JP2006183763A - Rolling bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device with improved reliability by preventing leakage of grease while securing lubrication performance. <P>SOLUTION: In the rolling bearing device used in a compressor device for a fuel cell, and provided with a pair of rolling bearings 4 bearing a rotary shaft 3 fixed with a component such as a compressor, the rolling bearing 4 is provided with an outer ring 12 formed with an outer side rolling face 12a on an inner circumference, an inner ring 13 formed with an inner side rolling face 13a on an outer circumference, and a plurality of balls 15 housed so as to freely roll between the rolling faces via a retainer 14. An annular grease storing part 21 connected to the outer side rolling face 12a is formed on an inner circumferential face of the outer ring 12, and grease 22 is filled in an annular space between the inner circumferential face of the outer ring 12 and an outer diameter of the retainer 14. By this, leakage of the lubricating grease can be prevented while securing lubrication performance, and mixing of leaked grease into gas and fouling of a cathode and an anode can be prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rolling bearing device that supports a rotating shaft to which components such as an impeller compressor are fixed, and more particularly to a rolling bearing device used in a compressor device for a fuel cell.

  A fuel cell is a power generation device that takes out electric energy by chemically reacting hydrogen and oxygen supplied from the outside, and is a solid that is generally applied to, for example, a fuel cell for an automobile by an electrolyte used in the fuel cell. It is classified into a polymer type, a phosphate electrolyte type, a molten carbonate type, and a solid oxide type. Regardless of the type of fuel cell, both sides of the electrolyte or electrolyte membrane are sandwiched between both cathode (oxygen electrode) and anode (fuel electrode) electrodes, and oxygen in the air is supplied as the oxidant gas to the cathode side. At the same time, a unit cell in which hydrogen is supplied as fuel gas to the anode side is formed as a single cell, and each cell through separators is stacked to form a stack.

  There are a turbocharger system in which the compressor is driven by an exhaust gas turbine and a motor drive system in which the compressor is driven by a motor in order to supply air by pumping to the cathode side of such a fuel cell. Further, when supplying oxygen and hydrogen to the fuel cell, for example, in the case of a solid polymer type or the like, it is necessary to react by adding water vapor even in a direct hydrogen type that uses hydrogen directly as a fuel. Furthermore, for example, in a reformed fuel type using gasoline or the like as the fuel, very high temperature steam is required. Since water vapor is required in this way, a compressor that pumps water vapor is generally used for the purpose of increasing energy efficiency.

  In this compressor, a rolling bearing is used to rotatably support an impeller attached to a rotating shaft, and a predetermined amount of grease for lubrication is filled in the bearing. However, since grease usually generates more dust when softened, dust generated from grease easily adheres to the fuel cell stack during operation, and in some cases, this deposit acts as a catalyst poison for the fuel cell stack. It is possible. Therefore, a grease having an initial mixing degree of 250 to 295 at 25 ° C. is generally used in consideration of lubricity. The grease having such a blending degree has a large degree of softening, and it cannot be said that the reliability of the fuel cell stack is sufficient.

  As a solution to this problem, a rolling bearing device shown in FIG. 5 is known. The rolling bearing device 50 includes a housing 51, a rotating shaft 52 fitted in the housing 51, and a pair of rolling bearings 53 and 53 that rotatably support the rotating shaft 52 with respect to the housing 51. .

  One end portion of the rotating shaft 52 protrudes from one rolling bearing 53, and an impeller 54 is attached to the tip side thereof. A seal portion is provided between the back surface of the impeller 54 and the rolling bearing 53. The seal portion is disposed between a bush 55 externally attached to the rotary shaft 52, a sealing member 56 mounted in a groove formed on the outer peripheral surface of the bush 55, and the back plate 57 and the rolling bearing 53. Baffle 58. Here, the sealing member 56 seals a gap between the outer peripheral surface of the bush 55 and the inner peripheral surface of the back plate 57. Further, the end of the bush 55 is in contact with the side surface of the inner ring 64 of the rolling bearing 53.

  In this rolling bearing device 50, the impeller 54 rotates as the rotary shaft 52 rotates at high speed, and the water vapor sucked from the water vapor suction port 59 is pressurized by the impeller 54, and is formed by the impeller housing 60 and the back plate 57. Then, the water is discharged from the water vapor outlet 62 through the pressure volute 61.

Here, in the rolling bearing 53 that rotatably supports the rotating shaft 52, as shown in FIG. 6, a ball 66 is rotatably held via a cage 65 between an outer ring 63 and an inner ring 64. Further, seals 67 are attached to both ends of the outer ring 63 to prevent the grease filled in the space 68 formed by the outer ring 63, the inner ring 64, and the ball 66 from leaking to the outside and to prevent water vapor from the outside. This prevents foreign matter such as the intrusion into the bearing. The grease has an initial mixing consistency of 150 to 240 at 25 ° C. Thereby, the degree of softening of the grease can be reduced and dust generation can be suppressed.
JP 2004-47474 A

  In such a conventional rolling bearing device 50, the grease filled in the rolling bearing 53 has an initial mixing consistency of 150 to 240 at 25 ° C., so that the degree of softening of the grease is reduced to suppress dust generation. And the reliability of the fuel cell stack can be improved. However, during long-term operation, there is a risk that water vapor or the like may enter the bearing due to deterioration or wear of the seal 67 due to organic gas. In this case, even if the initial penetration is set to 150 to 240, the grease sealed inside the bearing, in particular, the grease staying in the vicinity of the seal lip may be softened and leak to the outside of the bearing. When the leaked grease is mixed into the gas and sent into the apparatus, the exposed cathode and anode (not shown) are contaminated, and the power generation efficiency of the cell is deteriorated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rolling bearing device that prevents lubrication of grease and improves reliability while ensuring lubrication performance.

  In order to achieve the object, the invention according to claim 1 of the present invention is a rolling bearing device used in a compressor device of a fuel cell, and is a cylindrical housing, and is fitted into the housing, and the compressor device is A rolling bearing device comprising: a rotating shaft to which the components are fixed; and a sealed rolling bearing that is interposed between the rotating shaft and the housing and rotatably supports the rotating shaft with respect to the housing The rolling bearing includes an outer ring having an outer race surface formed on the inner periphery, an inner ring having an inner race surface facing the outer race surface on the outer periphery, and a cage between the two race surfaces. A plurality of rolling elements accommodated so as to be freely rollable via the outer ring, and contact-type seals that are attached to both ends of the outer ring and slidably contact the inner ring, and the outer raceway surface on the inner peripheral surface of the outer ring Annular grease storage leading to There was adopted a structure that is formed.

  As described above, the cylindrical housing, the rotary shaft inserted in the housing and having the compressor component fixed thereto, and the rotary shaft interposed between the rotary shaft and the housing are rotatable with respect to the housing. In a rolling bearing device having a sealed-type rolling bearing supported on a rolling bearing, an outer ring having an outer rolling surface formed on the inner periphery and an inner rolling surface facing the outer rolling surface formed on the outer periphery are formed. An inner ring, a plurality of rolling elements accommodated between both rolling surfaces via a cage, and contact type seals that are attached to both ends of the outer ring and are in sliding contact with the inner ring. Since the annular grease storage portion connected to the outer rolling surface is formed on the inner peripheral surface of the outer peripheral surface, it is difficult for the grease to be discharged from the outer rolling surface of the outer ring, and leakage of the grease to the outside can be prevented. Therefore, the leaked grease is not mixed in the gas and does not contaminate the exposed cathode and anode, and a rolling bearing device with improved reliability can be provided. The grease storage part may be a groove.

  Preferably, as in the invention according to claim 2, if grease is filled aiming at an annular space between the inner peripheral surface of the outer ring and the outer diameter of the cage, the grease stays in the vicinity of the seal lip of the seal. The amount of grease adhering to the seal along with the rotation of the grease and the inner ring can be suppressed, and leakage of the grease to the outside can be further prevented.

  Further, as in the invention according to claim 3, the rolling bearing is composed of a pair of deep groove ball bearings, and the grease storage portions may be formed on both sides of the outer rolling surface of the outer ring. As in the invention described in claim 4, the rolling bearing comprises a pair of angular ball bearings or double row angular ball bearings provided with a predetermined contact angle, and the rolling bearing is disposed on one side of the outer rolling surface of the outer ring. A grease reservoir may be formed.

  Further, as in the invention according to claim 5, if the seal is made of a synthetic rubber excellent in heat resistance and chemical resistance and is a contact type that is in sliding contact with the inner ring, in a long-term operation, It is possible to prevent deterioration and wear of the seal due to organic gas, and to prevent water vapor and the like from entering the bearing.

  A rolling bearing device according to the present invention is a rolling bearing device used in a compressor device for a fuel cell, and includes a cylindrical housing, a rotary shaft that is fitted in the housing, and to which the components of the compressor device are fixed, In a rolling bearing device including a sealed-type rolling bearing that is interposed between the rotating shaft and the housing and rotatably supports the rotating shaft with respect to the housing, the rolling bearing is disposed on an inner periphery. An outer ring formed with an outer rolling surface, an inner ring formed with an inner rolling surface opposed to the outer rolling surface on the outer periphery, and accommodated between the both rolling surfaces via a cage. A plurality of rolling elements and contact-type seals that are attached to both end portions of the outer ring and slidably contact the inner ring, and an annular grease storage portion that is connected to the outer rolling surface is formed on the inner peripheral surface of the outer ring. Jun Oils such as grease hardly is discharged from the outer raceway surfaces of the outer ring, it is possible to prevent leakage of the grease outside. Therefore, the leaked grease is not mixed in the gas and does not contaminate the exposed cathode and anode, and a rolling bearing device with improved reliability can be provided.

  A rolling bearing device used in a compressor device of a fuel cell, which is a cylindrical housing, a rotary shaft that is fitted in the housing and to which the components of the compressor device are fixed, and between the rotary shaft and the housing A rolling bearing device provided with a sealed type rolling bearing that is interposed in the housing and rotatably supports the rotating shaft with respect to the housing, wherein the rolling bearing has an outer ring formed with an outer rolling surface on the inner periphery. And an inner ring having an inner rolling surface facing the outer rolling surface on the outer periphery, a plurality of balls accommodated between the rolling surfaces via a cage, and both ends of the outer ring. A contact-type seal that is slidably in contact with the inner ring, and an annular grease storage portion that is connected to the outer rolling surface is formed on the inner peripheral surface of the outer ring, and the inner peripheral surface of the outer ring Outer diameter of the cage Eyeing an annular space is grease is filled in.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a rolling bearing device according to the present invention, and FIG. 2 is an enlarged view of a main part showing a bearing portion of FIG. In addition, the same code | symbol is attached | subjected to the same component and the same site | part, and the overlapping description is abbreviate | omitted.

  The rolling bearing device 1 includes a housing 2, a rotating shaft 3 fitted in the housing 2, and a pair of rolling bearings 4 and 4 that rotatably support the rotating shaft 3 with respect to the housing 2. .

  One end of the rotating shaft 3 protrudes from one rolling bearing 4, and an impeller 6 is attached to the tip end side via a fixing nut 5. A small-diameter portion 7 is formed on the inner periphery of the housing 2, and is opposed to the shoulder portion 3 a of the rotating shaft 3 through a slight radial clearance to form a so-called labyrinth seal 8. The labyrinth seal 8 closes the back surface 6 a of the impeller 6 and the rolling bearing 4. A lid member 19 is attached to the housing 2. A shaft seal 19a slidably contacting the rotary shaft 3 is attached to the inner periphery of the lid member 19, and the opening of the housing 2 is closed.

  In the rolling bearing device 1, the impeller 6 rotates as the rotating shaft 3 rotates at high speed, and the water vapor sucked from the water vapor suction port 9 is pressurized by the impeller 6, and is formed by the impeller housing 10 and the housing 2. It is pumped through the pressure volute 11.

  Here, the pair of rolling bearings 4 and 4 are deep groove ball bearings, and as shown in an enlarged view in FIG. 2, an outer ring 12 having an outer rolling surface 12a formed on the inner periphery and an inner rolling surface 13a on the outer periphery. An inner ring 13 formed with a rolling element, a rolling element (ball) 15 accommodated between the rolling surfaces 12a and 13a via a cage 14, and an inner ring contact type mounted on both ends of the outer ring 12. The seals 16 and 16 are provided. The seals 16 and 16 prevent the lubricating grease sealed inside the bearing from leaking to the outside and prevent foreign matters such as water vapor from entering the bearing from the outside.

  Spacers 17 and 18 are mounted between the outer rings 12 and 12 and between the inner rings 13 and 13, and the pair of rolling bearings 4 and 4 are positioned. That is, the outer rings 12 and 12 are positioned and fixed in the axial direction while being sandwiched between the spacer 17 and the housing 2 and the lid member 19, and the inner rings 13 and 13 are connected to the spacer 18 and the shoulder 3 a of the rotary shaft 3. And it is positioned and fixed while being clamped by the fixing nut 20. The pair of rolling bearings 4 and 4 may be angular ball bearings, and preload may be applied to the rolling bearings 4 and 4 by the spacers 17 and 18. Thereby, the touch of the rotating shaft 3 can be suppressed and the rigidity of the rolling bearing device 1 can be improved.

  3A and 3B show the rolling bearing 4 according to the present embodiment, in which FIG. 3A is a longitudinal sectional view, and FIG. 3B is a side view of the state in which the seal 16 of FIG. In the rolling bearing 4, an annular grease storage portion 21 connected to the outer rolling surface 12 a is formed on the inner peripheral surface of the outer ring 12. Further, the grease 22 is filled in aiming at the annular space between the inner peripheral surface of the outer ring 12 and the outer diameter of the cage 14. As a result, the grease 22 is stored in the grease storage portion 21 via the outer rolling surface 12 a of the outer ring 12. Since the grease reservoir 21 is connected to the outer rolling surface 12a, the base oil (lubricating oil) is supplied again to the outer rolling surface 12a from the grease 22 stored in the grease reservoir 21.

  As described above, the grease 22 filled between the outer ring 12 and the cage 14 is stored in the grease storage unit 21, and the grease 22 is repeatedly supplied to the outer raceway surface 12 a of the outer ring 12 as the circulation base. Therefore, it is difficult for the lubricating oil to be discharged from the outer raceway surface 12 a of the outer ring 12. Further, since the grease 22 is filled aiming at the annular space between the inner peripheral surface of the outer ring 12 and the outer diameter of the retainer 14, the grease stays in the vicinity of the seal lip of the seal 16 and seals as the inner ring 13 rotates. The amount of grease adhering to 16 can be suppressed, and leakage of grease to the outside can be prevented. Therefore, the leaked grease is not mixed in the gas and does not contaminate the exposed cathode and anode, and a rolling bearing device with improved reliability can be provided.

  Further, the seal 16 in the present embodiment is formed of polyacryl rubber, fluoro rubber, or ethylene / propylene rubber (EPDM) having excellent heat resistance and chemical resistance. Among them, ethylene / propylene rubber is a terpolymer of ethylene, propylene, and a diene monomer for crosslinking, and enables sulfur crosslinking (vulcanization) by copolymerizing a third component that is a non-conjugated diene monomer. It has low chemical and chemical resistance equivalent to polyacrylic rubber. This prevents deterioration and wear of the seal 16 due to organic gas during long-term operation, prevents water vapor from entering the bearing, and further prevents grease from leaking outside the bearing. can do.

  Here, although the rolling bearing 4 which consists of a pair of deep groove ball bearing was illustrated, it does not necessarily restrict to such a structure. For example, the rolling bearing 23 which consists of a double row angular contact ball bearing as shown in FIG. 4 may be sufficient. In addition, the same code | symbol is attached | subjected to the site | part, the same components, or site | part which has the same function as embodiment mentioned above, and the detailed description is abbreviate | omitted.

  The rolling bearing 23 includes an outer ring 24 having double-row outer rolling surfaces 24a and 24a formed on the inner periphery, and a double-row inner rolling surface facing the double-row outer rolling surfaces 24a and 24a on the outer periphery. The inner ring 25 having 25a and 25a formed thereon, the rolling elements 15 and 15 accommodated so as to roll between the rolling surfaces 24a and 25a via the cages 26 and 26, and both ends of the outer ring 24 are mounted. Contact-type seals 16 and 16. The cage 26 is a snap-on type, and is formed by injection molding a synthetic resin containing a reinforcing material such as GF (glass fiber) based on PA (polyamide) 66.

  Both rolling surfaces 24a and 25a are formed so that a contact angle with the rolling element 15 is 15 to 30 °, and the outer rolling surface 24a and the rolling element 15 are arranged on one side of the outer rolling surface 24a of the outer ring 24. An annular grease storage portion 27 connected to the outer rolling surface 24a is formed so as to ensure the contact surface (contact ellipse). Further, the grease 22 is filled with an aim of an annular space between the inner peripheral surface of the outer ring 24 and the outer diameter of the cage 26. As a result, the grease 22 is stored in the grease storage portion 27 via the outer rolling surface 24 a of the outer ring 24. Since the grease reservoir 27 is connected to the outer rolling surface 24a, the base oil is supplied from the grease 22 stored in the grease reservoir 27 to the outer rolling surface 24a and the inner rolling surface 25a.

  Also in the present embodiment, the grease 22 filled between the outer ring 24 and the cage 26 is stored in the grease storage portion 27, and the grease 22 is repeatedly supplied to the outer rolling surface 24a of the outer ring 24 as the circulation base. Therefore, the lubricating oil is difficult to be discharged from the outer raceway surface 24a of the outer ring 24, and the amount of grease remaining in the vicinity of the seal lip of the seal 16 can be suppressed, thereby preventing the grease from leaking to the outside. be able to.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The rolling bearing device according to the present invention is used in a compressor device for a fuel cell, and can be applied to a rolling bearing device that supports a rotating shaft to which components such as a compressor are fixed.

It is a longitudinal section showing one embodiment of a rolling bearing device concerning the present invention. It is a principal part enlarged view which shows the bearing part of FIG. (A) is a longitudinal cross-sectional view which shows embodiment of the rolling bearing which concerns on this invention. (B) is a side view of the state which removed the seal of (a). It is a longitudinal cross-sectional view which shows other embodiment of the rolling bearing which concerns on this invention. It is a longitudinal cross-sectional view which shows the conventional rolling bearing apparatus. It is a principal part enlarged view which shows the bearing part of FIG.

Explanation of symbols

1 ... Rolling bearing device 2 ... Housing 3a ...・ ・ ・ ・ ・ ・ ・ ・ Shoulder 3 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotating shaft 4, 23 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ Rolling bearings 5 and 20 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fixing nut 6 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Impeller 6a ... Back side 7 ... Small diameter part 8 ... ..... Labyrinth seal 9 ..... Water vapor inlet 10 ...・ ・ ・ ・ ・ ・ Impeller housing 11 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Pressure volute 12, 24 ・... outer rings 12a, 24a ... outer rolling surfaces 13, 25 ... .... Inner rings 13a, 25a ... Inside rolling surfaces 14, 26 ... Cage 15 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling element 16 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal 17, 18 ・ ・ ・ ・ ・ ・ ・ ・.. Spacer 19 ... Lid member 19a ... Shaft seal 21, 27 ... ... Grease reservoir 22 ... Grease 50 ...・ ・ ・ ・ ・ Rolling bearing device 51 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Housing 52・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotating shaft 53 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling bearing 54 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Impeller 55 ... Bush 56 ... Sealing member 57 ... back plate 58 ... baffle 59 ... · · · · · Water vapor inlet 60 · · · · · · · Impeller housing 61 · · · · · · .... Pressure volute 62 ... Water vapor outlet 63 ... Outer ring 64 ... .... Inner ring 65 ...・ ・ ・ ・ ・ ・ ・ ・ Cage 66 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Ball 67 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ Seal 68 ...

Claims (5)

A rolling bearing device used in a compressor device of a fuel cell,
A cylindrical housing;
A rotating shaft fitted into the housing and fixed with the components of the compressor device;
In a rolling bearing device including a sealed type rolling bearing interposed between the rotating shaft and the housing and rotatably supporting the rotating shaft with respect to the housing,
The rolling bearing includes an outer ring having an outer rolling surface formed on the inner periphery, an inner ring having an inner rolling surface opposed to the outer rolling surface on the outer periphery, and a cage between both rolling surfaces. A plurality of rolling elements housed so as to be freely rollable, and contact-type seals that are attached to both ends of the outer ring and slidably contact the inner ring, and are connected to the outer rolling surface on the inner peripheral surface of the outer ring. A rolling bearing device in which an annular grease storage portion is formed.   The rolling bearing device according to claim 1, wherein grease is filled with aiming at an annular space between an inner peripheral surface of the outer ring and an outer diameter of the cage.   The rolling bearing device according to claim 1, wherein the rolling bearing includes a pair of deep groove ball bearings, and the grease storage portions are formed on both sides of the outer rolling surface of the outer ring.   The rolling bearing comprises a pair of angular contact ball bearings or double row angular contact ball bearings each having a predetermined contact angle, and the grease storage portion is formed on one side of the outer raceway surface of the outer ring. 2. The rolling bearing device according to 2.   The rolling bearing device according to any one of claims 1 to 4, wherein the seal is made of a synthetic rubber having excellent heat resistance and chemical resistance and is a contact type that is in sliding contact with the inner ring.

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