JP2523160B2 - Trim separation cyclone control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to finishing equipment in a papermaking process, for example, a winder and a cutter, which winds a trim generated from both sides of a raw paper when the raw paper is cut to obtain a product. The present invention relates to a control method for a centrifugal cyclone that separates trim and air after sending.

[Prior Art] Generally, when separating solids in a fluid, a centrifugal cyclone utilizing the difference in specific gravity is often used.
The finishing equipment at the end of the papermaking process has a winder and a cutter. In the above equipment, when a product of a required size is taken from the base paper, trim occurs from both sides. This trim is usually shredded by a shredder fan with a cutter blade, blown to the outside of the finishing room, accumulated, and reused as a papermaking raw material. The air and trim must be separated immediately after being blown into the trim processing chamber, and a centrifugal cyclone is often used as this method. At this time, it is rare that one finishing equipment, for example, a winder or a cutter, corresponds to one cyclone, and usually one trim separation cyclone processes the trim of a plurality of finishing equipments. Is.

FIG. 2 is a schematic view of a normally used trim separation cyclone. Explaining the trim separation treatment method, an air supply port 2 including a trim from the side of the cyclone 1 is provided on the tangent line of the cyclone 1. The cyclone 1 is provided with a trim discharge port 3 in the lower part, an air discharge port 4 for separated air in the upper part, and 2 is provided between the air discharge port 4 and the exhaust fan 5.
A secondary air suction port 9 is provided. Each finishing equipment winder A, B, cutter C, D is provided with a shredder fan 7, and each shredder fan 7 is connected to the supply port 2 by a trim air duct 8.

The trim generated from each finishing equipment A, B, C, D is sucked by the shredder fan 7, shredded by the cutter blade provided inside the shredder fan, and blown to the supply port 2 through the trim air duct 8 to be cyclone. In 1 the centrifugal force separates the trim from the air.

The separated trim is discharged from the trim discharge port 3, and the air is sucked by the exhaust fan 5 and discharged into the atmosphere.

However, winders A, B, cutters C, D
Are intermittent motions such as rolls of base paper rolls, unloading of products, etc., and the stop time is not constant among the facilities, and at this time, the shredder fan 7 is also stopped and the air volume entering the cyclone 1 is The flow in the cyclone 1 is reduced and the flow in the cyclone 1 is disturbed, and the amount of air discharged to the outside of the cyclone is also reduced.

If the air volume of the exhaust fan 5 is constant, it is necessary to adjust this decrease somewhere. Therefore, the secondary air suction port 9 for blowing the secondary air provided in front of the air discharge port 4 of the finishing equipment is used. Adjust the air volume by sucking the shortage of air volume due to the stop.

Another example (not shown) is one in which the exhaust fan 5 is directly connected to the air outlet 4.

[Problems to be Solved by the Invention] As described above, when trimming processing is performed from a plurality of finishing equipment, for example, a winder, a cutter, etc., to one cyclone, the following changes occur due to fluctuations in the air volume involved in its operation and stoppage. Issues arise.

When there is no secondary air blow, the suction force of the cyclone exhaust fan wins and the inside of the cyclone becomes a negative pressure temporarily, the air flow inside the cyclone is disturbed and the trim separation capability decreases, and the trim flows to the exhaust fan side. Also comes out.

When the secondary air blowing section is provided, the air in the cyclone processing chamber is intermittently absorbed, and the indoor environment is not stable.

Also, when the operation of the finishing machine is restarted and the air volume rises, there is a case where the secondary air is blown out from the secondary air blowing portion instantaneously.

Furthermore, the cyclone exhaust fan is a total value that adds the shredder fan air volume of each finishing equipment, and continues to discharge useless air even when each finishing equipment is stopped, resulting in large energy loss etc. have.

An object of the present invention is to solve the problems that cannot be solved by the conventional techniques as described above, and to provide a trim separation method for providing equipment with stable trim separation performance and energy saving.

[Means for Solving the Problem] The present invention provides a trim separation cyclone for processing trim blown from one or more finishing equipments with a micro pressure gauge, and a signal from the micro pressure gauge controls the internal pressure of the trim separation cyclone. This is a control method for the trim separation cyclone, which is characterized by adjusting the exhaust air volume of the exhaust fan so that the set pressure value is achieved. The trimming from multiple finishing equipment (winder cutter) is processed for one cyclone. At this time, the air volume that flows into the cyclone fluctuates due to the intermittent operation of the winder and cutter.Therefore, the exhaust fan has an exhaust volume corresponding to this fluctuating air volume to maintain the pressure inside the cyclone constant and stabilize the cyclone separation performance. In addition, it is a control method for a trim separation cyclone that reduces unnecessary energy loss by adjusting the displacement to the required amount. You.

[Embodiment] An embodiment of a method for controlling a trim separation cyclone according to the present invention will be described below together with its apparatus.

 FIG. 1 shows an apparatus for carrying out the present invention.

Reference numeral 1 in the drawing denotes a cyclone, which has a supply port 2 on the side, a trim discharge port 3 on the lower part, and an air discharge port 4 on the upper part, and the air discharge port 4 controls the rotation speed. It is connected to the exhaust fan 5 with an inverter. The exhaust fan 5 has an exhaust capacity capable of being in time during all operations of the finishing equipment connected to the cyclone 1. Each of the winders A and B and the cutters C and D is provided with a shredder fan 7, and each shredder fan 7 and the supply port 2 are provided.
The space between them is connected by a trim air duct 8.

The side wall of the cyclone 1 is provided with a micromanometer 6 for measuring the pressure inside the cyclone. The micromanometer 6 is electrically connected to the exhaust fan 5, and the pressure change signal of the micromanometer 6 is sent to the inverter of the exhaust fan 5. The amount of exhaust air is adjusted by inputting and increasing or decreasing the number of revolutions of the exhaust fan 5.

 Next, the actual operation will be described.

Trims generated from finishing equipment A, B, C, D such as winders and cutters are sucked by each shredder fan 7, shredded by a cutter blade provided inside the shredder fan, and supplied via a trim air duct 8 It is blown into the cyclone 1 through the mouth 2. The blown trim is separated from the air in the cyclone by centrifugal force, discharged from the trim discharge port 3, accumulated, and reused as a papermaking raw material.

The separated air is sucked into the atmosphere by the exhaust fan 5 connected to the air outlet 4.

Here, if any of the finishing equipment A, B, C, D is stopped, the amount of inflowing air supplied to the cyclone 1 is reduced accordingly, the pressure inside the cyclone decreases, and the micromanometer 6 detects this pressure decrease. . The pressure drop signal of the micro pressure gauge 6 is input to the inverter of the exhaust fan 5 and is automatically adjusted by the inverter so as to reduce the rotation speed of the exhaust fan 5 and maintain the set pressure inside the cyclone 1. When the finishing equipment is stopped and the pressure in the cyclone 1 becomes high, the rotation speed of the exhaust fan 5 is increased by the signal of the micro pressure gauge 6 to maintain the pressure inside the cyclone 1 at the set pressure. , Is automatically controlled so that the internal pressure of the cyclone 1 is always constant.

[Advantages of the Invention] According to the present invention, a micro pressure gauge is attached to a cyclone to constantly check the pressure inside the cyclone when a part of a plurality of finishing equipment is stopped, and to control the exhaust air volume of an exhaust fan. Therefore, the internal pressure of the cyclone is always constant, the internal flow is stable, and the trim separation performance is improved. Also, the exhaust fan is operated at the required number of rotations and there is no energy loss. Further, no air flows in or out of the trim processing chamber, which improves the indoor environment.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of an apparatus for carrying out the method of the present invention. FIG. 2 is a schematic diagram of a conventional trim separation cyclone. 1 ... Cyclone, 2 ... Supply port 3 ... Trim discharge port, 4 ... Air discharge port 5 ... Exhaust fan, 6 ... Micro pressure gauge 9 ... Secondary air suction port A, B ... Winder C, D …… Cutter 7 …… Shredder fan 8 …… Trim air duct

Claims (1)

(57) [Claims] 1. A micro pressure gauge is provided in a trim separation cyclone that processes trim blown from one or more finishing equipment, and a signal is output from the micro pressure gauge so that the internal pressure of the trim separation cyclone becomes a set pressure value. A control method for a trim separation cyclone, which is characterized by adjusting an exhaust air volume of a fan.