JPH05345138A - Gap control device of vertical mill - Google Patents

Abstract

PURPOSE:To prevent the lowering of grinding capacity, the restriction of a grinding load range and the excessive vibration at the time of low load by pressing the control jig operated by a control cylinder to the lower end part of the roller support material tiltable around a support shaft to receive the tilting movement of the roll support material and controlling the gap between a roller and a turntable. CONSTITUTION:The control jig 36 operated by a control cylinder 38 is pressed to the lower end part of the roller support material 16 tiltable around a support shaft 18 to receive the tilting movement of the roller support material 16 and the gap between a roller 14 and a turntable 12 is controlled. Since the pressure of the roller support material 16 is always received by the positioning due to the control jig 36 of the control cylinder 38 when the gap is contracted by the tilting movement of the roller support material 16 due to the advance of the abrasion of the roller 14, the control of the gap under sudden contact is eliminated and the thickness of a grinding layer can be held to the optimum state and the lowering of grinding capacity, the restriction of a grinding load range and the excessive vibration at the time of low load can effectively be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gap adjusting device for a vertical mill for pulverizing crushed material such as coal, and particularly for improving the pulverizing performance in a wide load range by adjusting the gap between a roller and a rotary table. The present invention relates to a gap adjusting device for a vertical type mill.

[0002]

2. Description of the Related Art Conventionally, as a gap adjusting device for a vertical mill, as shown in FIG.
The structure is such that the gap between the roller 14 and the rotary table 12 can be adjusted by adjusting the adjusting bolt 22 at the lower end side of the.

In FIG. 3, the vertical mill 10 includes rollers 14
A crushing portion is formed by the rotary table 12, and 18 is a support shaft, and the roller support member 16 supporting the roller 14 is tiltable around the support shaft 18. The upper end portion of the roller support member 16 is pressed and the roller 14 inserts the crushing layer into the rotary table 1.
It is designed to pressurize 2. Then, the adjusting bolt 22 is adjusted so that the roller 14 is operated with the minimum gap set so as not to bring the roller 14 into direct contact with the rotary table 12.

The roller 14 is driven by the rotation table 12 being driven.
Is driven, and the coal, which is the crushing material 32, passes through the coal feeding pipe downwardly to reach the crushing section, and under the introduction of the hot gas 24 in the crushing layer formed in the gap between the roller 14 and the rotary table 12. The powder is crushed by the action of the compressive force and the shearing force, rises in the casing together with the air flow, passes through the rotary classifier 30 and is separated into fine powder and coarse powder. Transferred to the process. The coarse powder is returned to the crushing chamber and crushed again.

When the vertical mill 10 is continuously operated for a long period of time, the rollers 14 and the rotary table 12 are abraded, especially the rollers 14 are abraded, so that the gap is increased and the pulverization is performed under a thick pulverized layer. Since the transmission of the compressive force and the shearing force is reduced and the crushing performance is reduced if the above is continued, there is an upper limit of the gap. When the wear of the roller 14 significantly progresses as described above, the pressure member 20 is pressed to reduce the gap, and the roller support member 16 is pressed.
The vertical mill 10 is continuously operated with the roller 14 tilted and the roller 14 moved downward. Further roller support 16
When the tilting is continued, the lower end side portion of the roller support member 16 comes into contact with the adjusting bolt 22, and when the vertical mill 10 is operated in this state, the gap is reduced. There is a lower limit for the gap as it is ground under a thin grinding layer resulting in a contact state similar to direct contact and causing excessive vibration in the vertical mill 10. Then, the adjustment bolt 22 and the pressing member 20 are adjusted so as to avoid reaching the lower limit.

Conventionally, a gap measuring device for a vertical mill has been known, but a device for automatically adjusting the gap between a roller and a rotary table has not been proposed (JP-A-63-63).
-278651).

[0007]

However, the above-mentioned conventional structure is effective for adjusting the gap between the roller and the rotary table. However, when the wear of the roller progresses, the roller support member is tilted and the above-mentioned structure is used. If the gap is reduced, excessive vibration is generated in the vertical mill, so that the vertical mill is operated within the lower limit, which may limit the crushing load range of the vertical mill, which is not preferable.

The present invention has been made to solve the above-mentioned problems, and its purpose is to reduce the crushing performance by keeping the gap between the roller and the rotary table, that is, the crushing layer thickness in an optimum state. An object of the present invention is to provide a vertical mill gap adjusting device that can effectively prevent excessive vibration from occurring when the vertical mill has a restricted crushing load range and a low load.

[0009]

In order to achieve such an object, the present invention is a gap adjusting device for adjusting a gap between a roller of a vertical mill and a rotary table, which is tiltable around a spindle. It is characterized in that an adjusting tool operated by an adjusting cylinder is pressed against the lower end side of the roller supporting member to receive the tilting movement of the roller supporting member and adjust the gap between the roller and the rotary table.

[0010]

With this arrangement, when the roller wear advances and the roller support member tilts to reduce the gap, the roller support member is constantly pressured by the positioning by the adjusting tool of the adjusting cylinder. It is possible to keep the crushing layer thickness in an optimum state by eliminating the gap adjustment under various contact conditions, and effectively prevent the deterioration of the crushing performance, the restriction of the crushing load range, and the occurrence of excessive vibration under low load. Further, the crushing layer thickness is adjusted by detecting the rotation angle of the support shaft of the roller support and performing the gap adjustment by the control unit that performs feedback control based on the crushing characteristics of the vertical mill based on the above-mentioned gap, so that the optimum crushing operation can be performed. It can be performed.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a main part of a gap adjusting device for a vertical mill showing an embodiment of the present invention, FIG. 2 is an explanatory view for explaining the operation of the embodiment of the present invention, and members shown in FIG. The same members as those in FIG.

In FIGS. 1 and 2, the lower end side portion 17 of the roller support member 16 forms a stopper and has an adjusting cylinder 38 having an adjusting tool 36 for pressing the lower end side portion 17.
Is attached to the cover 27 of the casing 26. The adjusting cylinder 38 is a hydraulic pump 4 forming a hydraulic circuit.
6, operated by the action of the servo valve 42, the accumulator 40, and the like.

Reference numeral 48 is a detection means for detecting the rotation angle of the support shaft 18 of the roller support member 16, and a proximity sensor such as a magnetic sensor or a visual sensor is suitable. The detection signal 49 from the detection means 48 is input to the control unit 50 under the command value 52 to perform the required control operation, and the operation signal 51 is input to the servo valve 42 to act on the hydraulic circuit to drive the drive. The operation of the cylinder 38 is operated. The output signal 54 from the control unit 50 is used for higher-level control, for example, a signal for controlling the amount of coal supply and a signal for image processing.

In this way, the roller support member 16 is tilted by the operation of the pressure member 20 so that the lower end side portion 17 comes into contact with the positioned tip end position of the adjusting tool 36, and the roller 16 and the rotary table 12 are brought into contact with each other. Is determined. Then, the tip of the adjusting tool 36 is positioned by the operation of the adjusting cylinder 38, and the gap is also determined by inputting the command value 52 to the controller 50.

In FIG. 2 (a), when the vertical mill is started, the adjusting tool 3 is held so as to hold the gap G ₀ in order to prevent the roller 14 and the rotary table 12 from coming into direct contact with each other.
Roller support member 16 under the end position L ₀ of 6 centerline C
Tilted with L ₀ , the outer diameter D ₀ of the roller 14 has initial dimensions.

In FIG. 2 (b), the roller support 16 is positioned at the tip position L ₁ of the adjusting tool 36 so as to maintain the gap G ₁ during the steady operation of the vertical mill, and the roller support member 16 has the center line CL.
Tilt with ₁ . Outer diameter D of roller 14 at this time
₁ has explained the case where it has the initial dimension D ₀ .

In FIG. 2 (c), wear of the roller 14 progresses as the vertical mill is operated for a long time, the outer diameter D ₁ is smaller than the initial dimension D ₀ , and the gap G ₂ is smaller than the gap G ₁ . It also indicates that the vertical mill is pulverizing performance is deteriorated.

In FIG. 2D, an outer diameter D ₃ roller 1 having the same size as the outer diameter D _{2 in} the state shown in FIG. 2C.
No. 4 is positioned at the tip end position L ₃ of the adjusting tool 36 and the roller supporting member 16 is tilted with the center line CL ₃ in order to maintain the gap G ₃ so that good crushing performance can be obtained.

Referring again to FIG. 1, in the control unit 50, the crushing load factor of the vertical mill 10 and the gap G, that is, crushing is performed by crushing using the roller 14 and the rotary table 12 having the initial dimensions. Since the functional relationship with the layer thickness is given as a pre-determination standard by using the function generator, when the deviation between the detection of the rotation angle of the support shaft 18 and the detection of the functional relationship occurs, the command value 52 When the feedback control operation corresponding to the above is performed, that is, when the wear of the roller 14 progresses, the drive cylinder 38 operates and the gap G is automatically adjusted so as to reduce the gap G, and the vertical mill 1
With 0, the operation can be continued under the optimum grinding operation. Further, when the gap G approaches the lower limit and the occurrence of vibration increases during low load operation of the vertical mill, these vibration forces are accumulated in the hydraulic circuit from the roller support member 16 via the adjusting tool 36 and the adjusting cylinder 38. Therefore, low load operation can be performed without generating excessive vibration in the vertical mill 10 main body, and the crushing load range can be increased as compared with the prior art.

[0020]

As described above, according to the present invention,
When the wear of the roller progresses due to the long-time operation of the vertical mill and the roller support is tilted to reduce the gap, the roller support is constantly receiving pressure due to the positioning of the adjusting cylinder adjustment tool. Since the original gap adjustment is eliminated, the crushing layer thickness can be maintained in an optimum state, and it is possible to effectively prevent deterioration of the crushing performance, restriction of the crushing load range, and generation of excessive vibration at low load. Further, the thickness of the crushed layer is detected by detecting the rotation angle of the support shaft of the roller support material, and the gap is adjusted by the control unit that performs feedback control based on the crushing characteristic of the gap of the vertical mill as a reference. It is possible to perform a great effect.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a gap adjusting device of a vertical mill showing an embodiment of the present invention,

FIG. 2 is an explanatory view for explaining the operation of the embodiment of the present invention,

FIG. 3 is an overall configuration diagram of a conventional gap adjusting device for a vertical mill.

[Explanation of symbols]

 10 Vertical Mill 12 Rotating Table 14 Roller 16 Roller Supporting Material 18 Spindle 36 Adjusting Tool 38 Adjusting Cylinder 48 Detecting Means 50 Control Section

Claims (3)

[Claims] 1. A gap adjusting device for adjusting a gap between a roller of a vertical mill and a rotary table, wherein the adjusting tool is actuated by an adjusting cylinder on a lower end side of a roller supporting member which can be tilted around a support shaft. Is pressed to receive the tilting of the roller support material,
A clearance adjusting device for a vertical mill, which adjusts a clearance between a roller and a rotary table. 2. The gap adjusting device for a vertical mill according to claim 1, wherein the adjusting device adjusts a gap between the roller and the rotary table within a required range. 3. A detection means for detecting the rotation angle of the support shaft, and a control portion for adjusting the gap between the roller and the rotary table according to the detection signal. A gap adjusting device for a vertical mill according to item 2.