JP5556324B2 - Sealing device and rolling bearing - Google Patents

Description

  The present invention relates to a rolling bearing with a sealing device, and more particularly to a rolling bearing with a sealing device suitable for rotatably supporting a roll neck portion of a roll used in a rolling mill or the like.

  General machine equipment includes a steady operation machine in which the rotation speed and load do not fluctuate and a variable operation machine in which the rotation speed and load change stepwise or continuously. Since the rotational speed and load of the steady operation machine do not vary, the temperature in the bearing is maintained at a substantially constant temperature. On the other hand, the temperature in the bearing of the variable operating machine varies depending on the operating conditions due to changes in the dynamic friction torque and the bearing clearance. For example, roll neck bearings such as rolling mills that change the load when rolling slabs and continuous casting machines that cast high-temperature slabs are hot during slab rolling and are cooled by cooling water after passing through the slab. The internal temperature changes. For this reason, the volume in the bearing expands and contracts in proportion to the temperature, and a pressure difference is generated inside and outside the bearing space. When the bearing space pressure rises, the lubricant may leak out from the contact portion of the seal lip of the seal member. When the bearing space pressure drops, water, iron powder, etc. There is a problem that the foreign matter enters the bearing space and greatly affects the bearing life.

  In order to cope with such a problem, conventionally, a roll bearing device for a hot processing facility has been disclosed in which pressure adjusting means is disposed in a housing or the like outside the bearing to control pressure fluctuations in the bearing. (For example, refer to Patent Document 1). In addition, a rolling bearing sealing device has been proposed in which a valve mechanism is provided in an elastic body portion of a seal member to adjust a pressure difference between the inside and outside of the bearing (see, for example, Patent Document 2).

JP-A-5-231422 JP 2004-52924 A

  However, in the roll bearing device for hot processing equipment described in Patent Document 1, it is necessary to modify the pressure adjusting means, the housing for attaching the pressure adjusting means, and related parts, which requires a great deal of cost. . Further, since the pressure adjusting means is disposed outside the bearing, there is a problem that the bearing device becomes large. Further, in the rolling bearing sealing device described in Patent Document 2, although the pressure difference between the inside and outside of the bearing can be adjusted, there is a problem that the structure of the seal member is complicated and the manufacturing cost is high, and there is room for improvement. there were.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to control pressure fluctuation in the bearing only by adding a simple mechanism to the bearing, improve the sealing performance of the bearing, and lubricate from the inside. An object of the present invention is to provide a rolling bearing with a sealing device that can prevent leakage of an agent and entry of foreign matter from the outside.

The above object of the present invention can be achieved by the following constitution.
(1) It has a metal core and an elastic seal body, and is fixed to one of the inner peripheral surface of the outer ring of the rolling bearing or the outer peripheral surface of the inner ring, and slides on the inner peripheral surface of the outer ring or the other outer peripheral surface of the inner ring A sealing device that contacts and seals the inside of the bearing,
The core bar includes a first core bar extending in the radial direction and a second core bar extending in the radial direction,
The first metal core is formed in a ring shape having a substantially L-shaped cross section, and is formed between a plurality of holes provided on a side surface and extending along a circumferential direction, and the adjacent holes. A column connecting the outer peripheral side and the inner peripheral side of
The elastic sealing body includes a connecting portion that connects the first core metal and the second core metal, and a lip that is fixed to the second core metal and that is in sliding contact with the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. A thin-walled elastic deformation portion that is formed so as to close the hole and elastically deforms according to the pressure inside the bearing to maintain the inside of the bearing at a constant pressure ,
The said lip | rip part is urged | biased by the diameter reduction direction with a coil spring, The sealing device characterized by the above-mentioned .
(2) The sealing device according to (1), wherein the circumferential length of the column portion is longer than the circumferential length of the hole.
( 3 ) An outer ring having an outer ring raceway groove on the inner peripheral surface, an inner ring having an inner ring raceway groove on the outer peripheral surface, and a plurality of rolling elements arranged to be freely rollable between the outer ring raceway groove and the inner ring raceway groove, A sealing device that is fixed to one of the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring and that seals the inside of the bearing by sliding contact with the other of the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. A rolling bearing,
A rolling bearing, wherein the sealing device is the sealing device according to (1) or (2) .

  According to the rolling bearing with a sealing device of the present invention, the elastic seal body of the sealing device includes the lip portion that is in sliding contact with the rolling wheel and the thin-walled elastic deformation portion that is elastically deformed according to a pressure change inside the bearing. The pressure inside the bearing can be maintained substantially constant. As a result, the sealability of the bearing can be improved, the leakage of the lubricant accompanying the pressure fluctuation in the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended.

It is principal part sectional drawing of 1st Embodiment of the rolling bearing with a sealing device which concerns on this invention. It is a principal part side view of the sealing device shown in FIG. It is principal part sectional drawing of 2nd Embodiment of the rolling bearing with a sealing device which concerns on this invention. It is principal part sectional drawing of 3rd Embodiment of the rolling bearing with a sealing device which concerns on this invention. It is principal part sectional drawing of 4th Embodiment of the rolling bearing with a sealing device which concerns on this invention. It is principal part sectional drawing of 5th Embodiment of the rolling bearing with a sealing device which concerns on this invention.

  Hereinafter, each embodiment of a rolling bearing with a sealing device according to the present invention will be described in detail based on the drawings. In the following description, a self-aligning roller bearing will be described as an example.

(First embodiment)
First, with reference to FIG.1 and FIG.2, 1st Embodiment of the rolling bearing with a sealing device which concerns on this invention is described.

  As shown in FIGS. 1 and 2, the rolling bearing 10A with a sealing device according to the present embodiment is a self-aligning roller bearing, and includes an outer ring 11 having a spherical outer ring raceway groove 11a formed on an inner peripheral surface, and an outer periphery. A spherical inner ring raceway groove 12a is formed in two rows on the surface, and is held rotatably by a cage 13, and is aligned in two rows between the outer ring raceway groove 11a and the inner ring raceway groove 12a. A barrel-shaped roller 14 that is a plurality of rolling elements that are freely rollable, and a sealing device 15 that is disposed at both axial ends between the outer ring 11 and the inner ring 12 and seals the inside of the bearing. .

  The sealing device 15 includes a cored bar 21 in which a metal plate is formed in a ring shape having a substantially L-shaped cross section, and an elastic seal body 22 formed of an elastic material such as rubber. The elastic seal body 22 includes: It is attached to the surface side of the cored bar 21. The elastic seal body 22 extends further in the inner diameter direction from the cored bar 21, and a seal lip 22a is provided on the inner diameter side.

  In the sealing device 15, the core metal 21 is press-fitted and fixed to the inner peripheral surface 11 b provided at both ends of the outer ring 11, and the seal lip 22 a urged in the diameter reducing direction by the coil spring 23 includes an inner ring. 12 is elastically slidably contacted with the outer peripheral surface 12b to seal between the outer ring 11 and the inner ring 12.

  In addition, as shown in FIG. 2, a plurality of long holes 24 whose longitudinal direction extends along the circumferential direction of the cored bar 21, and adjacent elongated holes 24 are formed on the side surface of the cored bar 21 having a substantially L-shaped cross section. A column portion 25 that is formed between the outer peripheral side and the inner peripheral side of the cored bar 21 is formed. Since the long hole 24 is easy to process, it is preferable to form both ends in a semicircular shape as shown in FIG. 2, but both ends may be formed in a straight line. The column portion 25 acts to prevent deformation of the sealing device 15 when a radial load is applied to the rolling bearing with a sealing device 10A (sealing device 15). For this reason, it is more preferable that the circumferential length of the column portion 25 is set longer than the circumferential length of the long hole 24.

  The long hole 24 is closed by an elastic seal body 22 attached to the core metal 21, and the elastic seal body 22 corresponding to the long hole 24 constitutes an elastic deformation portion 26. The elastic deformation portion 26 is formed to a thickness equivalent to the plate thickness of the elastic seal body 22 from a film thickness of about 0.01 mm, and can be easily elastically deformed according to the pressure inside the bearing.

  In the rolling bearing 10A with the sealing device configured as described above, when the temperature of the bearing 10A rises and the pressure inside the bearing increases, the elastic deformation portion 26 expands outward along with this, and this pressure rise is absorbed. To do. Further, when the temperature of the bearing 10A is lowered and the pressure inside the bearing is lowered, the elastic deformation portion 26 is recessed inward to absorb this pressure drop. In other words, the elastic deformation portion 26 expands in accordance with the pressure inside the bearing, or indents inward to absorb the pressure fluctuation, and maintains the pressure inside the bearing at a substantially constant pressure. As a result, the sealability of the bearing 10A is improved, and leakage of the lubricant and entry of foreign matter from the outside are prevented.

  As described above, according to the rolling bearing with a sealing device 10A of the present embodiment, the elastic seal body 22 of the sealing device 15 is slidably contacted with the outer peripheral surface 12b of the inner ring 12 and the pressure inside the bearing. Therefore, the pressure inside the bearing can be maintained substantially constant by the expansion and contraction of the elastic deformation portion 26. As a result, the sealability of the bearing 10A can be improved, the leakage of the lubricant accompanying the pressure fluctuation inside the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended.

  Further, according to the rolling bearing 10A with the sealing device of the present embodiment, the cored bar 21 includes the column portion 25 that connects the outer peripheral side and the inner peripheral side, so that even if a radial load acts on the sealing device 15. The deformation can be suppressed with the minimum deformation, and the elastic deformation portion 26 can act stably and maintain the pressure inside the bearing substantially constant.

  Further, according to the rolling bearing with a sealing device 10A of the present embodiment, the elastically deforming portion 26 that is a pressure adjusting mechanism can be disposed in a portion that does not affect the bearing dimensions and the bearing mounting structure. It can be easily installed on the customer's existing machinery without modifying the housing.

  10 A of rolling bearings with a sealing device comprised as mentioned above can be used conveniently for the continuous casting installation of a steel mill, etc., for example. In a continuous casting machine, about several hundred rolls are used, and each roll has at least two bearings. Therefore, the total number of bearings used in a continuous casting machine can reach several thousand. .

  Since the bearing of such a continuous casting facility is exposed to a high temperature when the slab passes over the roll, the inner volume of the bearing expands. On the other hand, when the slab is not passing, the roll is cooled by a large amount of roll cooling water, so that the bearing temperature is lowered and the volume in the bearing is contracted. The area around the bearing of the continuous casting facility is an environment in which a very large amount of foreign matter exists such as a scale falling off from the slab, a large amount of roll cooling water, and water vapor obtained by evaporating the cooling water from a high-temperature slab. For this reason, when the volume in the bearing expands / shrinks due to fluctuations in the bearing temperature, there is a possibility that grease leakage in the bearing or suction of foreign matter from the outside may occur.

  However, in the rolling bearing 10A with the sealing device of the present invention, the elastic deformation portion 26 of the elastic seal body 22 is easily elastically deformed according to the internal pressure of the rolling bearing 10A with the sealing device, and absorbs this pressure fluctuation. The pressure inside the bearing is maintained at a substantially constant pressure. Thereby, the leakage of the lubricant accompanying the pressure variation in the bearing 10A and the entry of foreign matter from the outside are prevented, and the life of the bearing is prolonged.

  Further, when the slab passes over the roll, a large radial load also acts on the roll and the rolling bearing 10A that supports the roll, so that the sealing device 15 and the core metal 21 are deformed, and the function of the elastic deformation portion 26 is achieved. May be inhibited. However, since the cored bar 21 of the present embodiment includes the column part 25 that connects the outer peripheral side and the inner peripheral side, the deformation is prevented, and the elastic deformation part 26 stably stabilizes the pressure inside the bearing. Keep constant.

(Second Embodiment)
Next, a second embodiment of the rolling bearing with a sealing device according to the present invention will be described with reference to FIG. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals in the drawings, and description thereof is omitted or simplified.

  In the rolling bearing 10B with the sealing device of the present embodiment, as shown in FIG. 3, the sealing devices 30 that do not include the elastic deformation portions of the first embodiment are respectively provided at both axial ends between the outer ring 11 and the inner ring 12. A pressure adjusting hole 31 is formed at the center in the axial direction between the inner ring raceway grooves 12a and 12a of the inner ring 12 so as to penetrate in the radial direction. A plurality of the pressure adjusting holes 31 are formed in the circumferential direction of the inner ring 12, and the inner circumferential surface 12c of the inner ring 12 and the inner ring raceway groove 12a side communicate with each other. Further, an inner peripheral annular groove 32 communicating with the inner peripheral end of the pressure adjusting hole 31 is formed on the inner peripheral surface 12 c of the inner ring 12.

  In the rolling bearing 10B with the sealing device configured as described above, when the temperature of the bearing 10B rises and the pressure inside the bearing increases, the air inside the bearing is discharged to the outside of the bearing through the pressure adjustment hole 31, and the bearing 10B. When the temperature of the bearing decreases and the pressure inside the bearing decreases, the air outside the bearing is supplied into the bearing through the pressure adjustment hole 31. That is, air is taken in and out through the pressure adjusting hole 31 according to the pressure inside the bearing, and the pressure inside the bearing is maintained at a substantially constant pressure. Thereby, the sealing performance of the bearing 10B is enhanced, and leakage of the lubricant and entry of foreign matter from the outside are prevented. Further, a shaft (not shown) is fitted to the inner peripheral surface 12c of the inner ring 12, and the pressure adjusting hole 31 is arranged at the substantially center in the axial direction of the inner ring 12, so that even if the bearing has a negative pressure. No foreign matter will enter the bearing.

As described above, according to the rolling bearing 10B with the sealing device of the present embodiment, the pressure adjusting hole 31 that communicates the inside and the outside of the bearing 10B is formed through the radial direction in the center of the inner ring 12 in the axial direction. Therefore, the pressure inside the bearing can be maintained substantially constant by taking in and out the air inside the bearing through the pressure adjusting hole 31. As a result, the sealability of the bearing 10B can be improved, the leakage of the lubricant accompanying the pressure fluctuation inside the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended.
About another structure and an effect, it is the same as that of the said 1st Embodiment.

(Third embodiment)
Next, a third embodiment of the rolling bearing with a sealing device according to the present invention will be described with reference to FIG. Note that portions that are the same as or equivalent to those in the first and second embodiments are denoted by the same reference numerals in the drawings, and description thereof is omitted or simplified.

  In the rolling bearing 10C with a sealing device of the present embodiment, as shown in FIG. 4, an annular seal member 35 is mounted in the inner annular groove 32 of the inner ring 12 of the second embodiment. Is a sealing member formed in an annular shape by combining an elastic material such as rubber, a metal material, or an elastic material and a metal material, and is configured to be elastically deformable in accordance with the internal pressure of the bearing 10C.

  In the rolling bearing with a sealing device 10 </ b> C configured as described above, when the temperature of the bearing 10 </ b> C rises and the pressure inside the bearing increases, the annular seal member 35 is deformed in a direction of reducing the diameter in the inner circumferential annular groove 32. When the pressure rise is absorbed and the temperature of the bearing 10C decreases to reduce the pressure inside the bearing, the annular seal member 35 is deformed in the direction of expanding the diameter in the inner annular groove 32 to absorb the pressure drop. That is, the annular seal member 35 contracts or expands according to the pressure inside the bearing to absorb pressure fluctuations, and maintains the pressure inside the bearing at a substantially constant pressure. Thereby, the sealing performance of the bearing 10C is improved, and leakage of the lubricant and entry of foreign matter from the outside are prevented.

As described above, according to the rolling bearing 10C with the sealing device of the present embodiment, the annular seal member 35 that is elastically deformable according to the pressure inside the bearing is mounted in the inner circumferential annular groove 32 of the inner ring 12. Therefore, the pressure inside the bearing can be maintained substantially constant by reducing or expanding the diameter of the annular seal member 35. As a result, the sealing performance of the bearing 10C can be improved, the leakage of the lubricant accompanying the pressure fluctuation inside the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended. Moreover, since the annular seal member 35 is provided, the sealing performance can be improved as compared with the rolling bearing with a sealing device 10B of the second embodiment.
About another structure and an effect, it is the same as that of the said 1st and 2nd embodiment.

(Fourth embodiment)
Next, with reference to FIG. 5, 4th Embodiment of the rolling bearing with a sealing device which concerns on this invention is described. Note that the same or equivalent parts as those in the first and second embodiments are denoted by the same reference numerals in the drawings, and the description thereof is omitted or simplified.

  In the rolling bearing 10D with the sealing device of the present embodiment, as shown in FIG. 5, it penetrates radially in the center in the axial direction of the outer ring raceway groove 11a of the outer ring 11 (actually, the region where the roller 14 does not roll). A pressure adjusting hole 41 is formed in the bottom. A plurality of the pressure adjusting holes 41 are formed in the circumferential direction of the outer ring 11, and the outer peripheral surface 11c of the outer ring 11 communicates with the outer ring raceway groove 11a side. Further, an outer peripheral annular groove 42 communicating with the pressure adjusting hole 41 is formed on the outer peripheral surface 11 c of the outer ring 11.

  In the rolling bearing 10D with the sealing device configured as described above, when the temperature of the bearing 10D rises and the pressure inside the bearing increases, the air inside the bearing is discharged to the outside of the bearing through the pressure adjustment hole 41, and the bearing 10D. When the temperature of the bearing decreases and the pressure inside the bearing decreases, the air outside the bearing is supplied into the bearing through the pressure adjustment hole 41. That is, air is taken in and out through the pressure adjusting hole 41 in accordance with the pressure inside the bearing, and the pressure inside the bearing is maintained at a substantially constant pressure. Thereby, the sealing performance of the bearing 10D is improved, and leakage of the lubricant and entry of foreign matter from the outside are prevented. In addition, since the outer ring 11 is fitted in a housing (not shown) and the pressure adjusting hole 41 is arranged at the substantially center in the axial direction of the outer ring 11, even if the bearing has a negative pressure, foreign matter is not inside the bearing. There is no invasion.

As described above, according to the rolling bearing 10D with the sealing device of the present embodiment, the pressure adjusting hole 41 that communicates the inside and the outside of the bearing 10D is formed through the radial direction in the center of the outer ring 11 in the axial direction. Therefore, the pressure inside the bearing can be maintained substantially constant by taking in and out the air inside the bearing through the pressure adjusting hole 41. As a result, the sealability of the bearing 10D can be improved, the leakage of the lubricant accompanying the pressure fluctuation inside the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended.
About another structure and an effect, it is the same as that of the said 1st and 2nd embodiment.

(Fifth embodiment)
Next, a fifth embodiment of the rolling bearing with a sealing device according to the present invention will be described with reference to FIG. Note that the same or equivalent parts as those in the first and fourth embodiments are denoted by the same reference numerals in the drawings, and the description thereof is omitted or simplified.

  In the rolling bearing 10E with the sealing device of the present embodiment, as shown in FIG. 6, an annular seal member 45 is mounted in the outer circumferential annular groove 42 of the outer ring 11 of the fourth embodiment, and this annular seal member 45 is An elastic material such as rubber, a metal material, or a seal member formed in a ring shape by combining an elastic material and a metal material, and is configured to be elastically deformable in accordance with the internal pressure of the bearing 10E.

  In the rolling bearing 10E with the sealing device configured as described above, when the temperature of the bearing 10E rises and the pressure inside the bearing increases, the annular seal member 45 is deformed in the direction of expanding the diameter in the outer annular groove 42. When the pressure increase is absorbed and the temperature of the bearing 10E decreases to reduce the pressure inside the bearing, the annular seal member 45 is deformed in the direction of diameter reduction in the outer annular groove 42 to absorb the pressure decrease. That is, the annular seal member 45 expands or contracts in accordance with the pressure inside the bearing to absorb pressure fluctuations, and maintains the pressure inside the bearing at a substantially constant pressure. Thereby, the sealing performance of the bearing 10E is enhanced, and leakage of the lubricant and entry of foreign matter from the outside are prevented.

As described above, according to the rolling bearing 10E with the sealing device of the present embodiment, the annular seal member 45 that can be elastically deformed according to the pressure inside the bearing is attached to the outer circumferential annular groove 42 of the outer ring 11. The pressure inside the bearing can be maintained substantially constant by expanding or reducing the diameter of the annular seal member 45. As a result, the sealability of the bearing 10E can be improved, the leakage of the lubricant due to the pressure fluctuation inside the bearing and the entry of foreign matter from the outside can be prevented, and the bearing life can be extended. Moreover, since the annular seal member 45 is provided, the sealing performance can be improved more than the rolling bearing with a sealing device 10D of the fourth embodiment.
About another structure and an effect, it is the same as that of the said 1st and 4th embodiment.

In addition, this invention is not limited to what was illustrated by said each embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.
For example, in each of the above embodiments, a self-aligning roller bearing has been described as an example of a rolling bearing with a sealing device, but the present invention is not limited thereto, and self-aligning ball bearings, multi-row tapered roller bearings, multi-row cylindrical roller bearings, The present invention may be applied to a double row ball bearing or the like. The present invention can also be applied to a single row rolling bearing. In this case, the pressure adjusting hole is preferably formed at a position that does not interfere with the raceway surface, for example, at the shoulders of the inner ring and the outer ring.
In addition, depending on the rolling (continuous casting, hot rolling, cold rolling, multi-stage rolling, etc.), the bearing usage status (temperature, load, etc.) changes, so the first to fifth embodiments are combined depending on the type of rolling mill. It is possible.

DESCRIPTION OF SYMBOLS 10A Rolling bearing with a sealing device 10B Rolling bearing with a sealing device 10C Rolling bearing with a sealing device 10D Rolling bearing with a sealing device 10E Rolling bearing with a sealing device 11 Outer ring 11a Outer ring raceway groove 11b Inner circumferential surface 11c Outer ring surface 12 Inner ring raceway 12b Outer peripheral surface 12c Inner peripheral surface 14 Roller (rolling element)
15 Sealing device 21 Core metal 22 Elastic seal body 22a Seal lip (lip part)
24 long hole 25 column part 26 elastic deformation part 30 sealing device 31 pressure adjusting hole 32 inner circumferential annular groove 35 annular sealing member 41 pressure regulating hole 42 outer circumferential annular groove 45 annular sealing member

Claims (3)

A bearing having a metal core and an elastic seal body, which is fixed to one of the inner peripheral surface of the outer ring of the rolling bearing or the outer peripheral surface of the inner ring, and is slidably contacted with the other of the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. A sealing device for sealing the inside,
The core bar includes a first core bar extending in the radial direction and a second core bar extending in the radial direction,
The first metal core is formed in a ring shape having a substantially L-shaped cross section, and is formed between a plurality of holes provided on a side surface and extending along a circumferential direction, and the adjacent holes. A column connecting the outer peripheral side and the inner peripheral side of
The elastic sealing body includes a connecting portion that connects the first core metal and the second core metal, and a lip that is fixed to the second core metal and that is in sliding contact with the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. A thin-walled elastic deformation portion that is formed so as to close the hole and elastically deforms according to the pressure inside the bearing to maintain the inside of the bearing at a constant pressure ,
The said lip | rip part is urged | biased by the diameter reduction direction with a coil spring, The sealing device characterized by the above-mentioned .   2. The sealing device according to claim 1, wherein the circumferential length of the column portion is longer than the circumferential length of the hole. An outer ring having an outer ring raceway groove on an inner peripheral surface, an inner ring having an inner ring raceway groove on an outer peripheral surface, a plurality of rolling elements arranged to roll between the outer ring raceway groove and the inner ring raceway groove, and the outer ring A sealing device that is fixed to one of the inner peripheral surface of the inner ring and the outer peripheral surface of the inner ring, and that seals the inside of the bearing in sliding contact with the other of the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring. There,
Rolling said sealing device, characterized in that it is a sealing device according to claim 1 or 2.

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