations are 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 outward direction toward the axial inward 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] The seal member receiver 31 may also be provided with outer flanges 31A1b and 31B1b that protrude radially outward from the axially outward portion of its outer circumferential surface and contact the outer end of the axial end opening of the bearing housing 23. With this arrangement, the outer flanges 31A1b and 31B1b act as stoppers when inserting the seal member receiver 31 into the bearing housing 23, allowing the seal member receiver 31 to be mounted in a stable axial position.

[0042] Next, Figures 5(a) and 5(b) show another embodiment of the sealing device, where Figure 5(a) includes two sealing members. In this case, the sealing member receiver 31 is provided with two circumferential recesses 32, 32 into which the sealing members 33 are fitted. Furthermore, the circumferential recesses 32, 32 have a trapezoidal cross-section that widens towards the opening. Therefore, the cross-sectional shape of the sealing member 33 corresponds to the cross-sectional shape of the circumferential recesses 32. In this way, a device equipped with multiple sealing members 33 exhibits a stable sealing mechanism.

[0043] In the sealing device shown in Figure 4(b), 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. Specifically, an uneven portion 46 is formed on the inner diameter surface of the seal member receiver 31, and a recessed portion 47 is formed on the outer diameter surface of the seal member 33 that fits into the uneven portion 46 of the seal member receiver 31 with a small gap.

[0044] In this configuration of the labyrinth seal section 45, the seal member 33 does not slide against the shaft, thus preventing wear and tear on the seal member 33 and resulting in superior durability. Furthermore, since the seal member 33 does not slide against the shaft 21 or the seal member receiving body 31, the seal member 33 in this case can 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. Furthermore, 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 may be the case that only two bolts are used, one on each side. [Explanation of Symbols]

[0046] 21 Shaft 22 bearings 23 Bearing housing 30A Axial end opening 30B Axial end opening 31 Seal member receiver 31A1b, 31B1b Outer flange 33 sealing member 45 Labyrinth seal section 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, The plummer block is characterized by comprising a sealing member receiver that is detachably mounted on the inner circumferential surface of the axial end opening of the bearing housing, and a sealing member that is fitted into a circumferential recess formed on the inner diameter surface of the sealing 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, The sealing device comprises a seal member receiver 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, characterized in that 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 seal 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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