JPH11342347A - Roller mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller mill in which its pulverizing capacity is maintained and the generation of vibration due to direct contact of a roller with a table is prevented by constituting an adjusting means for the clearance between the roller and the table so that it can be operated even during roller mill operation to sufficiently secure the clearance between the roller and the table on roller mill startup and stoppage and sufficiently coping with the wear of the roller and the table. SOLUTION: A table 3 is rotatably fitted to a driving shaft 2, and a roller 1 is arranged turned to the table 3 in a pressurized state. Material to be pulverized is put between the table 3 and the roller 1 to pulverize it to constitute a roller mill 10. A clearance adjusting means 6 is provided for energizing the roller 1 in the direction reverse to the pressurizing one of the roller 1 to prevent the direct contact between the table 3 and the roller 1. The clearance adjusting means 6 is provided with a driver 30 for enabling adjusting operation against pressurizing force of pressurizing the roller 1 against the table 3 even during roller mill 10 operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a roller mill,
More specifically, the present invention relates to a roller mill for pulverized coal-fired boilers in power plants and the like, or a roller mill for pulverizing limestone and clinker in the cement industry.

[0002]

2. Description of the Related Art As shown in FIG.
A table 3 rotatably attached to the drive shaft 2, a plurality of rollers 1 attached to the support shaft 11 toward the table 3 (one roller is illustrated in the figure), A load means 4 for pressing the roller 1 against the table 3 via the arm 7 is provided. The object 5 is sandwiched between the roller 1 and the table 3 on the table 3 and the object 5 is compressed and pulverized. Device.

Before starting the operation of the roller mill 10, the material 5 to be ground does not exist on the table 3,
Alternatively, when the roller mill 10 is started and stopped, the roller 1
And the table 3 come into direct contact. When the roller mill 10 is rotated in this state, a large vibration is generated. Therefore, in order to avoid the occurrence of such a phenomenon, a stopper 8 is provided as a gap adjusting means, and the adjustment is performed by manually applying a force in the opposite direction to the load means 4 to the roller 1 via the arm 7.

[0004]

However, the conventional roller mill 10 described above has the following problems. That is, in the conventional roller mill 10, since the adjustment by the stopper 8 can be performed only manually when the roller mill 10 is stopped as described above, it is difficult to perform the adjustment according to the operation state during the operation of the roller mill 10. Was.

In addition, the roller 1 and the table 3 are initially arranged with a predetermined gap G as shown in FIG. 3, but the roller 1 is worn out as shown by reference numeral 1a in FIG. The portion 1a is generated, and the table 3 also has the symbol 3
As shown by a, the roller 1 and the table 3 gradually wear due to wear over time, and the gap G gradually increases. Therefore, the position of the roller 1 during the operation of the roller mill 10 is
And gradually descend due to gravity.

Therefore, when the operation of the roller mill 10 is continued, the lower part of the arm 7 moves to the stopper side with the center shaft 20 as a fulcrum, and hits the stopper 8, causing the roller 1 to move.
Is hard to sufficiently act on the layer of the object 5 on the table 3, so that the grinding ability of the roller mill 10 is reduced. Therefore, it was necessary to stop the roller mill 10 periodically and adjust the position of the stopper 8.

On the other hand, when the stopper is not provided, it is not necessary to periodically adjust the position of the stopper. However, when starting and stopping the roller mill, the roller 1 and the table 3 come into direct contact with the load of the roller 1 being applied. Therefore, it is inevitable that a large vibration is generated and the mechanical life of a mechanical element such as a bearing is shortened.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem. By enabling the gap adjusting means to operate even during the operation of the roller mill, the roller and the table are started and stopped when the roller mill is started and stopped. To ensure sufficient clearance between the roller mill and the roller and table, and to maintain the crushing ability of the roller mill and to prevent the occurrence of vibration due to the direct contact between the roller and the table. A roller mill.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a roller mill, and is configured as follows to solve the above-mentioned technical problem. That is, the roller mill of the present invention includes a table rotatably attached to a drive shaft, and a roller arranged in a state capable of being pressed toward the table, and urges the roller with a predetermined pressing force. In a roller mill for crushing an object to be crushed between a table and a roller, a gap adjusting means for urging the roller in a direction opposite to the pressing direction of the roller to prevent direct contact between the table and the roller is provided. In addition, the driving force of the gap adjusting means is set to be larger than the pressing force urging the roller during the operation of the roller mill, and the adjusting operation of the gap adjusting means can be performed even during the operation of the roller mill. I do.

In the roller mill of the present invention, if the gap adjusting means exerts an effect of preventing direct contact between the roller and the table by biasing the roller in a direction opposite to the pressing direction of the roller, There is no particular limitation on its structure. However, even though the driving force of the gap adjusting means is set to be larger than the pressing force for urging the rollers during the operation of the roller mill, the driving device of the gap adjusting means is increased in size by using a linear cylinder or the like which performs linear motion. For ease of use, a stopper for adjusting the position of the roller is used, and the stopper is advanced / retracted by a combination of screw means and a rotary drive device such as an electric motor or a hydraulic motor. It is preferable to make the driving torque in the forward direction large while allowing the vehicle to retreat.

The gap adjusting means is provided with an appropriate sensor for detecting the gap between the roller and the table.
A stepping motor operated by a digital signal from a computer based on information from the sensor may be used.

Further, it is preferable that the biasing force for pressing the roller against the table is provided with a linearly moving load means such as a spring force or a hydraulic pressure.

[0013]

According to the roller mill of the present invention, since the driving force of the gap adjusting means is set to be larger than the pressing force for urging the roller during the operation of the roller mill, the driving force of the roller is reduced even during the driving operation of the roller mill. Contrary to this, the gap between the roller and the table can be maintained at a predetermined size by operating the gap adjusting means, and the occurrence of vibration due to the direct contact between the roller and the table can be suppressed. Also, during operation of the roller mill, the rollers and the table wear over time,
When the gap between the roller and the table becomes large, the driving device of the gap adjusting means operates to automatically adjust the gap suitable for the crushing of the object to be crushed to a desired value, thereby continuing the operation of the roller mill. . For this reason, the crushing of the object to be crushed is continuously performed without periodically stopping the operation of the roller mill and maintaining a constant clearance between the roller and the table.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a roller mill according to the present invention will be described in more detail with reference to an embodiment shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto, unless otherwise specified. It is only an illustrative example.

FIG. 1 shows a partial cross section of a main part of a roller mill according to one embodiment of the present invention, and FIG. 2 is a schematic explanatory view of the roller mill of this embodiment. .

Roller mill 10 according to an embodiment of the present invention
Comprises a table 3 rotatably mounted on a drive shaft 2. The table 3 has a bowl shape attached to the drive shaft 2 as shown in FIGS. Drive shaft 2
Is connected to a motor (not shown). Further, a plurality of rollers 1 (one roller is shown as a representative in the drawings) are arranged facing the table 3.

The rollers 1 are arranged on the table 3 with a predetermined gap G. The roller 1 is rotatably supported by a support shaft 11. That is,
A hub 13 is provided at the center of the roller 1, and the roller 1 is attached to a journal 11 a of a support shaft 11 via a bearing 12 incorporated in the hub 13. The support shaft 11 is fixed to the arm 7 and has a boss 14. A central shaft 20 fixed to the side of the outer wall 15 is inserted through a shaft hole 16 provided in the boss 14. I have.

Further, a load means 4 for pressing the roller 1 against the table 3 is provided. The load means 4 has a slider 18 movable in a direction indicated by an arrow A toward an arc-shaped projection 17 formed on an upper portion 7a of the arm 7, and a piston 21 for pressing a rear end of the slider 18. A hydraulic load device 19 is provided. The hydraulic load device 19 is a hydraulic cylinder as an actuator that performs a linear motion. The slider 18 is slidably incorporated in a sleeve 22 mounted in a through hole 23 formed in the outer wall 15.

Further, a roller 1 is provided on the lower arm 7b side.
Is pressed to swing the arm 7 in the direction opposite to the direction in which the roller 1 is pressed by the load means 4 via the central shaft 20, and a gap adjusting means 6 for preventing direct contact between the table 3 and the roller 1 is provided. . The gap adjusting means 6 includes a stopper 8 having an external thread formed on an outer wall of the roller wall 10 and having a screw shaft formed on an outer peripheral surface and having a spherical tip at a screw shaft. The stopper 8 is connected to the motor 3
0, and the motor 3 according to the state of the roller 1 and the table 3 during the operation of the roller mill 10.
By performing the forward / backward control while rotating the stopper 8 which is a screw shaft by the drive / stop control of 0, an adjustment operation is possible. In this case, the driving force of the motor 30 is such that the urging force, which is urged toward the lower arm 7b via the tip of the stopper 8 by the rotation of the stopper 8 which is a screw shaft, is the arc-shaped projection 17 formed on the upper arm 7a of the arm 7. The pressing force for pressing the roller 1 against the table 3 is set to be greater than the pressing force for pressing the roller 1 during operation of the roller mill by the hydraulic load device 19 via the slider 18. In addition, the driving force of the motor 30 is set so that the stopper 8 can be adjusted even during the operation of the roller mill.

Next, the operation of the embodiment of the present invention will be described. In order to crush the material 5 to be crushed by the roller mill 10, the roller 1 is initially pressed by the load means 4 and is in direct contact with the table 3. When the table 3 is rotated in this state, a large vibration is generated.

Then, when the motor 30 of the gap adjusting means 6 is rotated to rotate the stopper 8, the stopper 8 advances to the left along the screw hole 24 and presses the lower portion 7b of the arm 7 while rotating. Then, the arm 7 is swung about the center axis 20 as a fulcrum, and the upper part 7a of the arm 7 is moved rightward against the pressing direction of the load means 4. For this purpose, arm 7
The support shaft 11 fixed to the upper side moves up to sufficiently open the gap G between the roller 1 and the table 3. Next, after the table 5 is filled with the object 5 to be crushed, the motor 30 of the gap adjusting means 6 is reversely rotated to retract the stopper 8, and the object 5 is sandwiched between the roller 1 and the table 3.

In this state, the stopper 8 of the gap adjusting means 6 is retracted so that a sufficient pressing force is applied to the object 5 to be crushed, and then the drive shaft 2 is driven to rotate the table 3 to start a crushing step. . As shown in FIG. 3, the object 5 is compressed and pulverized while being sandwiched between the rotating roller 1 and the table 3. As the crushing process is continued, the material to be crushed 5 is crushed and its particle diameter gradually decreases, so that the crushed material layer becomes thinner, and the roller 1 and the table 3 gradually approach each other. Comes in direct contact.

In this state, a large vibration is generated.
Before the contact occurs, for example, the motor 3 of the gap adjusting means 6 is operated during the operation of the roller mill 10 by a feedback signal from a sensor (not shown) for detecting the gap G.
0 automatically operates to rotate the stopper 8 to advance the stopper 8 against the pressing force of pressing the roller 1 against the table 3 and to move the center shaft 20 against the pressing force of the load means 4. The support shaft 11 is raised as a fulcrum. For this reason,
Grinding is performed while keeping the gap G between the roller 1 and the table 3 constant. When a predetermined particle size is reached, the material to be crushed is discharged by airflow.

On the other hand, during the running operation of the roller mill 10, the load of the roller 1 is abraded temporally as shown in FIG.
Becomes larger (Ga), the motor 30 of the gap adjusting means 6 is operated by a feedback signal from a sensor (not shown), and the roller mill is operated while retracting the stopper 8 to adjust the gap to be suitable for the pulverization of the object 5 to be pulverized. Continue driving.

According to the roller mill according to the embodiment of the present invention, since the motor 30 is used as a driving device of the gap adjusting means 6 for urging the roller 1 in a direction opposite to the pressing direction of the roller 1, the operation of the roller mill 10 is operated. The adjustment operation can be automatically performed even during the operation, and it is possible to reliably suppress the occurrence of vibration due to the direct contact between the roller 1 and the table 3 when the roller mill 10 is started and stopped. Therefore, there is no need to periodically stop the roller mill 10 and adjust the position of the stopper 8, and the crushing operation can be performed efficiently.

Further, a motor 30 is used as a driving means of the gap adjusting means 6, and the stopper 8 rotated and driven by the motor 30 forms a pair of screws, so that the advance / retreat of the stopper 8 can be finely adjusted. , High-precision adjustment is possible.

[0027]

As described above, according to the roller mill of the present invention, the roller 1 is provided to the gap adjusting means for preventing direct contact between the roller pressing the roller in the direction opposite to the roller pressing direction and the table. A drive device that can be operated even during operation of the roll mill is provided in opposition to the pressing force of pressing the roller 3. Therefore, a) When starting and stopping the roller mill, vibration caused by direct contact between the roller and the table is automatically detected. It becomes possible to suppress. b) There is no need to stop the roller mill periodically to adjust the position of the gap adjusting means, and continuous grinding can be performed, and efficient grinding can be realized. c) The adjustment of the gap caused by the wear of the roller and the table can be automatically performed. This has the effect.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a main part of a roller mill according to an embodiment of the present invention.

FIG. 2 is a schematic explanatory view of a roller mill of the present embodiment.

FIG. 3 is an enlarged explanatory view of an opposing portion between a roller and a table.

FIG. 4 is an enlarged explanatory view of an opposing portion between the roller and the table, showing a worn portion generated on the roller and the table.

FIG. 5 is a schematic explanatory view of an example of a conventional roller mill.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Roller 2 Drive shaft 3 Table 5 Pulverized object 6 Skimmer adjustment means 10 Roller mill 30 Drive unit (motor) G Skimmer

Claims (1)

[Claims] 1. A table rotatably mounted on a drive shaft, and a roller disposed so as to be able to be pressed toward the table, and a predetermined pressing force is applied to the roller to cause the table and the roller to rotate. In a roller mill that sandwiches and grinds an object to be pulverized, with a gap adjusting means for urging the roller in a direction opposite to the pressing direction of the roller to prevent direct contact between the table and the roller, A roller mill, wherein a driving force of the gap adjusting means is set to be larger than a pressing force for urging the roller during a roller mill operation, and the gap adjusting means can be adjusted even during the roller mill operation.