JP6104788B2 - Roller bearing device and vertical mill - Google Patents

Description

  The present invention relates to a roller bearing device and a vertical mill used for a pulverizing roller for pulverizing solids such as coal and biomass.

  In combustion facilities such as boiler power generation, solid fuel such as coal or biomass is used as fuel. When this coal or the like is used as a solid fuel, for example, raw coal is pulverized by a vertical mill to generate pulverized coal, and the obtained pulverized coal is used as fuel.

  The saddle type mill includes a crushing roller disposed in a lower portion of a housing so that a crushing table can be driven and rotated and a crushing load can be applied. Therefore, when raw coal is supplied from the coal supply pipe onto the pulverization table, it is dispersed over the entire surface by centrifugal force to form a coal layer, and pulverized by pressing each pulverization roller against this coal layer. The pulverized coal after pulverization is dried by the supply air, classified and discharged to the outside. Examples of such vertical mills include those proposed in Patent Documents 1 and 2 below.

JP 09-047680 A Japanese Patent Laid-Open No. 2001-017880

By the way, when finely pulverizing coal with a pulverizing roller used in a vertical mill for pulverizing coal, grooves are formed on the inner surface of the bearing or the outer surface of the support shaft in order to prevent finely pulverized dust from entering the bearing device. doing.
Therefore, in such a bearing device, in addition to the original lubrication, the grease is also required to fill the gap around the shaft and seal the intrusion of dust such as pulverized pulverized coal.
Furthermore, in actual use, it is considered that the grease in the gap can be replaced by adding new grease, and foreign matter such as pulverized coal that has entered can be discharged to the outside.
Here, when supplying grease to the bearing and performing lubrication or the like, it is necessary to supply the grease uniformly even at a distance from the grease supply unit in order to make the grease supply uniform.

However, in the case of simple supply of grease, there are the following problems.
Use extra grease for filling the grease groove.
The grease that passes through the grease groove only passes through and does not contribute to lubrication.
Grease cannot be forcibly supplied to the gap.

  In view of the above problems, an object of the present invention is to provide a roller bearing device and a vertical mill that can efficiently supply grease to a lubricating surface with a small amount of grease used.

A first invention of the present invention for solving the above-described problems includes a support shaft that supports a pulverizing roller that pulverizes an object to be crushed, a bearing that supports the support shaft, and the support shaft and the bearing. A grease supply portion that supplies grease to the gap, and the grease is supplied, and the cross-sectional shape of the grease supply groove formed on one or both of the outer peripheral surface of the support shaft and the inner peripheral surface of the bearing is half In addition to the circular or semi-elliptical shape, the groove cross-sectional area is set so that the “cross-sectional area L” of the grease supply groove is directed to the side away from the grease supply side according to the function of equation (1) in It is in the roller bearing device characterized in that it is reduced. Here, as shown in FIG. 4, in equation (1), L is the cross-sectional area of the grease supply groove, d is the distance, d ₀ is the position on the grease discharge side, and d _i is the position on the grease supply side.

According to the present invention, the cross-sectional area of the groove is reduced according to the passage distance of the grease, so that the amount of grease that can pass is reduced and the grease enters the lubricating surface, so that the grease is reliably supplied to the entire bearing. Is done. By reducing the cross-sectional area of the grease supply groove at a constant ratio, a predetermined amount of grease can be stably supplied to each location.

According to a second aspect of the present invention, there is provided the roller bearing device according to the first aspect , wherein the grease supply groove has a throttle portion in a part thereof.

  According to the present invention, it is possible to increase the supply amount of grease at a target position by providing the throttle portion.

According to a third aspect of the present invention, there is provided the roller bearing device according to the first or second aspect, wherein the end portion of the grease supply groove is interrupted in the middle of the inner surface.

  According to the present invention, since the grease groove disappears in the middle, all the supplied grease can be discharged into the gap and used without waste.

According to a fourth aspect of the present invention, there is provided the roller bearing device according to any one of the first to third aspects, wherein the grease supply unit is located on the side of the grinding roller.

  According to the present invention, since the grease supply section is provided on the side of the pulverizing roller where there is a lot of dust, the intrusion of the pulverized material can be reliably sealed.

The fifth aspect of the invention is a housing having a hollow shape, a pulverizing table supported rotatably at a lower portion in the housing with a rotation axis along the vertical direction, and disposed above the pulverizing table, A crushing roller rotatably supported by a bearing device of any one of the first to fourth rollers, and a rotary classifier provided at an upper part in the housing and capable of classifying a pulverized product. It is in a vertical mill.

  According to the present invention, since it is used as a bearing means for a grinding roller of a vertical mill with a large amount of dust of pulverized material, the intrusion of the pulverized material can be reliably sealed and pulverized stably over a long period of time. .

According to the present invention, the grease supply groove is gradually or stepwise reduced at least one of the groove diameter, groove depth, or groove cross-sectional area from the grease supply side to the grease discharge side. Grease enters the gap and can be efficiently supplied to the lubricated surface.
Moreover, even if the groove length is the same as in the conventional case, the grease supply volume is reduced, so that the amount of grease used and the amount not effectively used can be reduced.
Since the grease supply pressure loss can be reduced, a sufficient amount of grease can be supplied to the bearing gap even when the width of the grease supply groove is increased.

FIG. 1 is a schematic diagram of a roller bearing device according to a first embodiment. FIG. 2 is a diagram illustrating a change in dimension of the grease supply groove according to the first embodiment. FIG. 3 is a schematic view of another roller bearing device according to the first embodiment. FIG. 4 is a diagram illustrating a change in the cross-sectional area of another grease supply groove according to the first embodiment. FIG. 5 is a schematic diagram of a roller bearing device according to a second embodiment. FIG. 6 is a schematic diagram of a roller bearing device according to a third embodiment. FIG. 7 is a schematic diagram of a roller bearing device according to a fourth embodiment. FIG. 8 is a schematic diagram of a roller bearing device according to a fifth embodiment. FIG. 9 is a schematic configuration diagram illustrating a vertical mill according to an embodiment of the present invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

FIG. 1 is a schematic diagram of a roller bearing device according to a first embodiment. FIG. 2 is a diagram illustrating a change in dimension of the grease supply groove according to the first embodiment.
First, an example of a vertical mill to which the roller bearing device of this embodiment is applied is shown in FIG. FIG. 9 is a schematic configuration diagram illustrating a vertical mill according to an embodiment of the present invention. As shown in FIG. 9, the vertical mill 10 grinds solid materials such as coal (raw coal) and biomass. Here, biomass refers to organic resources derived from renewable organisms, such as thinned wood, waste wood, driftwood, grass, waste, sludge, tires, and recycled fuel (pellets and chips) made from these raw materials. ) And the like, and is not limited to those presented here.

  In the vertical mill 10 of the present embodiment, as shown in FIG. 9, the housing 11 has a cylindrical hollow shape, and a coal supply pipe 12 is mounted on the top. The coal supply pipe 12 supplies coal into the housing 11 from a coal supply device (not shown). The coal supply pipe 12 is arranged at the center position of the housing 11 along the vertical direction (vertical direction), and the lower end portion extends downward. Has been.

  The housing 11 has a crushing table 13 disposed at the bottom. The crushing table 13 is disposed at the center position of the housing 11 so as to face the lower end portion of the coal supply pipe 12. Further, the crushing table 13 is connected to a lower portion of a rotating shaft 14 having a rotation axis along the vertical direction, and is rotatably supported by the housing 11. A worm wheel 15 as a drive gear is fixed to the rotary shaft 14, and a worm gear 16 of a drive motor (not shown) mounted on the housing 11 is engaged with the worm wheel 15. Therefore, the crushing table 13 can be driven to rotate by the drive motor via the worm gear 16, the worm wheel 15, and the rotating shaft 14.

  The crushing table 13 has a ring-shaped table liner 17 fixed to the outer peripheral side. The table liner 17 has an inclined surface whose surface (upper surface) becomes higher as it goes to the outer peripheral side of the crushing table 13. A plurality of crushing rollers 18 are arranged facing the upper side of the crushing table 13 (table liner 17), and a roller driving device 19 for driving and rotating each crushing roller 18 is provided. The roller driving device 19 is a motor, for example, and can apply a driving force to the crushing roller 18.

  That is, the rear end portion of the support shaft 51 is supported by the roller drive device 19, and the roller drive device 19 is supported by the mounting shaft 22 on the side wall portion of the housing 11, so that the tip end portion of the support shaft 51 is vertically moved. It can swing in the direction. The support shaft 51 is disposed such that the tip thereof faces the rotational axis direction of the crushing table 13 and is inclined downward, and the crushing roller 18 is mounted.

  Further, the roller drive device 19 is provided with an upper arm 24 that extends upward, and a distal end portion of a pressing rod 26 of a hydraulic cylinder 25 as a pressing device fixed to the housing 11 is connected to a distal end portion of the upper arm 24. ing. The roller driving device 19 (support shaft 51) is provided with a lower arm 27 extending downward, and a tip portion thereof can come into contact with a stopper 28 fixed to the housing 11. Therefore, when the pressing rod 26 is advanced by the hydraulic cylinder 25, the upper arm 24 is pressed, and the roller driving device 19 and the support shaft 51 can be rotated in the clockwise direction in FIG. . At this time, when the lower arm 27 abuts against the stopper 28, the rotational positions of the roller driving device 19 and the support shaft 51 are defined.

  That is, the crushing roller 18 crushes coal with the crushing table 13 (table liner 17), and a predetermined gap is provided between the surface of the crushing roller 18 and the surface of the crushing table 13 (table liner 17). It is necessary to secure. Therefore, by defining the support shaft 51 at a predetermined rotation position by the hydraulic cylinder 25, a predetermined gap is secured between the surface of the crushing roller 18 and the surface of the crushing table 13 so that coal can be taken in and pulverized. The

  In this case, when the crushing table 13 rotates, the coal supplied onto the crushing table 13 is moved to the outer peripheral side by the centrifugal force and enters between the crushing roller 18 and the crushing table 13. Since the crushing roller 18 is pressed toward the crushing table 13, the rotational force of the crushing table 13 is transmitted through the coal, and the crushing roller 18 can rotate in conjunction with the rotation of the crushing table 13. .

  In the present embodiment, the crushing roller 18 has a truncated cone shape with a small diameter on the tip side and the surface of the crushing roller 18 is flat. However, the present invention is not limited to this shape. For example, the grinding roller 18 may have a tire shape. In the present embodiment, a plurality of (three) crushing rollers 18 are provided and arranged at equal intervals along the rotation direction of the crushing table 13. In this case, the number and arrangement of the crushing rollers 18 may be appropriately set according to the size of the crushing table 13, the crushing roller 18, and the like.

  In addition, the housing 11 is provided with an inlet port 31 at the lower part located on the outer periphery of the crushing table 13 and into which primary air is fed. In addition, the housing 11 is provided with an outlet port 32 for discharging pulverized coal (pulverized coal) located on the outer periphery of the coal supply pipe 12 at the upper part. The housing 11 is provided with a rotary separator 33 as a rotary classifier for classifying pulverized coal below the outlet port 32. The rotary separator 33 is provided on the outer periphery of the coal supply pipe 12 and can be driven and rotated by a drive device 34. In addition, the housing 11 is provided with a foreign matter discharge pipe 35 at the bottom. The foreign matter discharge pipe 35 is for discharging foreign matters (spillage) such as gravel and metal pieces mixed in coal by dropping from the outer peripheral portion of the crushing table 13.

  Here, the roller bearing device 50A of the present embodiment is provided in the roller driving device 19, and supports the support shaft. Hereinafter, the roller bearing device 50A of the present embodiment will be described in detail.

  As shown in FIG. 1, a roller bearing device 50 </ b> A according to the first embodiment includes a support shaft 51 that supports a grinding roller 18 that grinds an object to be ground, a bearing 52 that supports the support shaft 51, and grease 53. Is supplied, and the grease supply groove 55 formed in a spiral shape on the outer peripheral surface of the support shaft 51 (or the inner peripheral surface of the bearing 52) has its groove width and groove toward the side away from the supply side of the grease 53. At least one of the depth and the groove cross-sectional area is reduced gradually or stepwise.

In the present embodiment, the groove width of the grease supply groove 55 is gradually reduced as shown in FIG. 2 toward the side away from the supply side of the grease 53.
In the roller bearing device 50B according to another embodiment of the first embodiment, the grease supply portion 54 of the grease supply groove 55 is used as a starting point on the grease supply side (grinding roller 18 side) in the groove forming length (distance) direction. The size of the groove width is gradually reduced.

  As a result, the structure is such that the cross-sectional area of the grease supply groove 55 through which the grease 53 passes is gradually reduced according to the distance from the grease supply portion 54, so that the amount of grease 53 that can pass through is reduced and the leaked grease 53 penetrates into the lubrication surface of the gap S, so that the grease is reliably supplied to the entire bearing. Thereby, the sealing performance of the pulverized material at the pulverizing roller can be improved.

  Therefore, since the volume of the groove is reduced, the amount of grease used is reduced. Furthermore, the amount of grease that does not contribute to lubrication simply by passing through as in the conventional case is also reduced.

  Here, in this embodiment, the grease supply groove 55 is formed on the inner peripheral surface of the bearing 52. However, the present invention can also be applied to the case where it is provided on one or both of the outer peripheral surfaces on the support shaft 51 side.

Here, as a structure for reducing the cross-sectional area of the grease supply groove 55, a structure for reducing the groove width and the groove depth is applied.
Further, when the width and depth of the groove are changed at the same time, the groove width and depth may be changed at the same ratio and at different ratios.

  Further, when the cross-sectional shape of the groove is, for example, a semicircular shape or a semi-elliptical shape, the groove diameter can be reduced.

  Here, if the cross-sectional area of the groove is semicircular or semi-elliptical, if the groove diameter is simply reduced at a constant ratio, the cross-sectional area decreases by the square of the diameter, so that a lot of grease is discharged near the grease supply section. As a result, on the grease discharge side, the supply amount of new grease decreases, and the sealing performance deteriorates.

Therefore, in order to uniformly supply the grease, it is desirable that the area decreases at a constant rate, if reducing the radius, the formula of the "cross-sectional area L" of the grease supply groove, following the "number 2" ( By reducing the cross-sectional area of the grease supply groove 55 at a constant ratio in accordance with the function of 1) , a predetermined amount of grease can be stably supplied to each location. That is, as shown in FIG. 4, although the reduction ratio of the cross-sectional area is small on the grease supply section 54 side, a certain amount of grease is reliably supplied to each place by increasing the reduction ratio as it goes to the grease discharge side. Will be. Here, as shown in FIG. 4, in equation (1), L is the cross-sectional area of the grease supply groove, d is the distance, d ₀ is the position on the grease discharge side, and d _i is the position on the grease supply side.

  According to this embodiment, at least one of the groove diameter, groove depth, or groove cross-sectional area of the grease supply groove 55 from the grease supply part 54 side of the grease 53 toward the grease discharge side is gradually or stepwise. Therefore, the grease can enter the gap and efficiently supply the grease to the lubricating surface.

  Moreover, even if the groove length is the same as in the conventional case, the grease supply volume is reduced, so that the amount of grease used and the amount not effectively used can be reduced.

  Furthermore, since the pressure loss of the grease supply can be reduced, a sufficient amount of grease can be supplied to the bearing gap even when the width of the grease supply groove is widened.

  In the present embodiment, the support shaft 51 is inserted into the bearing 52. However, the present invention is not limited to this. For example, if the sleeve is fastened to the support shaft 51 and the bush is spaced from the bearing 52, the present invention is not limited thereto. Thus, the grease supply groove may be formed inside the bush or the outside of the sleeve.

  Further, when the mounting shaft 22 is arranged to penetrate from the inside of the mill to the outside, a grease supply groove similar to the bearing 52 of the main shaft of the grinding roller 18 may be formed.

Next, a roller bearing device according to a second embodiment will be described.
FIG. 5 is a schematic diagram of a roller bearing device according to a second embodiment. In addition, the same code | symbol is attached | subjected to the member which overlaps with the structure of the roller bearing apparatus based on Example 1, and the description is abbreviate | omitted.
In the roller bearing device 50C according to the present embodiment, as shown in FIG. 5, the groove width of the grease supply groove 55 is constant at a predetermined distance, and in this embodiment, the groove diameter is reduced at a constant ratio in three stages. I try to let them.

Where it is necessary to supply a large amount of grease 53, the amount of grease supply can be increased by increasing the reduction rate of the cross-sectional area.
At the bearing end, there is a certain amount of supply due to the ingress of grease from the end face. Can be improved. In particular, on the pulverizing roller 18 side, the sealing effect due to the bleeding of the grease 53 is improved due to the necessity of sealing the intrusion of the pulverized material.

  According to the present embodiment, the grease supply groove 55 is sequentially reduced in steps, so that the protrusion of the grease can be increased and the supply amount at that portion can be increased.

Next, a roller bearing device according to a third embodiment will be described.
FIG. 6 is a schematic diagram of a roller bearing device according to a third embodiment. In addition, the same code | symbol is attached | subjected to the member which overlaps with the structure of the roller bearing apparatus based on Example 1, and the description is abbreviate | omitted.
In the roller bearing device 50D according to the present embodiment, as shown in FIG. 6, the grease supply groove 55 has a tapered portion 58 on the end side in the grease flow direction of a predetermined length.

  In the present embodiment, as in the second embodiment, in order to prevent the grease supply groove 55 from suddenly decreasing in a stepwise manner, a tapered portion 58 is provided in the first portion that decreases in a stepwise manner. By providing the taper portion 58 and smoothing it, the stay of the grease 53 in the corner portion can be suppressed.

  Since the viscosity of the portion where the shearing (shearing) is not applied increases, the grease 53 becomes more difficult to flow with the passage of time once it is retained. As a result, the accumulated grease sticks and causes troubles. To eliminate this, the tapered portion 58 is provided, and the grease supply groove 55 is smoothly narrowed to prevent the grease from staying. be able to.

Next, a roller bearing device according to Embodiment 4 will be described.
FIG. 7 is a schematic diagram of a roller bearing device according to a fourth embodiment. In addition, the same code | symbol is attached | subjected to the member which overlaps with the structure of the roller bearing apparatus based on Example 1, and the description is abbreviate | omitted.
In the roller bearing device 50E according to the present embodiment, as shown in FIG.

By forming the throttle portion 59 in a part of the grease supply groove 55, the supply amount of the grease 53 can be increased at the target position.
In post-processing after forming the groove, it is possible to fit a jig of the drawn portion 59 created separately and fix it by adhesion or welding, etc., and overlaying etc. can also be applied, making it easy to manufacture is there. In addition, it can also be installed in an existing grease supply groove by post-processing.

Accordingly, the amount of grease supply can be increased by providing the throttle portion 59 where it is necessary to supply a large amount of grease 53 and increasing the reduction rate of the cross-sectional area.
Further, since a certain amount of grease is supplied at the end of the bearing due to the ingress of grease from the end face, the grease groove may be squeezed to release the grease when the grease starts to break.

  According to the present embodiment, the supply amount of grease can be increased at the target position by providing the throttle portion.

Next, a roller bearing device according to Embodiment 5 will be described.
FIG. 8 is a schematic diagram of a roller bearing device according to a fifth embodiment. In addition, the same code | symbol is attached | subjected to the member which overlaps with the structure of the roller bearing apparatus based on Example 1, and the description is abbreviate | omitted.
In the roller bearing device 50F according to the present embodiment, in the roller bearing device according to the first embodiment, the end portion of the grease supply groove 55 becomes the disappearing portion 60 in the middle of the inner surface, and is interrupted.

  By reducing the cross-sectional area of the grease supply groove 55 to 0 and disappearing in the middle, all the grease 53 is discharged into the gap S at that time and can be used up for lubrication.

  According to the present embodiment, since all the grease 53 can be finally discharged from the grease supply groove 55, it can be used without waste.

  Therefore, by using the vertical mill 10 to which the roller driving device 19 using the roller bearing device according to the present embodiment is applied, for example, it is used as a bearing unit for a grinding roller having a large amount of dust of the crushed material. And can be pulverized stably over a long period of time.

10 Vertical Mill 50A-50F Roller Bearing Device 51 Support Shaft 52 Bearing 53 Grease 54 Grease Supply Portion 55 Grease Supply Groove S Clearance

Claims (5)

A support shaft that supports a pulverizing roller that pulverizes the object to be crushed, a bearing that supports the support shaft, and a grease supply unit that supplies grease to a gap between the support shaft and the bearing,
The grease is supplied, and the cross-sectional shape of the grease supply groove formed on one or both of the outer peripheral surface of the support shaft and the inner peripheral surface of the bearing is semicircular or semielliptical,
A roller characterized in that the groove cross-sectional area is reduced by reducing the “cross-sectional area L” of the grease supply groove toward the side away from the grease supply side in accordance with the function of equation (1) of the following “Equation 1”. Bearing device.
In Equation (1), L is a cross-sectional area of the grease supply groove, d is a distance, d ₀ is a position on the grease discharge side, and d _i is a position on the grease supply side.

Oite to claim 1,
A roller bearing device having a throttle portion in a part of the grease supply groove. Oite to claim 1 or 2,
A roller bearing device, wherein the end portion of the grease supply groove is interrupted in the middle of the inner surface. In any one of Claims 1 thru | or 3 ,
The roller bearing device, wherein the grease supply section is located on the side of the grinding roller. A hollow housing;
A pulverization table supported so as to be capable of driving and rotating with a rotation axis along the vertical direction at a lower portion in the housing;
A pulverizing roller that is disposed to oppose the pulverizing table and is rotatably supported by a roller bearing device according to any one of claims 1 to 4 .
A rotary classifier provided at an upper part in the housing and capable of classifying pulverized material;
A vertical mill characterized by comprising:

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