JP2800273B2 - Super calendar device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a super calendar device.

2. Description of the Related Art As shown in FIG. 4, a super calender device in a paper machine is provided with a number of metal rolls 1 and elastic rolls 2 rotating at a high speed, and a product (paper) is provided between the rolls 1 and 2. 3, the smoothness and glossiness of the product 3 are improved.

In the super calendar device, since many rolls 1 and 2 rotate at a high speed, vibration is apt to occur.
There is a problem that adversely affects the quality of the product.

For this reason, conventionally, the main frame 4, 4 is cast by casting so that the planar shape becomes a shape close to a square as shown in FIG.
4 with high rigidity, and between the left and right mainframes 4,
Each of the rolls 1 and 2 is supported via a bearing 6 so as to be connected by a tie beam 5 extending in the left-right width direction. In the figure, reference numeral 7 denotes an upper frame, and reference numeral 8 denotes a roll storage post for storing a replacement elastic roll 2 '.

[Problems to be Solved by the Invention] However, in the above-described conventional method, the main frame 4,
Since the plane shape of 4 is a shape close to a square and the rigidity is increased to reduce the vibration of the main frames 4 and 4, there is a problem that the shape becomes large and heavy, and as described above. in the longitudinal direction of the main frame 4, 4 due to the close dimensions (MD direction) and the lateral width direction (CD direction), MD direction of the natural frequency f _MD and CD directions of the natural frequency f
_{The CD} approaches as shown in FIG. 6 and, for this reason, one or both of the natural frequency f _{MD in the MD} direction and the natural frequency f _{CD in} the CD direction (f _{CD in the} illustrated example) fall within the operating speed range L. Therefore, during operation, the main frames 4, 4 resonate with the vibrating sources, such as the rolls 1, 2, etc., to generate vibrations, thereby causing problems such as deterioration of product quality and generation of noise.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and has as its object to provide a stable calendar operation by suppressing vibration of a super calendar device.

Means for Solving the Problems According to the present invention, in a super calendar device having a configuration in which left and right main frames are connected by tie beams extending in the width direction, an operation speed range is set, and a maximum operation in the operation speed range of the super calendar device is set. The length of the main frame in the front-rear direction is determined so as to have a second moment of area having a natural frequency greater than the vibration source frequency at the time of the speed, and at the time of the minimum operating speed in the operating speed range of the super calendar device. The thickness of the main frame in the width direction is determined so as to have a second moment of area having a natural frequency smaller than the vibration source frequency of the super calender.

[Operation] During operation of the super calendar device, the secondary moment of area in the front-rear direction of the main frame is determined so as to have a natural frequency greater than the vibration source frequency at the maximum operation speed, and the minimum operation speed Since the second moment of area in the width direction of the main frame is determined so as to have a natural frequency smaller than the vibration source frequency at that time, generation of vibration within the operating speed range is prevented.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

1 and 2 show an example of the present invention,
The planar shape of the main frames 9, 9 supporting a large number of metal rolls 1 and elastic rolls 2 via bearings 6 is determined in the width direction (CD
Longitudinal direction (MD direction) length to the direction) thickness b ₁
except that h ₁ is a much larger plate is substantially the same as the conventional super calender, the same operational member are denoted by the same reference numerals.

A method of determining the thickness in the width direction and the length in the front-rear direction of the main frames 9, 9 in the above configuration will be described below with reference to FIGS.

Rate of supercalenders i.e., the excitation source frequency f ₁ when the excitation source frequency f ₂ at the maximum rotational speed of the rolls 1 and 2 (Hz) of the minimum rotation speed (Hz), carried out at normal capacity As shown in Fig. 6, the maximum and minimum operating speed setting ranges are
Consider the case of 1000m / min vs. 500m / min as an example.

The operating speed range L can be set as follows.

(I) First, the setting of the rigidity of the main frames 9, 9 in the MD direction will be described.

Natural frequency (resonance point) in the MD direction of mainframe 9,9
Where (f _n ) _MD is the margin α for the source frequency f ₂ Set.

The second moment of area I _MD in the MD direction is b ₁ : Outer thickness dimension b ₂ : Inner thickness dimension h ₁ : Outer length dimension h ₂ : Inner length dimension Static deflection δ _{MD in} MD direction is w: Additional weight of roll + own weight of main frame (kg / c
m ² ) l: height of the main frame E: Young's modulus of the main frame (kg / cm ² ) Therefore, the natural frequency of the main frames 9, 9 in the MD direction (f
_n ) _MD g: The gravitational acceleration 980 cm / sec ² or the excitation source frequency f ₂ generated from the elastic roll 2 at the maximum operation speed is: Vmax: Maximum operating speed (m / min) D: Elastic roll diameter (m) From the above formulas (2) and (6) Substituting equations (4) and (5) into the above equation (II) Next, the setting of the rigidity of the main frames 9, 9 in the CD direction will be described.

Natural frequency (resonance point) in the CD direction of mainframe 9,9
Is the margin α for the source frequency f ₁ when (f _n ) _CD Set.

Then f ₂ = 2f ₁ The second moment of area I _CD in the CD direction is CD deflection δ _CD The natural frequency of the CD direction of the frame (f _{n) CD} is From equations (9), (11) and (12) As described above, the relationship between the maximum operation speed and the minimum operation speed in the operation speed range L is set so that the minimum operation speed is 1/2 of the maximum operation speed, and the main frame 9,9 has a specific MD direction. The second moment of area I _MD in the MD direction is determined so that the frequency (f _n ) _MD becomes α (a margin) times the excitation frequency f _{2 at} the maximum operating speed, and the main frames 9, 9 the natural frequency of the CD direction by (f _{n) CD} determines the minimum operating speed of the excitation source frequency f ₁ of 1 / alpha in the CD direction so that the multiple second moment I _CD of time, the main Vibrations due to the natural frequencies of the frames 9, 9 in the MD and CD directions do not fall within the operating speed range L, thereby enabling stable calendar work with less vibration.

Set the natural frequency in the MD and CD directions as described above,
Upon determining the second moment so that its natural frequency, the main frame 9, 9 length h ₁ is much larger plate-shaped with respect to the thickness method b ₁ as shown in FIG. 1 With this configuration, manufacturing becomes easy, the weight can be reduced, and the occupied space can be reduced.

The super calendar device of the present invention is not limited to the above-described embodiment, but may be variously modified without departing from the gist of the present invention.

[Effects of the Invention] As described above, according to the super calendar device of the present invention, it is possible to prevent the vibration of the main frame within the operating speed range of the super calendar device and perform a good calendar operation, and Since there is no need to increase the rigidity of the main frame more than necessary, various excellent effects such as reduction in the weight of the main frame and reduction of the occupied space can be achieved.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention, and FIG.
FIG. 3 is a perspective view of a main frame shown in FIG. 3, FIG. 3 is a diagram showing a relationship between a main frame vibration amplitude and a natural frequency in the present invention, FIG. 4 is a side view of a super calendar device, and FIG. 5 is a conventional super calendar. FIG. 6 is a plan view of the apparatus, and FIG. 6 is a diagram showing the relationship between the main frame vibration amplitude and the natural frequency in the conventional super calendar apparatus. 1 is a metal roll, 2, 2 'is an elastic roll, 3 is a product, 5 is a tie beam, 6 is a bearing, 7 is an upper frame, 8 is a roll storage post, 9 is a main frame, Vmax is a maximum operating speed, and L is an operation. Speed range, f ₁ and f ₂ are the source frequency, (f
_n ) _MD , (f _n ) _CD is the natural frequency, I _MD , I _CD are the second moment of area, h ₁ is the length dimension in the front-rear direction, and b ₁ is the thickness dimension in the width direction.

Claims (1)

(57) [Claims] A super calender having a structure in which left and right main frames are connected by tie beams extending in a width direction, an operating speed range is set, and a vibration source at the maximum operating speed in the operating speed range of the super calender is provided. The length in the front-rear direction of the main frame is determined so as to have a second moment of area having a natural frequency higher than the frequency, and is smaller than the vibration source frequency at the minimum operation speed in the operation speed range of the super calendar device. A super calender device wherein the thickness in the width direction of the main frame is determined so as to have a second moment of area having a natural frequency.