Sealing device

Abstract

The present invention provides a sealing device, which can recycle a small amount of lubricating fluid through gravity to extend the life of a mechanical seal, and has a simple and compact structure. The sealing device includes: a housing; and a mechanical seal, which seals the lubricating fluid through a sliding portion, wherein the sliding portion is formed by a rotating ring fixed to the outer peripheral surface of a rotating shaft and a stationary ring fixed to the inner peripheral surface of the housing, which are opposed and in relative contact in the axial direction, and the housing includes: a recovery groove, which is formed on the outer peripheral surface of the housing and is used to recover the lubricating fluid scattered from the outside of the housing; and at least one inflow path, which runs from the recovery groove to the inner peripheral surface of the housing and has an opening connected to the recovery groove upward in the direction of gravity.

Description

Technical Field

[0001] The present invention relates to sealing devices. Background Art

[0002] Conventionally, the reducer integrated with the drive motor has a structure in which the motor drive shaft of the drive motor is integrally formed with the reducer input shaft of the reducer. The drive motor usually rotates at high speed, and the sealing device such as the mechanical seal is also in a high peripheral speed environment.

[0003] In this reducer, Figure 8 The following device is proposed: the gear shaft (not shown) of the speed reducer 3 is connected to the drive shaft 6 of the screw pump 5 for fuel delivery, and when the pump is driven, the fuel is sucked from the suction port 9 connected to the fuel tank and sprayed from the discharge port 10 to the engine (for example, refer to Patent Document 1). In the device of Patent Document 1, the drive shaft 6 between the discharge port 10 and the speed reducer 3 is provided with a mechanical seal 18 including two opposed double seals 20 and 21.

[0004] (Prior art literature)

[0005] (Patent Document)

[0006] Patent document 1: Japanese Utility Model Publication No. 62-160788. Summary of the invention

[0007] (Problem to be solved by the invention)

[0008] However, in the device of Patent Document 1, the reducer side seal portion 21 and the bearing 22 of the mechanical seal 18 are lubricated with the lubricating oil of the reducer 3. This structure requires the auxiliary pump 11 to supply lubricating oil, so the number of parts increases, and the entire device becomes complicated and large.

[0009] The present invention has been developed in view of the above circumstances, and its object is to provide a sealing device which has a simpler structure and is smaller than conventional ones, and which can extend the life of a mechanical seal with a small amount of lubricating fluid.

[0010] (Solutions used to solve problems)

[0011] In order to achieve the above-mentioned purpose, the sealing device of the present invention is characterized in that it includes: a housing; and a mechanical seal, which seals the lubricating fluid through a sliding portion, and the sliding portion is formed by a rotating ring fixed on the outer peripheral surface of the rotating shaft and a stationary ring fixed on the inner peripheral surface of the housing, which are opposed and contacted in the axial direction, and the housing includes: a recovery groove, which is formed on the outer peripheral surface of the housing and is used to recover the lubricating fluid scattered from the outside of the recovery groove; and at least one inflow path, which passes through from the outer peripheral surface of the housing to the inner peripheral surface of the housing and has an opening portion connected to the recovery groove upward in the direction of gravity, so that the lubricating fluid recovered by the recovery groove flows into the sliding portion of the mechanical seal.

[0012] According to the sealing device described in Technical Solution 1, preferably, the recovery groove is roughly in the shape of a frustum.

[0013] According to the sealing device of claim 1, preferably, the recovery groove, the opening, and the inflow path are formed on the outer peripheral surface of the housing at positions within 45 degrees on both sides in the circumferential direction from the vertex position in the gravity direction.

[0014] According to the sealing device described in Technical Solution 3, preferably, the shell includes a plurality of the inflow paths and the recovery grooves formed with the openings, and the shell has a connecting groove for connecting the plurality of the recovery grooves to each other.

[0015] In addition, the sealing device of the present invention is characterized in that it includes: a housing; and a mechanical seal that seals the lubricating fluid through a sliding portion, the sliding portion being formed by a rotating ring fixed to the outer circumferential surface of the rotating shaft and a stationary ring fixed to the inner circumferential surface of the housing, which are opposed and relatively contacted in the axial direction, the housing including: a recovery groove, which is formed on the outer circumferential surface of the housing and is used to recover the lubricating fluid scattered from the outside of the housing; and a plurality of inflow paths, which penetrate from the recovery groove to the inner circumferential surface of the housing and have an opening portion connected to the recovery groove upward in the gravity direction, so that the lubricating fluid recovered by the recovery groove flows into the sliding portion of the mechanical seal, the recovery groove including: a recovery portion, whose radial cross section is roughly "V"-shaped or whose radial cross section is roughly "U"-shaped; and an inclined portion, which is connected to the recovery portion in the circumferential direction and extends in the circumferential direction, and is inclined from the upper side to the bottom of the recovery portion in the gravity direction, and the opening portion is arranged at the bottom of the recovery portion.

[0016] According to the sealing device described in Technical Solution 5, preferably, the opening portion is arranged at an intersection position where the bottom of the recovery portion and the inclined portion intersect.

[0017] According to the sealing device described in any one of technical solutions 1 to 6, preferably, a rib protruding from the outer peripheral surface of the shell is formed on the outer peripheral surface of the shell, and the rib is erected at the end of the recovery groove or at a position close to the end in such a manner that the inclined portion of the recovery groove is clamped between the opening portion and the rib.

[0018] According to the sealing device described in Technical Solution 7, preferably, the sealing device is used to seal the lubricating fluid of the reducer.

[0019] (Effects of the Invention)

[0020] According to the present invention, a sealing device can be realized which has a simpler structure and is smaller than that of the related art and which can extend the service life of the sealing device with a small amount of lubricating fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic cross-sectional view showing the overall structure of a sealing system according to an embodiment of the present invention.

[0022] Figure 2 It is a partially enlarged cross-sectional view showing the structure of the sealing device according to the first embodiment of the present invention.

[0023] Figure 3 It is a partially enlarged cross-sectional view showing the structure of a pipe portion of a casing according to the first embodiment of the present invention.

[0024] Figure 4 It is a partially enlarged perspective view showing the structure of a pipe portion of a casing according to the first embodiment of the present invention.

[0025] Figure 5 It is a partially enlarged cross-sectional view showing the structure of a pipe portion of a casing according to a third embodiment of the present invention.

[0026] Figure 6 It is a partially enlarged perspective view showing the structure of a pipe portion of a casing according to a third embodiment of the present invention.

[0027] Figure 7 It is a partially enlarged cross-sectional view showing the structure of a sealing device according to another embodiment.

[0028] Figure 8 It is a cross-sectional view showing the structure of a conventional sealing device. DETAILED DESCRIPTION

[0029] Summary of Implementation Methods

[0030] First, a typical embodiment of the invention disclosed in this application will be described in outline. In the following description, as an example, reference numerals on the drawings corresponding to the components of the invention are described in parentheses.

[0031] [1] A sealing device (300) according to a typical embodiment of the present invention comprises: a housing (110); and a mechanical seal (310) for sealing a lubricating fluid by means of a sliding portion (315), wherein the sliding portion (315) is formed by a rotating ring (312) fixed to an outer peripheral surface (103g) of a rotating shaft (101) and a stationary ring (311) fixed to an inner peripheral surface (111na, 111nb) of the housing (110) facing each other and in relative contact in an axial direction, wherein the housing (110) comprises: a recovery groove (127, 137, 138, 140) formed on the outer peripheral surface (103g) of the housing (110), and used to recover lubricating fluid scattered from the outside of the housing (110); and at least one inflow path (120, 120a, 120b), which penetrates from the recovery groove (127, 137, 138, 140) to the inner peripheral surface (111na, 111nb) of the housing (110), and has an opening (120h, 120ah, 120bh) connected to the recovery groove (127, 137, 138, 140) upward in the gravity direction, and allows the lubricating fluid recovered by the recovery groove (127, 137, 138, 140) to flow to the sliding part (315) of the mechanical seal (310).

[0032] [2] In the sealing device (300) of [1], the recovery groove (127, 137, 138, 140) is substantially in the shape of a frustum.

[0033] [3] In the sealing device (300) of [2], the recovery groove (127, 137, 138, 140), the opening (120h, 120ah, 120bh), and the inflow path (120, 120a, 120b) are formed at a position within 45 degrees on both sides of the circumference from the vertex (111gp) in the gravity direction of the outer peripheral surface (111g) of the shell (110).

[0034] [4] In the sealing device (300) of [3], the shell (110) includes a plurality of the inflow paths (120, 120a, 120b) formed with the openings (120h, 120ah, 120bh) and the recovery grooves (137, 138, 140), and the shell (110) has a connecting groove (130) for connecting the plurality of recovery grooves to each other.

[0035] [5] In addition, a sealing device (300) according to a representative embodiment of the present invention comprises: a housing (110); and a mechanical seal (310) which seals a lubricating fluid by means of a sliding portion (315), wherein the sliding portion (315) is formed by a rotating ring (312) fixed to an outer peripheral surface (103g) of a rotating shaft (101) and a stationary ring (311) fixed to an inner peripheral surface (111na, 111nb) of the housing (110) which are opposed to each other in an axial direction and in relative contact with each other, and the housing (110) comprises: a recovery groove (140) which is formed on an outer peripheral surface (103g) of the housing (110) and is used to recover the lubricating fluid scattered from the outside of the housing (110); and a plurality of inflow paths (120a, 120b) which extend from the recovery groove (140) to the housing (110). The inner circumferential surface (111na, 111nb) of the mechanical seal (310) is provided with an opening (120ah, 120bh) connected upward to the recovery groove (140) in the direction of gravity, and the lubricating fluid recovered by the recovery groove (140) flows to the sliding portion (315) of the mechanical seal (310), wherein the recovery groove (140) includes: a recovery portion (149) having a substantially "V"-shaped radial cross section or a substantially "U"-shaped radial cross section; and an inclined portion (148a, 148b) connected to the recovery portion (149) in the circumferential direction and extending in the circumferential direction, and inclined from the upper side to the bottom (149i) of the recovery portion (149) in the direction of gravity, and the opening (120ah, 120bh) is arranged at the bottom (149i) of the recovery portion (149).

[0036] [6] In the sealing device of [5], the opening (120ah, 120bh) is provided at an intersection where the bottom (149i) of the recovery portion (149) and the inclined portions (148a, 148b) intersect.

[0037] [7] In the sealing device of [5] or [6], ribs (118a, 118b) protruding from the outer peripheral surface (111g) of the shell (110) of the sealing device (300) are formed, and the ribs (118a, 118b) are uprightly arranged at the end of the recovery groove (140) or at a position close to the recovery groove (140) in a manner that the inclined portion (148a, 148b) of the recovery groove (140) is clamped between the opening portion (120ah, 120bh) and the ribs (118a, 118b).

[0038] [8] In the sealing device of [1] or [5], the sealing device (300) is used to seal the lubricating fluid of the reducer (200).

[0039] <Implementation Method>

[0040] Next, embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 2 is a schematic cross-sectional view showing the overall structure of a sealing system 1 according to an embodiment of the present invention. In addition, although the present invention includes the first to third embodiments, the sealing system 1 is common to all the embodiments.

[0041] The sealing system 1 includes a driving motor 100, a reducer 200, and a sealing device 300 disposed between the driving motor 100 and the reducer 200. The motor driving shaft 101 of the driving motor 100 and the reducer input shaft 201 of the reducer 200 are an integrated structure.

[0042] <First embodiment>

[0043] Figure 2 It is a partially enlarged cross-sectional view showing the structure of the sealing device according to the first embodiment of the present invention.

[0044] Figure 3 It is a partially enlarged cross-sectional view showing the structure of a pipe portion of a casing according to the first embodiment of the present invention.

[0045] Figure 4 It is a partially enlarged perspective view showing the structure of a pipe portion of a casing according to the first embodiment of the present invention.

[0046] Here, for the sake of convenience, the arrow a direction along the axis X is set as the left side or the reducer side, and the arrow b direction is set as the right side or the drive motor side. In addition, the arrow c direction close to the axis X is set as the radial inner peripheral side, and the arrow d direction away from the axis X is set as the radial outer peripheral side. Figure 1 In FIG. 1 , the direction of arrow e is set as the upper side, and the direction of arrow f is set as the lower side. The upper side and the lower side referred to here refer to the upper side and the lower side in the direction of gravity.

[0047] like Figure 1 to Figure 3 As shown, the sealing device 300 according to the first embodiment of the present invention is disposed between the drive motor 100 and the speed reducer 200. The sealing device 300 is composed of a pipe portion 111 of a housing 110 of the drive motor 100, which will be described later, and a mechanical seal 310.

[0048] The driving motor 100 includes a housing 110 covering the entire motor (not shown), and the reducer 200 includes a housing 210 having a reduction mechanism (not shown) inside, and the side 110s of the housing 110 of the driving motor 100 and the side 210s of the housing 210 of the reducer 200 are fixed in a state where the side 110s of the housing 110 of the driving motor 100 and the side 210s of the housing 210 of the reducer 200 are in contact with each other.

[0049] A cylindrical pipe 111 is provided on a side surface 110s of the housing 110 of the drive motor 100 and protrudes toward the speed reducer in the direction of arrow a along the axis X (hereinafter referred to as “axis X direction”). The pipe 111 is integrated with the housing 110 and becomes a part of the housing 110.

[0050] The tube 111 of the housing 110 has a cylindrical cross-section with an outer diameter gradually decreasing from the drive motor side to the reducer side. That is, the tube 111 has a tapered outer peripheral surface 111g that gradually becomes thinner from the drive motor side to the reducer side. The housing 110 has an axial hole communicating with the tube 111.

[0051] The inner peripheral surface of the shaft hole formed on the housing 110 has a step portion 115 formed thereon for retaining the bearing (hereinafter referred to as the "motor side bearing") 113 on the driving motor side. The outer ring 113g of the motor side bearing 113 is fixed to the step portion 115 in an interlocking state.

[0052] The motor side bearing 113 includes an outer ring 113g, rolling elements 113b, and an inner ring 113n, and the motor drive shaft 101 of the drive motor 100 is fixed integrally to the inner ring 113n. That is, the motor drive shaft 101 rotates integrally with the inner ring 113n of the motor side bearing 113.

[0053] The motor drive shaft 101 includes a cylindrical portion 102 and a cylindrical portion 103, wherein the cylindrical portion 103 is formed at the front end portion of the cylindrical portion 102 on the reducer side. The cylindrical portion 102 of the motor drive shaft 101 is pivotally supported by a motor-side bearing 113. The outer diameter of the cylindrical portion 103 of the motor drive shaft 101 is slightly smaller than that of the cylindrical portion 1021. The cylindrical portion 103 has an inner circumferential spline portion processed with grooves on its inner circumferential surface.

[0054] A step portion 125 is formed on the inner circumferential surface 111na of the front end portion of the reducer side of the tube portion 111, which is used to hold the reducer side bearing (hereinafter referred to as the "reducer side bearing") 123, and the outer ring 123g of the reducer side bearing 123 is fixed to the step portion 125 in an interlocking state.

[0055] The reducer side bearing 123 includes an outer ring 123g, rolling elements 123b, and an inner ring 123n, and the reducer input shaft 201 of the reducer 200 is fixed integrally to the inner ring 123n. That is, the reducer input shaft 201 and the inner ring 123n of the reducer side bearing 123 rotate integrally.

[0056] The reducer input shaft 201 includes a large diameter cylindrical portion 202 having a large outer diameter and a small diameter cylindrical portion 203 having a small outer diameter. The small diameter cylindrical portion 203 is formed at the front end portion of the large diameter cylindrical portion 202 and has an outer diameter smaller than the large diameter cylindrical portion 202. The large diameter cylindrical portion 202 of the reducer input shaft 201 is pivotally supported by the reducer side bearing 123.

[0057] The outer diameter of the small diameter cylindrical portion 203 of the speed reducer input shaft 201 is the same as the inner diameter of the cylindrical portion 103 of the motor drive shaft 101 , and the outer peripheral surface of the small diameter cylindrical portion 203 has a grooved outer peripheral spline portion.

[0058] That is, the inner circumferential spline portion formed on the inner circumferential surface of the cylindrical portion 103 of the motor drive shaft 101 engages with the outer circumferential spline portion formed on the outer circumferential surface of the small diameter cylindrical portion 203 of the reducer input shaft 201, and the rotation (driving force) of the motor drive shaft 101 is transmitted to the reducer 200 via the reducer input shaft 201.

[0059] A mechanical seal 310 is disposed between the inner peripheral surface 111nb of the tube portion 111 of the housing 110 on the drive motor side and the outer peripheral surface 103g of the cylindrical portion 103 of the motor drive shaft 101, and between the inner peripheral surface 111na of the tube portion 111 on the reducer side and the outer peripheral surface 103g of the cylindrical portion 103 of the motor drive shaft 101. In addition, the mechanical seal 310 is disposed between the motor side bearing 113 and the reducer side bearing 123 in the axis X direction.

[0060] That is, an annular space on the drive motor side (hereinafter referred to as "motor side space") 114 is formed between the inner peripheral surface 111nb on the drive motor side of the tube portion 111 and the outer peripheral surface 103g of the cylindrical portion 103 of the motor drive shaft 101, that is, between the motor side bearing 113 and the mechanical seal 310. In the motor side space 114, the sealed fluid of the drive motor 100 is sealed.

[0061] In addition, an annular space on the reducer side (hereinafter referred to as "reducer side space") 124 is formed between the reducer side inner circumferential surface 111na of the tube portion 111 and the outer circumferential surface 103g of the cylindrical portion 103 of the motor drive shaft 101, that is, between the reducer side bearing 123 and the mechanical seal 310. The lubricating fluid of the reducer 200 can be supplied to the reducer side space 124.

[0062] The mechanical seal 310 includes a stationary ring 311 and a rotating ring 312, and the stationary ring 311 and the rotating ring 312 are in contact with each other in a relatively slidable manner. That is, the mechanical seal 310 prevents the sealed fluid from leaking from the motor side space 114 to the reducer side space 124 and prevents the lubricating fluid from leaking from the reducer side space 124 to the motor side space 114 through the sliding of the stationary ring 311 and the rotating ring 312. Here, the contact portion between the stationary ring 311 and the rotating ring 312 is a sliding portion 315.

[0063] The stationary ring 311 is fixed to the inner peripheral surface 111nb of the pipe portion 111 of the housing 110 of the drive motor 100 by a fixing member (not shown) and is arranged on the drive motor side in the axis X direction.

[0064] The stationary ring 311 is a sealing ring composed of a ring-shaped member with a rectangular cross section, and is formed of, for example, silicon carbide, ceramics, superhard alloy, carbon material, etc. The stationary ring 311 does not contact the cylindrical portion 103 of the motor drive shaft 101, and cannot rotate relative to the motor drive shaft 101. The stationary ring 311 has a sealing surface, and the sealing surface is used to form a sliding portion 315, and the sliding portion 315 is opposite to and in contact with the rotating ring 312 in the axis X direction.

[0065] The rotating ring 312 is integrally mounted on the outer peripheral surface 103g of the cylindrical portion 103 of the motor drive shaft 101 through a fixing member not shown. The rotating ring 312 is arranged at a position closer to the reducer side than the stationary ring 311 in the axis X direction. That is, the rotating ring 312 is arranged closer to the reducer side than the stationary ring 311, and rotates integrally with the cylindrical portion 103 of the motor drive shaft 101.

[0066] The rotating ring 312 is a mating ring composed of a ring-shaped member with a rectangular cross section, and is formed of silicon carbide, ceramics, superhard alloy, carbon material, etc., similar to the stationary ring 311. The rotating ring 312 has a sealing surface for forming a sliding portion 315, which is opposite to and in contact with the stationary ring 311.

[0067] When the motor driving shaft 101 of the driving motor 100 rotates in a state where the sealing surface of the stationary ring 311 contacts the sealing surface of the rotating ring 312 , a sliding portion 315 is formed between the stationary ring 311 and the rotating ring 312 .

[0068] As described above, the mechanical seal 310 forms the sliding portion 315 between the stationary ring 311 and the rotating ring 312 , thereby sealing the space between the motor side space 114 and the speed reducer side space 124 .

[0069] Here, if Figure 1 As shown in FIG. 1 , the sliding portion 315 of the mechanical seal 310 is arranged on the reducer side in the direction of the axis X. Specifically, the sliding portion 315 of the mechanical seal 310 is covered by the pipe portion 111 of the housing 110, but Figure 1 When viewed from the upper side in the gravity direction (direction of arrow e), it is located in the space of the housing 210 of the reducer 200.

[0070] The tube portion 111 of the housing 110 is an annular cylindrical portion. Figure 3As shown in (A), the tube portion 111 has an inflow path 120, which extends linearly from a recovery groove 127 described later toward the rotation axis X and penetrates the inner circumferential surface 111na of the tube portion 111. The recovery groove 127 is arranged at a position on the lower side that is inclined about 45 degrees counterclockwise in the figure from the position of the highest vertex 111gp on the upper side of the gravity direction of the outer circumferential surface 111g (in the direction of arrow e).

[0071] This is because, as the inflow path 120 extends counterclockwise in the figure from the position of the vertex 111gp, the lubricating fluid is likely to flow directly into the outflow path 122 instead of flowing from the inflow path 120 to the sliding portion 315. Therefore, when the tube portion 111 is arranged in the inflow path 120, it is preferably set to a range to a position that deviates from the position of the vertex 111gp by about 45 degrees.

[0072] The inflow path 120 has a predetermined inner diameter and connects the outer peripheral space of the tube 111 with the reducer side space 124. The outer peripheral space of the tube 111 is the space on the outer peripheral side of the outer peripheral surface 111g of the tube 111, but is always the inner space of the housing 210 of the reducer 200.

[0073] The inflow path 120 is formed of a linear through hole, and its inner diameter can be arbitrarily determined in consideration of the viscosity of the lubricating fluid of the speed reducer 200 when passing through the inflow path 120. That is, the flowability of the lubricating fluid when flowing through the inflow path 120 should be considered.

[0074] In addition, the inflow path 120 is provided at a position facing the sliding portion 315 of the mechanical seal 310 in the radial direction. Figure 3 The inflow path 120 is configured to match the direction in which the lubricating fluid scatters, and when the lubricating fluid scatters in the XY plane, for example, toward the first quadrant, the inflow path 120 can be configured in the first quadrant.

[0075] The inflow path 120 has an opening 120h facing upward in the gravity direction relative to the end of the outer peripheral side of the tube 111. The opening 120h is an opening that becomes an inlet portion when the lubricating fluid of the reducer 200 passes through the inflow path 120, and the scattered lubricating fluid flows into the inflow path 120 when falling due to gravity.

[0076] In addition, the inflow path 120 has an opening 120h and is connected to a recovery groove 127. The recovery groove 127 is formed on the outer peripheral surface 111g of the tube portion 111 of the housing 110, and guides the lubricating fluid scattered from the outside and flowing on the outer peripheral surface 111g of the tube portion 111 to the opening 120h of the inflow path 120 and recovers it.

[0077] The recovery groove 127 is in the shape of a truncated cone. However, the shape of the recovery groove 127 is not limited thereto, and the shape of the recovery groove 127 may also be a truncated cone shape, such as a quadrangular truncated cone shape or an elliptical truncated cone shape. Here, the generatrix of the truncated cone is not necessarily axisymmetric, and the generatrix may be inclined toward the opening 120h, and the generatrix may also be a curve.

[0078] like Figure 3 As shown in (B), the recovery groove 127 has a disk surface 127ab which is circular when viewed from above. The disk surface 127ab with a conical cross section has a smooth surface that divides the recovery groove 127. The disk surface 127ab is composed of an inclined surface (hereinafter referred to as the "first inclined surface") 127a and an inclined surface (hereinafter referred to as the "second inclined surface") 127b in the entire inclined surface inclined from the upper side of the gravity direction toward the opening 120h, wherein the first inclined surface 127a is the upper half close to the vertex 111gp in the gravity direction, and the second inclined surface 127b is the lower half on the side opposite to the vertex 111gp in the gravity direction.

[0079] The first inclined surface 127a of the recovery groove 127 is inclined from the upper side in the gravity direction toward the opening 120h at the outer peripheral surface 111g of the tube portion 111 of the housing 110, and connects the opening 120h to the outer peripheral surface 111g of the tube portion 111 of the housing 110. The second inclined surface 127b of the recovery groove 127 is located on the opposite side of the first inclined surface 127a in the circumferential direction of the outer peripheral surface 111g of the tube portion 111 of the housing 110.

[0080] On the other hand, Figure 2 As shown, the tube portion 111 of the housing 110 has a linear outflow path 122 that passes through between the lowest point position of the lower side (arrow f direction) of the outer peripheral surface 111g in the gravity direction and the inner peripheral surface 111na of the tube portion 111 along the rotation axis X. At this time, the outflow path 122 also connects the outer peripheral side space of the tube portion 111 with the reducer side space 124.

[0081] The outflow path 122 of the tube portion 111 is also provided near the mechanical seal 310 in the direction of the axis X. Since the outflow path 122 is only used to discharge the lubricating fluid after cooling and lubricating the mechanical seal 310, it is not necessary to be provided at a position opposite to the mechanical seal 310 in the radial direction. However, the present invention is not limited thereto, and the outflow path 122 may also be provided at a position opposite to the sliding portion 315 of the mechanical seal 310 in the radial direction. In this case, the circulation of the lubricating fluid becomes better.

[0082] The inner diameter of the outflow path 122 is larger than the inner diameter of the inflow path 120. However, this is not limited to this, and the inner diameter of the inflow path 120 may be substantially the same as the inner diameter of the outflow path 122. Figure 2 In, it is expressed Figure 3 A cross-sectional view of the inflow path 120 and the outflow path 122 when they are cut.

[0083] The tube 111 has a disc-shaped flange 116 extending from the outer peripheral surface 111g in the outer peripheral direction (arrow d direction) perpendicular to the axis X direction between the mechanical seal 310 and the motor-side bearing 113 in the axis X direction. The flange 116 abuts against the side surface 110s ( Figure 1 ). In addition, Figure 1 In the figure, the flange portion 116 is omitted.

[0084] Two ribs 118a and 118b having a substantially triangular shape in side view are integrally fixed to the flange portion 116. The ribs 118a and 118b are integrally fixed not only to the flange portion 116 but also to the outer peripheral surface 111g of the pipe portion 111.

[0085] One of the ribs 118a is disposed at the position of the vertex 111gp in the gravity direction. However, the present invention is not limited thereto, and one of the ribs 118a may be disposed at a position adjacent to or close to the first inclined surface 127a of the recovery groove 127. In addition, close to means a range in which the lubricating fluid that hits the rib 118a can be recovered by the recovery groove 127.

[0086] The other rib 118b is arranged at a position deviated from one of the ribs 118a in the counterclockwise direction of the figure by a predetermined angle (in this case, more than 45 degrees), that is, at a position adjacent to the second inclined surface 127b of the recovery groove 127. Not limited to this, the other rib 118b can also be arranged at a position close to the second inclined surface 127b of the recovery groove 127.

[0087] The angle interval between the two ribs 118a and 118b is arbitrary as long as they can at least sandwich the inflow path 120. In particular, the rib 118a disposed at the position of the vertex 111gp on the upper side in the gravity direction is erected so as to sandwich the first inclined surface 127a of the recovery groove 127 between the opening 120h of the inflow path 120 and the rib 118a.

[0088] The following describes the usage of the sealing device 300 having the above-mentioned structure. Figure 1 As shown, in the sealing device 300 involved in the first embodiment, if the lubricating fluid is stirred and gathered by the gear (not shown) fixed to the reducer input shaft 201 of the reducer 200, after the lubricating fluid hits one of the ribs 118a of the tube portion 111, the lubricating fluid falls vertically along the surface of the rib 118a and flows downward to the outer peripheral surface 111g of the tube portion 111.

[0089] The lubricating fluid is received by the first inclined surface 127a of the recovery groove 127 along the outer peripheral surface 111g of the tube portion 111. Since the recovery groove 127 has a larger area for receiving the lubricating fluid through the first inclined surface 127a, the recovery efficiency of the scattered lubricating fluid can be improved. Then, the lubricating fluid flows from the first inclined surface 127a of the recovery groove 127 into the opening 120h and flows into the speed reducer side space 124 from the inflow path 120, thereby cooling the sliding portion 315 of the mechanical seal 310 and lubricating it.

[0090] On the other hand, the lubricating fluid that hits the other rib 118b of the tube portion 111 falls vertically along the surface of the rib 118b, and is thus received by the second inclined surface 127b of the recovery groove 127. Since the recovery groove 127 has a larger area for receiving the lubricating fluid through the second inclined surface 127b, the recovery efficiency of the scattered lubricating fluid can be improved.

[0091] Then, the lubricating fluid flows from the second inclined surface 127 b of the recovery groove 127 into the opening 120 h and flows from the inflow path 120 into the speed reducer-side space 124 , thereby cooling and lubricating the sliding portion 315 of the mechanical seal 310 .

[0092] After that, the lubricating fluid drips downward (in the direction of arrow f) along the inner peripheral surface 111na of the tube portion 111 in the reducer side space 124, and is discharged into the housing 210 of the reducer 200 through the outflow path 122. In addition, after being discharged into the reducer 200, the lubricating fluid is stirred and gathered again by the gears, and is used again for cooling and lubricating the mechanical seal 310.

[0093] According to the above configuration, the sealing device 300 is provided with the inflow path 120 and the outflow path 122 at positions facing the sliding portion 315 of the mechanical seal 310 with respect to the outer peripheral surface 111 g of the tube portion 111 of the housing 110 .

[0094] Thus, the sealing device 300 allows the lubricating fluid gathered by the gears of the reducer 200 to flow in from the opening 120h of the inflow path 120, thereby directly and effectively cooling and lubricating the sliding portion 315 of the mechanical seal 310, and at the same time, the lubricating fluid can lubricate the interior of the housing 210 of the reducer 200.

[0095] As described above, the sealing device 300 circulates the lubricating fluid of the reducer 200 through the inflow path 120 and the outflow path 122 of the tube portion 111 , thereby improving the cooling effect and lubricating effect on the sliding portion 315 of the mechanical seal 310 with a small amount of lubricating fluid.

[0096] In addition, the sealing device 300 supplies the lubricating fluid to the reducer side space 124 via the inflow path 120, and discharges the lubricating fluid from the reducer side space 124 via the outflow path 122, thereby realizing continuous circulation. Therefore, the lubricating fluid will not be retained in the reducer side space 124, thereby providing a high-cleanliness lubrication environment without residual foreign matter in the reducer side space 124.

[0097] <Second embodiment>

[0098] Figure 4 FIG. 2 is a partially enlarged cross-sectional view showing the structure of a sealing device according to a second embodiment of the present invention. Figure 4 In the present invention, the same reference numerals are used to denote the configuration and corresponding parts as those in the first embodiment, and the description thereof will be omitted.

[0099] like Figure 4 As shown in (A), the sealing device 300 of the second embodiment is different from the first embodiment in the configuration and number of inflow paths 120a and 120b provided in the tube portion 111 of the housing 110, the recovery grooves 137 and 138, and the connecting groove 130.

[0100] At this time, one inflow path 120a and the other inflow path 120b are formed at a 45 degree interval with the position of the vertex 111gp in the gravity direction of the outer peripheral surface 111g of the tube part 111 as the center. One inflow path 120a and the other inflow path 120b penetrate from one recovery groove 137 and the other recovery groove 138 to the inner peripheral surface 111na of the tube part 111 of the housing 110, and have openings 120ah and 120bh similarly to the first embodiment.

[0101] At this time, assuming that the XY plane is used, one inflow path 120a is arranged in the first quadrant, and the other inflow path 120b is arranged in the second quadrant. In addition, the one inflow path 120a and the other inflow path 120b have the same structure and are arranged symmetrically around the position of the uppermost vertex 111gp.

[0102] In addition, one recovery groove 137 is provided in one inflow path 120a, and another recovery groove 138 is provided in the other inflow path 120b. Similar to the first embodiment, the one recovery groove 137 and the other recovery groove 138 guide the lubricating fluid dispersed to the outside to the opening 120ah of the one inflow path 120a and the opening 120bh of the other inflow path 120b, respectively, and recover it.

[0103] One of the recovery grooves 137 and the other recovery groove 138 is in the shape of a truncated cone similar to the first embodiment. However, it is not limited thereto, and the shape of one of the recovery grooves 137 and the other recovery groove 138 may also be a truncated cone shape, such as a quadrangular truncated cone shape or an elliptical truncated cone shape. Here, the generatrix of the truncated cone does not necessarily have to be axially symmetrical, and the generatrix may be inclined toward one of the openings 120ah and the other opening 120bh, or the generatrix may be a curve.

[0104] like Figure 4 As shown in (B), one of the recovery tanks 137 (arranged in the first quadrant) has a disk surface 137ab formed by a smooth surface in a circular shape when viewed from above. The disk surface 137ab includes a first inclined surface 137a and a second inclined surface 137b, wherein the first inclined surface 137a is the upper half close to the vertex 111gp in the direction of gravity, and the second inclined surface 137b is the lower half on the side opposite to the vertex 111gp in the direction of gravity.

[0105] The disk surface 137ab is composed of an inclined surface (hereinafter referred to as the "first inclined surface") 137a and an inclined surface (hereinafter referred to as the "second inclined surface") 137b in the overall inclined surface that is inclined from the upper side of the opening portion 120ah in the direction of gravity, wherein the first inclined surface 137a is the upper half close to the vertex 111gp in the direction of gravity, and the second inclined surface 137b is the lower half on the opposite side of the vertex 111gp in the direction of gravity.

[0106] The first inclined surface 137a of one of the recovery grooves 137 is inclined from the upper side in the gravity direction toward the opening portion 120ah on the outer peripheral surface 111g of the tube portion 111 of the housing 110, and connects the opening portion 120ah to the outer peripheral surface 111g of the tube portion 111 of the housing 110. The second inclined surface 137b of one of the recovery grooves 137 is provided on the side opposite to the first inclined surface 137a in the circumferential direction of the outer peripheral surface 111g of the tube portion 111.

[0107] The first inclined surface 137a that defines one of the recovery grooves 137 is inclined downward from the position of the upper vertex 111gp toward one of the openings 120ah. This is to make it easier for the lubricating fluid that falls from the vicinity of the vertex 111gp of the outer peripheral surface 111g of the tube 111 to be recovered by the first inclined surface 137a and guided to one of the openings 120h.

[0108] In addition, the second inclined surface 137b that divides one of the recovery grooves 137 is inclined downward from one of the ribs 118a toward the opening 120ah of one of the inflow paths 120a. This is to make it easier for the lubricating fluid that falls along the rib 118 to be received by the second inclined surface 137b and flow into the opening 120ah of one of the inflow paths 120a.

[0109] like Figure 4 As shown in (B), another recovery tank 138 (arranged in the second quadrant) has a disk surface 138ab formed by a smooth surface in a circular shape in top view. The disk surface 138ab includes a first inclined surface 138a and a second inclined surface 138b, wherein the first inclined surface 138a is the upper half close to the vertex 111gp in the gravity direction, and the second inclined surface 138b is the lower half on the side opposite to the vertex 111gp in the gravity direction.

[0110] The first inclined surface 138a that defines the other recovery groove 138 (arranged in the second quadrant) is similar to the first inclined surface 137a, and is inclined downward from the position of the upper vertex 111gp toward the other opening 120bh. This is to facilitate the recovery of the lubricating fluid that falls from the vicinity of the vertex 111gp of the outer peripheral surface 111g of the tube 111 and guide it to the other opening 120bh.

[0111] The second inclined surface 138b defining the other recovery groove 138 is inclined downward from the other rib 118b toward the opening 120bh of the other inflow path 120b. This is to facilitate the lubricating fluid falling along the other rib 118b to be received by the second inclined surface 138b and guided to the opening 120bh of the other inflow path 120b.

[0112] The first inclined surface 137 a that defines one of the recovery grooves 137 (disposed in the first quadrant) and the first inclined surface 138 a that defines the other of the recovery grooves 138 (disposed in the second quadrant) are connected to each other via the connecting groove 130 .

[0113] The connecting groove 130 is a groove space that spatially connects one of the recovery grooves 137 and the other recovery groove 138 and allows the lubricating fluid to move freely between the one of the recovery grooves 137 and the other recovery groove 138 .

[0114] One of the ribs 118a is erected at the peripheral end of the second inclined surface 137b that defines one of the recovery grooves 137. In contrast, another of the ribs 118b is erected at the peripheral end of the second inclined surface 138b that defines the other of the recovery grooves 138.

[0115] However, the present invention is not limited thereto, and one rib 118a and the other rib 118b may be both erected near the peripheral end of the first inclined surface 137a and near the peripheral end of the second inclined surface 138a. In addition, near means that the lubricating fluid that hits one rib 118a and the other rib 118b can be recovered by the recovery groove 137 and the recovery groove 138.

[0116] When the lubricating fluid enters the communication groove 130 , it is guided to one of the inflow paths 120 a or the other of the inflow paths 120 b via the first inclined surface 137 a of one of the recovery grooves 137 or the first inclined surface 138 b of the other of the recovery grooves 138 .

[0117] In the sealing device 300 of the second embodiment, the lubricating fluid that hits one of the ribs 118a (arranged in the first quadrant) falls from the surface of the rib 118a and is received by the second inclined surface 137b of one of the recovery grooves 137, and then flows into the opening portion 120ah of one of the inflow paths 120a through the second inclined surface 137b.

[0118] Furthermore, in the sealing device 300, the lubricating fluid that hits the other rib 118b falls from the surface of the rib 118b and is received by the second inclined surface 138b of the other recovery groove 138, and then flows into the opening 120bh of the other inflow path 120b through the second inclined surface 138b.

[0119] Furthermore, in the sealing device 300, the lubricating fluid dispersed in the area between the two recovery grooves 137 and 138 will surely flow into the opening 120ah of one inflow path 120a or the opening 120bh of the other inflow path 120b via the first inclined surface 137a of one recovery groove 137 or the first inclined surface 138a of the other recovery groove 138 due to the presence of the connecting groove 130. Therefore, the lubricating fluid can be reliably supplied to the sliding portion 315 from one inflow path 120a or the other inflow path 120b.

[0120] Thus, the sealing device 300 allows the lubricating fluid collected by the gear (not shown) of the speed reducer 200 to flow in reliably from the opening 120ah of one inflow path 120a or the opening 120bh of the other inflow path 120b through the two recovery grooves 137 and 138. Therefore, in the sealing device 300, the sliding portion 315 of the mechanical seal 310 can be directly and effectively cooled and lubricated, and the lubricating fluid can lubricate the inside of the housing 210 of the speed reducer 200.

[0121] <Third embodiment>

[0122] Figure 5 It is a partially enlarged cross-sectional view showing the structure of a pipe portion of a casing according to a third embodiment of the present invention. Figure 6 FIG. 2 is a partially enlarged perspective view showing the structure of the tube portion of the housing according to the third embodiment of the present invention. Figure 5 and Figure 6 In the present invention, the same reference numerals are given to portions corresponding to the configurations of the first and second embodiments, and description thereof will be omitted.

[0123] like Figure 5 and Figure 6 As shown, in the sealing device 300 of the third embodiment, one inflow path 120a is formed at the position of the highest vertex 111gp on the upper side (arrow e direction) of the outer peripheral surface 111g in the gravity direction, and the other inflow path 120b is formed at a position deviated from the one inflow path 120a by about 45 degrees in the counterclockwise direction in the figure. Both the one inflow path 120a and the other inflow path 120b extend linearly from the recovery groove 140 described later toward the rotation axis X and penetrate the inner peripheral surface 111na of the tube portion 111.

[0124] In addition, the other inflow path 120b may be provided at any position deviated by 15 degrees or 30 degrees counterclockwise in the figure from the position of the vertex 111gp of the outer peripheral surface 111g of the tube portion 111, depending on the scattering direction of the lubricating fluid.

[0125] Thus, in the third embodiment, one inflow path 120a and the other inflow path 120b are provided at two locations on the outer peripheral surface 111g of the tube portion 111. However, the inflow paths 120a and 120b are not limited to two, and three or more inflow paths 120a and 120b may be provided between one rib 118a and the other rib 118b.

[0126] Here, a recovery groove 140 is formed in the pipe portion 111. The recovery groove 140 has a recovery portion 149 in which a concave space is formed by a bottom portion 149i described later and axially extending portions 149k and 149j described later.

[0127] The recovery portion 149 of the recovery groove 140 has an inclined portion 148a formed between a position where a vertex 111gp in the gravity direction of one of the inflow paths 120a is formed and one of the ribs 118a, and inclined from one of the ribs 118a toward an opening 120ah of one of the inflow paths 120a.

[0128] The inclined portion 148a is inclined downward from one of the ribs 118a on the upper side of the outer peripheral surface 111g of the tube portion 111 of the housing 110 in the gravity direction toward a bottom 149i of a recovery portion 149 described later and an opening 120ah of one of the inflow paths 120a.

[0129] Furthermore, the recovery portion 149 has an inclined portion 148 b that inclines from the other rib 118 b toward the bottom 149 i of the recovery portion 149 and the opening 120 bh of the other inflow path 120 b from top to bottom.

[0130] The bottom 149i of the recovery portion 149 is formed at the opening 120a of the one inflow path 120a and the opening 120bh of the other inflow path 120b. The function of the bottom 149i of the recovery portion 149 is the same as that of the communication groove 130 described above.

[0131] like Figure 6 As shown, the recovery portion 149 has two axially extending portions 149k and 149j extending in the axial direction. The axially extending portion 149k is inclined from the outer peripheral surface 111g of the tube portion 111 in the axial direction toward the opening 120ah of one inflow path 120a and the opening 120bh of the other inflow path 120b.

[0132] The axially extending portion 149k is an inclined surface that connects the openings 120ah and 120bh of the two inflow paths 120a and 120b from the outer circumferential surface 111g of the axially extending tube portion 111, and is an arc-shaped smooth curved surface that extends in the circumferential direction and connects one opening 120ah to the other opening 120bh. The axially extending portion 149k plays the role of recovering the lubricating fluid from the outer circumferential surface 111g of the tube portion 111 and causing it to flow into the opening 120ah of one inflow path 120a or the opening 120bh of the other inflow path 120b.

[0133] The axially extending portion 149j is inclined along the axial direction from the boundary portion between the outer peripheral surface 111g of the tube portion 111 and the flange portion 116 toward the opening 120ah of one inflow path 120a and the opening 120bh of the other inflow path 120b.

[0134] The axial extension portion 149j is an inclined surface that connects to the openings 120ah and 120bh of the two inflow paths 120a and 120b from the boundary portion between the outer peripheral surface 111g of the tube portion 111 and the flange portion 116 in the axial direction, and is an arc-shaped smooth curved surface that extends in the circumferential direction to connect one opening 120ah to the other opening 120bh. The axial extension portion 149j plays the role of recovering the lubricating fluid from the flange portion 116 and flowing it into the opening 120ah of one inflow path 120a or the opening 120bh of the other inflow path 120b.

[0135] The axially extending portion 149k and the axially extending portion 149j are both connected to the bottom portion 149i. The bottom portion 149i is a boundary line portion that connects the axially extending portion 149k and the axially extending portion 149j in the axial direction and connects one opening portion 120ah and the other opening portion 120bh in the circumferential direction.

[0136] As described above, the recovery portion 149 includes a bottom portion 149i and axially extending portions 149k and 149j extending axially, and is a concave space having a roughly "V"-shaped or roughly "U"-shaped cross-section divided by the axially extending portions 149k and 149j and the bottom portion 149i.

[0137] Here, the cross section of the recovery portion 149 is roughly "V"-shaped, which means, for example, that the cross section is roughly "レ" (Japanese katakana "レ")-shaped, and the bottom is not between the axial extension portion 149k and the axial extension portion 149j, but is close to a certain shape. In addition, the cross section of the recovery portion 149 is roughly "U"-shaped, which means, for example, that the cross section is roughly "し" (Japanese hiragana "し")-shaped, and the bottom is not between the axial extension portion 149k and the axial extension portion 149j, but is close to a certain shape.

[0138] In addition, the concave space with a substantially "V"-shaped or substantially "U"-shaped cross section that divides the recovery portion 149 is formed only by the axial extension portions 149k, 149j, and the bottom portion 149i, but is not limited thereto. For example, the axial extension portion 149k may also be formed by a flat surface extending vertically from the outer peripheral surface 111g of the tube portion 111 to the lower side in the gravity direction, and an inclined surface inclined from the lower end of the flat surface to the openings 120ah, 120bh of the two inflow paths 120a, 120b.

[0139] Similarly, the axial extension portion 149j can also be formed by two surfaces: a flat surface extending vertically toward the lower side in the direction of gravity from the junction of the outer peripheral surface 111g of the axial upper tube portion 111 and the flange portion 116, and an inclined surface inclined from the flat surface toward the opening portions 120ah, 120bh of the two inflow paths 120a, 120b.

[0140] At this time, the recovery portion 149 is formed into a concave space with a cross section that is roughly inverted pentagonal by the axial extension portion 149k and the axial extension portion 149j. In short, as long as the concave space forming the recovery portion 149 includes the bottom 149i and the two axial extension portions 149k and 149j connecting the bottom 149i in the axial direction, it can be said that it has a concave space with a cross section that is roughly "V"-shaped or a cross section that is roughly "U"-shaped.

[0141] The recovery portion 149 is a concave space with a roughly "V"-shaped or roughly "U"-shaped cross-section divided by the axial extension portion 149k, the axial extension portion 149j, and the bottom 149i, and an opening portion 120ah of one of the inflow paths 120a and an opening portion 120bh of the other inflow path 120b are provided on a straight line of the bottom 149i.

[0142] Specifically, the opening 120ah of one inflow path 120a is formed at the intersection of the bottom 149i of the partition recovery part 149 and the inclined part 148a. In addition, the opening 120bh of the other inflow path 120b is formed at the intersection of the bottom 149i of the partition recovery part 149 and the inclined part 148b.

[0143] Therefore, the circumferential range of the recovery portion 149 is a region between the inclined portions 148a and 148b in the circumferential direction and divided by the axially extending portion 149k and the axially extending portion 149j.

[0144] In addition, in the recovery tank 140, another inflow path 120b is arranged at a 45-degree lower side relative to one of the inflow paths 120a, and overall, it is inclined from the opening 120ah of one of the inflow paths 120a at the vertex 111gp position on the upper side of the gravity direction toward the opening 120bh of the other inflow path 120b on the lower side of the gravity direction.

[0145] Therefore, the lubricating fluid scattered or gathered along with the rotation of the gear 233 of the speed reducer 200 hits one of the ribs 118a or the other rib 118b and then falls from the surface of the one of the ribs 118a or the other rib 118b.

[0146] The recovery groove 140 efficiently receives the lubricating fluid dropped from the surface of one rib 118 a or the other rib 118 b using one inclined portion 148 a or the other inclined portion 148 b and stores the lubricating fluid in the recovery portion 149 .

[0147] In the recovery groove 140, the depth of the concave space of the recovery portion 149 is set in consideration of the balance between the flow rate of the lubricating fluid from the two inflow paths 120a, 120b and the storage amount of the lubricating fluid. Therefore, the recovery portion 149 of the recovery groove 140 does not store the lubricating fluid excessively, and avoids the situation where no lubricating fluid is stored in advance, and always stores an appropriate amount of lubricating fluid, and the lubricating fluid is always supplied to the sliding portion 315 of the mechanical seal 310 through the two inflow paths 120a, 120b.

[0148] In the sealing device 300 of the third embodiment, when the lubricating fluid is stirred and gathered by the gear 233 fixed to the reducer input shaft 201 of the reducer 200 , the lubricating fluid hits the two ribs 118 a and 118 b provided on the pipe portion 111 of the housing 110 .

[0149] Then, in the sealing device 300, the lubricating fluid falling along the surfaces of the two ribs 118a and 118b is received by one of the inclined portions 148a and the other inclined portion 148b, and is recovered and stored in the concave space through the axial extension portion 149k and the axial extension portion 149j of the recovery portion 149, while the lubricating fluid effectively flows into the opening portions 120ah and 120bh of the two inflow paths 120a and 120b.

[0150] In this way, the lubricating fluid temporarily stored in the recovery portion 149 of the recovery groove 140 flows into the speed reducer side space 124 from the openings 120ah and 120bh of the two inflow paths 120a and 120b, and cools and lubricates the sliding portion 315 of the mechanical seal 310 .

[0151] Then, the lubricating fluid drips downward (in the direction of arrow f) along the inner peripheral surface 111na of the tube portion 111 in the reducer side space 124, and is discharged to the inside of the housing 210 of the reducer 200 through the outflow path 122. In addition, after being discharged to the inside of the reducer 200, the lubricating fluid is stirred and gathered again by the gear 233, and is used again for cooling and lubricating the mechanical seal 310.

[0152] According to the above configuration, the sealing device 300 is provided with two inflow paths 120 a and 120 b , the recovery groove 140 , and the outflow path 122 at positions facing the mechanical seal 310 on the outer peripheral surface 111 g of the tube portion 111 of the housing 110 .

[0153] Thus, the sealing device 300 allows the lubricating fluid collected by the gear 233 of the reducer 200 to flow in from the two inflow paths 120a, 120b and be directly supplied to the sliding part 315 of the mechanical seal 310, thereby effectively cooling and lubricating the sliding part 315 of the mechanical seal 310, and the lubricating fluid can lubricate the interior of the housing 210 of the reducer 200.

[0154] In this way, the sealing device 300 can circulate the lubricating fluid of the reducer 200 through the two inflow paths 120a and 120b and the outflow path 122 of the tube portion 111, thereby improving the cooling and lubricating effects on the sliding portion 315 of the mechanical seal 310 using a small amount of lubricating fluid.

[0155] In addition, the sealing device 300 supplies the lubricating fluid to the reducer side space 124 via the two inflow paths 120a and 120b, and discharges the lubricating fluid from the reducer side space 124 via the outflow path 122, thereby realizing continuous circulation. Therefore, the lubricating fluid will not be retained in the reducer side space 124, and a high-cleanliness lubrication environment without residual foreign matter in the reducer side space 124 can be provided.

[0156] <Other embodiments>

[0157] In addition, the following situation is described in the first to third embodiments: the inner circumferential spline portion formed on the inner circumferential surface of the cylindrical portion 103 of the motor drive shaft 101 engages with the outer circumferential spline portion formed on the outer circumferential surface of the small diameter cylindrical portion 203 of the reducer input shaft 201, and the rotation (driving force) of the motor drive shaft 101 is transmitted to the reducer 200 via the reducer input shaft 201.

[0158] However, the present invention is not limited to this. The motor drive shaft 101 can also be formed into a cylindrical shape, and the front end portion of the reducer input shaft 201 is formed into a cylindrical shape. The outer peripheral spline portion formed on the outer peripheral surface of the cylindrical portion is engaged with the inner peripheral spline portion formed on the inner peripheral surface of the cylindrical portion, and the rotation (driving force) of the motor drive shaft 101 is transmitted to the reducer 200 via the reducer input shaft 201.

[0159] In the sealing device 300 of the first to third embodiments, the sliding portion 315 of the mechanical seal 310 is disposed in the space of the housing 210 of the speed reducer 200 and covered by the pipe portion 111 when viewed from above in the gravity direction (direction of arrow e).

[0160] However, the present invention is not limited to this, and the sliding portion 315 of the mechanical seal 310 may be covered by the housing 110 instead of the tube portion 111, and is arranged in the space of the housing 110 of the drive motor 100 when viewed from the upper side in the vertical direction (direction of arrow e).

[0161] At this time, in the sealing device 300 , the inflow paths 120 , 120 a , 120 b formed in the tube portion 111 of the housing 110 may be provided in a state of being inclined toward the sliding portion 315 of the mechanical seal 310 disposed on the driving motor side.

[0162] Furthermore, in the first and second embodiments, the case where the funnel-shaped recovery tank 127 is provided with respect to the inflow channel 120 is described. However, the present invention is not limited to this. Figure 7 As shown, a tapered inflow path 180 may be provided in which the entire flow path of the inflow path 120 gradually decreases in diameter from the upper side (in the direction of arrow e) to the lower side (in the direction of arrow f).

[0163] At this time, the lubricating fluid hitting the rib 118 of the flange portion 116 is easily received by the opening surface 180t of the inflow path 180, so that the lubricating fluid can flow in more efficiently. Therefore, instead of the linear outflow path 122, an inverted tapered outflow path 182 may be provided.

[0164] The sealing device 300 according to the first to third embodiments is applied to the driving motor 100 of an electric vehicle, but the application of the sealing device 300 according to the first to third embodiments is not limited thereto. The present invention can be applied to any configuration that can utilize the effects of the present invention.

[0165] The first to third embodiments and other embodiments of the present invention are described above, but the present invention is not limited to the first to third embodiments and other embodiments, but includes all forms contained in the concept of the present invention and the claims. In addition, each structure can be appropriately combined to achieve at least part of the above-mentioned subjects and effects. For example, the shape, material, configuration, etc. of each component can be appropriately changed according to the specific use form of the present invention.

[0166] Description of Reference Numerals

[0167] 100 driving motor; 101, 501 motor driving shaft; 102 cylindrical portion; 103 cylindrical portion; 110 housing; 111 pipe portion; 113 motor side bearing; 114 motor side space; 1116 flange portion; 118 rib; 20, 180 inflow path; 122, 182 outflow path; 123 reducer side bearing; 124 reducer side space; 127, 137, 138, 140 recovery tank; 127a , 137a the first inclined surface; 127b, 137b the second inclined surface; 148a, 148b inclined parts; 149 recovery part; 149i bottom; 200 reducer; 201 reducer input shaft; 202 large diameter cylindrical part; 203 small diameter cylindrical part; 210 housing; 300, 300a, 300b sealing device; 310 mechanical seal; 311 stationary ring; 312 rotating ring; 315 sliding surface.

Claims

1. A sealing device, characterized in that: include: case; as well as A mechanical seal seals a lubricating fluid by means of a sliding portion, wherein the sliding portion is formed by a rotating ring fixed to the outer peripheral surface of a rotating shaft and a stationary ring fixed to the inner peripheral surface of the housing facing and contacting each other in the axial direction. The housing comprises: a recovery groove formed on the outer peripheral surface of the housing and used to recover the lubricating fluid scattered from the outside of the housing; as well as at least one inflow path, which penetrates from the recovery groove to the inner peripheral surface of the housing and has an opening portion connected to the recovery groove upward in the gravity direction, so that the lubricating fluid recovered by the recovery groove flows into the sliding portion of the mechanical seal, The recovery trough has an inclined surface inclined from the upper side in the gravity direction toward the opening. A rib protruding from the outer peripheral surface of the shell is formed on the outer peripheral surface of the shell, The rib is erected at an end of the recovery trough or at a position close to the end so as to sandwich a surface of the inclined surface of the recovery trough on the opposite side to the vertex in the gravity direction between the opening and the rib.

2. The sealing device according to claim 1, wherein: The recovery tank is substantially in the shape of a frustum.

3. The sealing device according to claim 2, wherein: The recovery groove, the opening, and the inflow path are formed on the outer peripheral surface of the housing at positions within 45 degrees on both sides in the circumferential direction from the vertex position in the gravity direction.

4. The sealing device according to claim 3, wherein: The housing includes a plurality of the inflow paths and the recovery grooves formed with the openings. The housing has a communication groove that connects the plurality of recovery grooves to each other.

5. A sealing device, characterized in that: include: case; and A mechanical seal seals a lubricating fluid by means of a sliding portion, wherein the sliding portion is formed by a rotating ring fixed to the outer peripheral surface of a rotating shaft and a stationary ring fixed to the inner peripheral surface of the housing facing and contacting each other in the axial direction. The housing comprises: a recovery groove formed on the outer peripheral surface of the housing and used to recover the lubricating fluid scattered from the outside of the housing; and a plurality of inflow paths, which penetrate from the recovery groove to the inner peripheral surface of the housing and have an opening portion connected to the recovery groove upward in the gravity direction, so that the lubricating fluid recovered by the recovery groove flows into the sliding portion of the mechanical seal, The recovery groove comprises: a recovery portion, whose radial cross section is approximately "V"-shaped or substantially "U"-shaped; and an inclined portion, which is connected to the recovery portion in the circumferential direction and extends in the circumferential direction, and is inclined from the upper side to the bottom of the recovery portion in the direction of gravity, and the opening portion is arranged at the bottom of the recovery portion, A rib protruding from the outer peripheral surface of the shell is formed on the outer peripheral surface of the shell, The rib is provided upright at an end portion of the recovery trough or at a position close to the end portion so as to sandwich the inclined portion of the recovery trough between the opening portion and the rib.

6. The sealing device according to claim 5, wherein: The opening is provided at an intersection where the bottom of the recovery portion and the inclined portion intersect.

7. The sealing device according to claim 1 or 5, wherein: The sealing device is used to seal the lubricating fluid of the reducer.

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