WO2014102887A1

WO2014102887A1 - Sealing structure and conveyance robot provided with same

Info

Publication number: WO2014102887A1
Application number: PCT/JP2012/008465
Authority: WO
Inventors: 寛晃安藤
Original assignee: 平田機工株式会社
Priority date: 2012-12-28
Filing date: 2012-12-28
Publication date: 2014-07-03
Also published as: JPWO2014102887A1; JP6101417B2; TWI532574B; TW201433425A

Abstract

The present invention addresses the problem of providing a sealing structure for a rotating section, the structure using a magnetic fluid seal. With the sealing structure, stable sealing performance is obtained even if a deformation such as bending of a supporting shaft occurs in the rotating section. A sealing structure (30) for sealing the connection (20) between a first arm (11) and a second arm (12) that is connected to the first arm (11) via a rotation shaft (23), wherein the sealing structure (30) comprises a magnetic sealing section (50) that uses a magnetic fluid and a bellows sealing section (40) configured from a bellows (41). With said sealing structure (30), because the sealing structure (30) for the connection (20) between the two rotatably connected members (11, 12) is configured using a magnetic sealing section (50) and a bellows (41), bending of the rotation shaft (23) of the connection (20) can be absorbed by the bellows (41) while rotatability is maintained, and a stable sealed state is secured.

Description

Sealed structure and transfer robot equipped with the same

The present invention relates to a sealing structure, and more particularly to a sealing structure that seals a driving part of a machine such as a transfer device or a transfer robot.

In a machine such as a transfer device, the generation of dust or the like in the drive part may be a problem. In particular, in a machine used in an airtight container such as a vacuum chamber or a clean room, it is necessary to prevent scattering and outflow of substances such as dust generated in a driving part of the machine.

For example, as a transfer device used in an airtight container, there is one in which a drive mechanism of an object support tool installed so as to be movable up and down is sealed using a bellows which is a contact-type seal member (see Patent Document 1). ). The bellows is a member having elasticity, and is used as a member that seals between members that linearly move.
Further, as a transfer robot used in a vacuum chamber, there is a robot in which a joint portion between a swing member supported by a support member and a support member is sealed with a magnetic seal unit using a magnetic fluid seal. (See Patent Document 2). The magnetic fluid seal is a contact-type seal structure in which a magnetic fluid is held in a gap between rotationally moving members, and is used for a seal of a rotational motion part such as a drive part of a transport device.

Japanese Patent Laid-Open No. 10-181870 Japanese Patent No. 4106172

By the way, the bellows is not suitable as a member that seals between members that rotate in rotation because the strength against torsion is not high.
On the other hand, as described above, the magnetic fluid seal is suitable as a seal structure for the rotary motion part. However, in order to obtain a stable sealing performance with the magnetic fluid seal, it is necessary to prevent deformation of the rotary motion part.
For this reason, in the above-described transfer robot, the magnetic seal unit is disposed between the support shaft and the support member via the elastic seal material, thereby increasing the gap due to bending (bending deformation) of the support shaft. Trying to absorb with an elastic sealant. However, the amount of change that can be absorbed by the elastic sealing material is not necessarily large.
The present invention has been made in view of such problems, and has a sealed structure of a rotary motion part using a magnetic fluid seal. For example, the rotary motion part is deformed, such as bending deformation of a support shaft. It is another object of the present invention to provide a sealed structure capable of obtaining stable sealing performance.

The invention according to the present application is a sealing structure that seals a connecting portion between a first member and a second member that is connected to the first member via a rotating shaft, and the sealing structure is magnetic. It is a sealing structure characterized by having a magnetic sealing part made of fluid and a bellows sealing part composed of a bellows.
The bellows of the bellows sealing part has one end fixed to the second member and the other end fixed to the magnetic sealing part, and the magnetic sealing part has the other end of the bellows. One fixed magnetic seal member and the other magnetic seal member fixed to the first member side, and the one magnetic seal member is disposed so that the other magnetic seal member is opposed to the other magnetic seal member. A cylindrical portion, and the other magnetic seal member includes a circumferential portion disposed to face the cylindrical portion of the one magnetic seal member, and the cylindrical portion of the one magnetic seal member The magnetic fluid is disposed between the circumference of the other magnetic seal member.
Further, a rotation synchronization mechanism for synchronizing the rotation of the one magnetic seal member and the rotation of the second member is further provided.
Further, the rotating shaft body is fixed to the second member, the one magnetic seal member is arranged inside the other magnetic seal member, and the cylindrical portion of the one magnetic seal member is The other magnetic seal member is provided with a magnetic pole member disposed opposite to the outer peripheral surface of the cylindrical portion, and the one magnetic seal member is provided with an outer peripheral surface made of a magnetic material. A magnetic fluid is disposed between the outer peripheral surface of the cylindrical portion and the magnetic pole member at the circumferential portion of the other magnetic seal member.
The rotation synchronization mechanism is provided between the rotating shaft body and the one magnetic seal member.
The rotation synchronization mechanism includes a protrusion formed on an outer peripheral surface of the rotating shaft body and a groove formed on an inner peripheral surface of the one magnetic seal member and engaged with the protrusion. Yes.
In addition, at least one engagement portion is provided by the protrusion and the groove.
Further, the rotating shaft body is fixed to the first member, the one magnetic seal member is disposed inside the other magnetic seal member, and the cylindrical portion of the one magnetic seal member is The other magnetic seal member is provided with a magnetic pole member disposed opposite to the outer peripheral surface of the cylindrical portion, and the one magnetic seal member is provided with an outer peripheral surface made of a magnetic material. A magnetic fluid is disposed between the outer peripheral surface of the cylindrical portion and the magnetic pole member at the circumferential portion of the other magnetic seal member.
Further, a synchronization mechanism for fixing the one magnetic seal member to the second member is further provided.
Further, the other magnetic seal member and the one magnetic seal member are rotatably engaged via a bearing member.
In addition, a hermetic coupling portion is further provided between the one magnetic seal member and the bellows, and a seal member made of a detachable elastic body is mounted.

Another invention according to the present application is a transfer robot including a joint portion that rotatably connects a base side member and a rotation side member, the joint portion including the base side member and the rotation side member. And a sealing structure that seals the joint part. The sealing structure includes a magnetic sealing part made of a magnetic fluid and a bellows sealing part composed of a bellows. It has.
And it is a conveyance robot provided with the joint part which connects a base side member and a rotation side member rotatably, The base side member is one of the 1st member and the 2nd member, The rotation side member is the remaining one of the first member and the second member, and the joint portion includes the rotation shaft body that connects the base side member and the rotation side member so as to be relatively rotatable. A sealing structure for sealing the joint part, the sealing structure having a magnetic sealing part made of magnetic fluid and a bellows sealing part made of a bellows, and the sealing structure is The sealed structure having the above-described configuration.

According to the invention according to the present application, since the sealing structure of the connecting portion of the two members that are rotatably connected is configured using the magnetic sealing portion and the bellows, the connecting state is maintained while maintaining the rotatable state. The bending deformation of the rotating shaft body of the part is absorbed by the bellows, and a stable sealed state is ensured.
A magnetic seal casing fixed on the bellows side is prepared, and the magnetic seal portion is configured by the magnetic seal casing, the bearing support member, and the magnetic fluid disposed between the two, so a more reliable sealed state is secured. The
In addition, since the rotation synchronization mechanism that synchronizes the rotation of the magnetic seal casing and the rotation of the second member to which the bellows is fixed is provided, torsional deformation of the bellows is reliably prevented, and a more reliable sealed state is secured.

It is a perspective view which shows an example of the conveyance robot provided with the sealing structure which concerns on invention of this application. FIG. 2A is a cross-sectional view showing a cross-section in the AA plane shown in FIG. 2B with respect to the sealing structure of the embodiment of the present invention, and FIG. It is sectional drawing which shows the cross section in the B1-B2 surface shown by A). It is an expanded sectional view which shows the principal part of the sealing structure shown by FIG. 2 (B).

10 ... Transport robot, 10a ... Leg part, 10b ... Arm part,
11: first arm (first member or second member), 11a: housing, 11b: opening of housing,
12 ... second arm (first member or second member), 12a ... housing,
13 ... Third arm (hand part),
20 ... connecting part (first connecting part), 21 ... drive motor,
22 ... reducer unit, 22a ... reducer, 22b ... output rotating part, 22c ... bearing part,
23 ... Rotating shaft,
30 ... 1st sealing structure, 40 ... Bellows sealing part, 41 ... Bellows, 42, 43 ... Connection member,
49 ... O-ring (elastic seal member), 50 ... magnetic sealing part,
51 ... cylindrical member (one magnetic seal member, magnetic seal casing),
52 ... Cylinder part, 52a ... Outer peripheral surface of the cylinder part, 53 ... Flange part,
61 ... Magnetic seal unit (the other magnetic seal member, bearing support member),
62 ... circumferential part, 63 ... magnetic pole member (pole piece), 64 ... magnetic fluid,
66 ... Bearing (bearing member),
70 ... 1st synchronization mechanism (rotation synchronization mechanism), 71 ... Projection part, 72 ... Key groove part,
72a ... the bottom of the keyway,
C: gap, P: inner space of the first sealed structure, S: work space.

Next, a transfer robot having a sealed structure according to the present invention will be described with reference to the drawings.
A transfer robot 10 shown in FIG. 1 is installed in a vacuum chamber, which is a vacuum working space with reduced pressure.

The transfer robot 10 includes a leg 10a installed on the floor of the vacuum chamber and an arm 10b installed on the upper end of the leg 10a. The arm portion 10b includes a first arm 11 that is rotatably installed at the upper end of the leg portion 10a, a second arm 12 that is rotatably attached to the distal end portion of the first arm 11, and a distal end portion of the second arm 12. A third arm 13, also referred to as a transport hand, rotatably attached to the head is provided. The first and

second arms

11 and 12 have

casings

11a and 12a (see FIG. 2B), and members such as a drive motor 21 described later can be installed in the casing. Since the

casings

11a and 12a of the

arms

11 and 12 are hermetically sealed, when the opening of the casing is sealed, the internal space of the casing is cut off from the work space S and the pressure difference is maintained. And can be sealed. Since the basic configuration such as the overall configuration of the transfer robot 10 is well known, detailed description thereof is omitted here.

As described above, the second arm (second member, rotation side member) 12 of the arm portion 10b is slidably connected to the first arm (first member 11, base side member).

A connecting portion (hereinafter referred to as a first connecting portion) 20 between the first arm 11 and the second arm 12 is a joint portion that connects the

arms

11 and 12 so as to be relatively rotatable.
The first connecting portion 20 includes a drive motor 21 installed in the first arm 11, a speed reducer unit 22 that transmits the rotation of the drive motor 21 while changing the speed, and a rotating shaft body 23 supported by the speed reducer unit 22. And.
The speed reducer unit 22 is installed in the first arm 11, and is a timing belt that transmits the rotation of the housing 22a, the output rotating part 22b, the bearing 22c, the input shaft 26, and the drive motor 21 to the input shaft 26. And 25. The housing 22a includes an opening 28 that opens upward, and a through-hole that extends downward and is formed in the center of the bottom. The output rotating part 22b can rotate in the opening 28 via a bearing 22c. is set up. A rotating shaft body 23 extending upward and an input shaft 26 extending downward through the through hole are fixed to the output rotating portion 22b. The input shaft 26 includes a gear portion 26a at the lower end portion of the shaft portion 26b, and the rotation of the drive motor 21 is transmitted to the gear portion 26a via the timing belt 25. That is, the rotation of the drive motor 21 is transmitted to the output rotating unit 22b via the timing belt 25 and the input shaft 26, and is transmitted to the rotating shaft body 23. The rotating shaft body 23 is fixed to the output rotating portion 22b so as to protrude outward (upward in FIG. 3) from an opening portion 11b formed in the housing 11a of the first arm 11. And the 2nd arm 12 is attached to the upper end part which is the front end side of the rotating shaft body 23. FIG. That is, the first arm 11 and the second arm 12 are rotatably connected via the rotating shaft body 23. Accordingly, when the drive motor 21 is operated, the second arm 12 is rotated and rotated with respect to the first arm 11.

The transfer robot 10 further includes a first sealing structure 30 that seals the first connecting portion 20. The first sealing structure 30 is a structure that seals the first connecting portion 20 in a space that is cut off from the work space S in which the transfer robot 10 is installed.

The first sealing structure 30 includes a bellows sealing part 40 fixed to the second arm side and a magnetic sealing part 50 connected to the bellows sealing part 40.

The bellows sealing part 40 includes a bellows 41 that is a cylindrical member. The bellows 41 is disposed so as to surround the rotating shaft body 23 of the first connecting portion 20. And the upper end part (one end side) of the bellows 41 is being fixed to the 2nd arm 12 by bolt fastening via the ring-shaped connection member (flange member). A magnetic hermetic seal 50 is fastened to the lower end (other end side) of the bellows 41 via a ring-shaped connecting member (flange member) 43.
The connection member 42 on the upper end side of the bellows 41 and the second arm 12 are fixed by bolt fastening with a rubber O-ring (elastic seal member) 49 interposed therebetween. Thereby, the sealing property in the connection part of the both ends of the bellows 41 is ensured. Note that the same fixing structure is also provided between the connecting member 43 on the lower end side of the bellows 41 and a cylindrical member 51 described later of the magnetic sealing portion 50, and between the magnetic seal unit 61 described later and the first arm 11.

The magnetic sealing part 50 includes a cylindrical member (one magnetic seal member) 51 to which the lower end of the bellows 41 is connected, and a magnetic seal unit (the other magnetic seal member) 61 fixed to the first arm 11 side. ing. The cylindrical member 51 is disposed inside the magnetic seal unit 61. A bearing 66 is inserted between the cylindrical member 51 and the magnetic seal unit 61. With such a configuration, smooth rotation between each other can be realized. In addition, a gap C having a constant interval can be easily formed over the entire circumference between the cylindrical member 51 and the magnetic seal unit 61. Furthermore, the cylindrical member 51 is held in a stable state by the magnetic seal unit 61 via the bearing 66, and the rotational position of the cylindrical member 51 is stabilized. That is, it can be said that the magnetic seal unit 61 and the bearing 66 are means (bearing member) for stabilizing the rotational position of the cylindrical member 51 relative to the first arm 11. When the rotational position of the cylindrical member 51 is stable, deformation (for example, torsion deformation) other than expansion and contraction of the bellows 41 is suppressed. Note that the bearings 66 are disposed at the upper end position and the lower end position of a later-described cylinder portion 52 of the cylindrical member 51, respectively.

The cylindrical member 51 is made of a steel material having magnetism that is conventionally used as a material for the rotating shaft, and includes a cylindrical portion 52 disposed so as to surround the rotating shaft body 23, an upper end of the cylindrical portion 52, and And a flange portion 53 provided at the lower end. Each flange portion 53 is a flat plate-shaped portion that spreads outward from the cylindrical portion 52 in the radial direction.

The magnetic seal unit 61 is a unit that generates a magnetic field, and includes a circumferential portion 62 that surrounds the tubular portion 52 of the tubular member 51 over the entire circumference. A magnetic pole member 63, which is a member for generating a magnetic field, is disposed on the circumferential portion 62. That is, the circumferential portion 62 having the magnetic pole member 63 is disposed to face the cylindrical portion 52 of the cylindrical member 51. The magnetic pole member 63 includes a ring-shaped magnet 63a and ring-shaped pole pieces 63b disposed above and below the magnet 63a. The magnetic fluid 64 is held between the pole pieces 63b and the outer peripheral surface 52a of the cylindrical portion 52. Therefore, when the magnetic seal unit 61 is operated, a sealed state between the tubular member 51 and the magnetic seal unit 61 is secured by the magnetic fluid 64 in a state where the second arm 12 can rotate with respect to the first arm 11. . In the present embodiment, the magnetic pole member 63 is disposed at a position adjacent to the upper and lower bearings 66, and the magnetic fluid 64 is held at a position adjacent to the upper and lower bearings 66.

The first sealing structure 30 further includes a first synchronization mechanism (rotation synchronization mechanism) 70 that synchronizes the rotation of the cylindrical member 51 and the rotation of the second arm 12. The first synchronization mechanism 70 includes a protrusion 71 formed on the outer peripheral surface of the rotary shaft body 23 and a key groove portion 72 formed on the inner peripheral surface of the cylindrical member 51. The key groove portion 72 extends in the axial direction (vertical direction) of the rotary shaft body 23. The projecting portion 71 of the rotating shaft body 23 is engaged with the key groove portion 72 in a state where a gap is secured between the tip of the projecting portion 71 and the bottom surface 72a of the key groove portion 72. With this structure, even if the rotating shaft 23 is bent and deformed, and the relative position of the protrusion 71 with respect to the key groove 72 changes, the force due to the bending deformation acts on the key groove 72 from the protrusion 71. Absent. Further, since the first synchronization mechanism 70 synchronizes the rotation of the rotating shaft body 23, that is, the rotation of the second arm 12 and the rotation of the cylindrical member 51, there is a variation in the rotation at the upper and lower ends of the bellows 41. Absent. As a result, there is no fear that the bellows 41 will be twisted, and there is no possibility that the bellows 41 will be damaged. As a result, high sealing reliability is obtained in the first sealing structure 30.

As described above, the first sealing structure 30 is arranged so as to surround the first connecting portion 20 existing between the first arm 11 and the second arm 12. One end of the first sealing structure 30, that is, the upper end of the bellows 41 is fixed in a sealed state to the housing 12 a of the second arm 12, and the other end of the first sealing structure 30, that is, the magnetic seal unit 61 of the magnetic sealing part 50 is The first arm 11 is fixed to the housing 11a in a sealed state. That is, the inner space P of the first sealing structure 30 (see FIG. 2B) is surrounded by the bottom surfaces of the casing 12a of the first sealing structure 30 and the second arm 12 in a state in which the sealing is ensured. At the same time, it communicates with the internal space of the housing of the first arm 11 through the opening 11b and is cut off from the work space S.
Therefore, even if dust or the like is generated in the first connecting portion 20 such as the speed reducer 22a in the first arm 11 of the transfer robot 10, the generated dust is prevented from flowing out from the first arm 11 into the work space S. Is done.

In addition, in the connecting portion 20 between the first arm 11 and the second arm 12, almost all of the load of the second arm 12 is supported by the rotating shaft body 23, and the rotating force that swings the second arm 12 is applied to the rotating shaft body. The signal is transmitted from the first arm 11 side to the second arm 12 side via 23. That is, the portion receiving the load of the second arm 12 or the rotational force for rotating the second arm 12 and the portion for sealing (sealing) are completely separated. That is, the load of the second arm 12 and the rotational force for rotating the second arm 12 are prevented from acting on the first sealing structure 30 including the bellows 41 and the magnetic sealing portion 50. With such a structure, deformation of the magnetic sealing part 50 is prevented, the holding state of the magnetic fluid 64 between the cylindrical member 51 and the magnetic seal unit 61 is stabilized, and torsional deformation of the bellows 41 is prevented. The sealed state is ensured.
Further, the rotating shaft body 23 may bend and deform under the load of the second arm 12. However, since the first sealing structure 30 has the bellows 41, the displacement due to the bending deformation of the rotating shaft body 23 is absorbed by the expansion / contraction deformation of the bellows 41, and the force due to the bending deformation is absorbed by the magnetic sealing portion 50. Does not work. That is, even if bending deformation occurs in the rotating shaft body 23, the hermeticity of the magnetic sealing part 50 is ensured.
Accordingly, dust generated in the first arm 11 of the transfer robot 10 is prevented from flowing out from the first arm 11 into the work space S.

As described above, the leg portion 10a and the first arm 11 and the second arm 12 and the third arm 13 are also connected to each other so as to be rotatable. The configuration is the same as that of the first connecting portion 20 that is the connecting portion of the first arm 11 and the second arm 12 described above. Therefore, the detailed description of the structure of these connecting portions is omitted here.

Further, the sealing structure according to the present invention is not limited to the structure of the above embodiment. Sealed structures modified within the scope of the present invention are included in the scope of the present invention.

For example, in the above-described embodiment, the bellows 41 is disposed so as to surround a part of the rotating shaft body 23 of the first connecting portion 20, but the first connecting portion (or the space in which the first connecting portion is disposed). What is necessary is just the arrangement | positioning which interrupts | blocks 20 and the working space S. FIG. The bellows 41 only needs to rotate integrally with the second arm 12. That is, the member to which the upper end portion of the bellows 41 is fixed is not limited to the second arm 12 and may be, for example, the rotary shaft body 23.

Further, it is preferable that the cylindrical member 51 is disposed so that the cylindrical axis of the outer peripheral surface 52a of the cylindrical cylindrical portion 52 and the axis of the rotary shaft body 23 coincide with each other. With such an arrangement, deformation of the bellows 41 is minimized. In the above embodiment, the bearing 66 is inserted between the cylindrical member 51 and the magnetic seal unit 61. However, a bearing structure such as a metal bearing structure may be used. Further, the cylindrical member 51 may not be an integral structure, and may be a structure in which both or one of the flange portions 53 can be attached to and detached from the cylindrical portion 52, for example.

Further, the fastening part (fixing part) between the bellows sealing part 40 and the magnetic sealing part 50 is not limited to the bolt fastening described above, and may be connected by welding, for example. The same applies to the fastening portion between the bellows sealing portion 40 and the magnetic sealing portion 50 and the first arm 11 and the second arm 12.

As for the synchronization mechanism, when the rotational resistance between the cylindrical member 51 of the magnetic sealing part 50 and the magnetic seal unit 61 is small, it is possible to adopt a structure that does not use the synchronization mechanism. It is preferable to prevent the torsional deformation of the bellows 41.
In the above embodiment, each of the first synchronization mechanism 70 has two protrusions 71 and two key groove parts 72, and the protrusion part 71 and the key groove part 72 have two engagement points in the circumferential direction. The number of the key groove portions 72 may be at least one, and the number of engagement portions may be at least one. And when providing a some synchronizing mechanism, arrange | positioning at equal intervals is preferable. For example, when two are provided, it is preferable that they are arranged opposite to each other with the rotary shaft 23 interposed therebetween, and when three are provided, it is preferably provided at 120-degree intervals so as to surround the rotary shaft 23.
Further, the protrusion 71 may be provided on the cylindrical member 51 and the key groove 72 may be provided on the rotating shaft body 23.
The first synchronization mechanism 70 may be any mechanism that synchronizes the rotation of the cylindrical member 51 and the rotation of the second arm 12. That is, the member on which the protrusion 71 is formed is not limited to the rotating shaft 23 as long as it is a member that rotates integrally with the second arm 12, and for example, the protrusion 71 may be formed on the second arm 12 itself.
Further, the protruding portion 71 may be in a state where both side surfaces of the protruding portion 71 are in contact with both side surfaces of the key groove portion 72, or may be in a state where only one side surface is in contact. In the case of a structure in which only one side is in contact, the phase difference when the gap distance between the side surface of the protrusion 71 and the side surface of the key groove 72 is maximized is set smaller than the allowable rotation angle of the bellows 41 for torsional deformation. Is done.

In the above embodiment, the magnetic seal 50 is fixed on the first arm 11 side (lower side) and the bellows 41 is arranged on the second arm 12 side (upper side). A structure in which the bellows 41 is disposed on the side and the magnetic sealing part 50 is disposed on the second arm 12 side may be employed. In this case, one end side of the bellows 41 is fixed to the first arm 11, and the other end side is fixed to the magnetic sealing part 50. For example, when the other end side of the bellows 41 is fixed to the cylindrical member 51 of the magnetic sealing part 50, the magnetic seal unit 61 of the magnetic sealing part 50 is fixed to the second arm 12.
More specifically, the rotating shaft body 23 is fixed to the second arm (in this case, the second arm is the first member) 12, the cylindrical member 51 is disposed inside the magnetic seal unit 61, and the cylindrical member 51 The cylindrical portion 52 has a convex outer peripheral surface, the circumferential portion 62 of the magnetic seal unit 61 is disposed opposite to the outer peripheral surface 52a of the cylindrical portion 52, and the outer peripheral surface 52a of the cylindrical portion 52 of the cylindrical member 51 is magnetically sealed. A magnetic fluid 64 is disposed between the magnetic pole member 63 of the circumferential portion 62 of the unit 61. A synchronization mechanism for fixing the tubular member 51 to the first arm (in this case, the first arm is the second member) 11 is provided. As this synchronization mechanism, for example, a support member provided inside the cylindrical member 51 in a state of being fixed to the casing 11a of the first arm 11 can be cited. When the cylindrical member 51 is supported by this support member, the force caused by the rotational resistance between the magnetic seal unit 61 and the cylindrical member 51 is received by the support member fixed to the first arm 11, and the bellows 41 torsional deformation is prevented.

In the above embodiment, the first arm 11 is a base-side member and the second arm 12 is a rotation-side member, but the reverse is also possible. Further, in the above embodiment, the cylindrical portion 52 of the cylindrical member 51 is surrounded by the circumferential portion 62 of the magnetic seal unit 61, and the cylindrical outer surface of the cylindrical portion 52 is external to the magnetic seal unit 61. The surface (outer surface) of the circumferential portion 62 is oriented inward with respect to the cylindrical member 51 in the orientation, but the opposite arrangement may be employed. In other words, the surface (outer surface) of the circumferential portion 62 may be directed outward toward the cylindrical member 51, and the cylindrical surface (outer surface) of the cylindrical portion 52 may be disposed inward with respect to the magnetic seal unit 61.

Claims

A sealing structure that seals a connecting portion between the first member and the second member connected to the first member via a rotating shaft;
The said sealing structure has a magnetic sealing part by a magnetic fluid, and a bellows sealing part comprised with the bellows, The sealing structure characterized by the above-mentioned.
The bellows of the bellows sealing part has one end fixed to the second member and the other end fixed to the magnetic sealing part.
The magnetic sealing part includes one magnetic seal member to which the other end side of the bellows is fixed, and the other magnetic seal member fixed to the first member side,
The one magnetic seal member includes a cylindrical portion disposed so that the other magnetic seal member is opposed to the first magnetic seal member,
The other magnetic seal member includes a circumferential portion disposed to face the cylindrical portion of the one magnetic seal member, and the circumferential portion of the cylindrical portion of the one magnetic seal member and the circumference of the other magnetic seal member The sealed structure according to claim 1, wherein the magnetic fluid is disposed between the first portion and the second portion.
The hermetic structure according to claim 2, further comprising a rotation synchronization mechanism that synchronizes the rotation of the one magnetic seal member and the rotation of the second member.
The rotating shaft is fixed to the second member;
The one magnetic seal member is disposed inside the other magnetic seal member,
The cylindrical portion of the one magnetic seal member includes an outer peripheral surface made of a magnetic material,
The circumferential portion of the other magnetic seal member includes a magnetic pole member disposed opposite to the outer peripheral surface of the cylindrical portion,
The hermetic structure according to claim 2 or 3, wherein a magnetic fluid is disposed between an outer peripheral surface of the cylindrical portion of the one magnetic seal member and a magnetic pole member at a circumferential portion of the other magnetic seal member.
The sealing structure according to claim 4, wherein the rotation synchronization mechanism is provided between the rotating shaft body and the one magnetic seal member.
The rotation synchronization mechanism includes a protrusion formed on an outer peripheral surface of the rotary shaft body, and a groove formed on an inner peripheral surface of the one magnetic seal member and engaged with the protrusion. Item 6. The sealed structure according to Item 5.
The sealing structure according to claim 6, wherein at least one engaging portion is provided by the protruding portion and the groove portion.
The rotating shaft is fixed to the first member;
The one magnetic seal member is disposed inside the other magnetic seal member,
The cylindrical portion of the one magnetic seal member includes an outer peripheral surface made of a magnetic material,
The circumferential portion of the other magnetic seal member includes a magnetic pole member disposed opposite to the outer peripheral surface of the cylindrical portion,
The sealed structure according to claim 3, wherein a magnetic fluid is disposed between the outer peripheral surface of the cylindrical portion of the one magnetic seal member and the magnetic pole member of the circumferential portion of the other magnetic seal member.
The sealing structure according to claim 8, further comprising a synchronization mechanism for fixing the one magnetic seal member to the second member.
The sealing structure according to any one of claims 2 to 9, wherein the other magnetic seal member and the one magnetic seal member are rotatably engaged via a bearing member.
11. The hermetic coupling portion according to claim 2, further comprising a sealing member that is mounted with a detachable elastic member between the one magnetic sealing member and the bellows. The sealed structure described in 1.
A transport robot including a joint portion that rotatably connects a base side member and a rotation side member,
The joint portion includes a rotating shaft that connects the base side member and the rotating side member so as to be relatively rotatable,
A sealing structure for sealing the joint part;
The transporting robot is characterized in that the sealing structure includes a magnetic sealing part made of a magnetic fluid and a bellows sealing part made of a bellows.
A transport robot including a joint portion that rotatably connects a base side member and a rotation side member,
The base side member is one of the first member and the second member,
The rotation side member is the remaining other of the first member and the second member,
The joint portion includes the rotating shaft body that connects the base side member and the rotating side member so as to be relatively rotatable,
A sealing structure for sealing the joint part;
The sealing structure has a magnetic sealing portion made of magnetic fluid and a bellows sealing portion made of a bellows.
The transfer robot according to any one of claims 1 to 11, wherein the sealing structure is a sealing structure.