JPH0334295Y2 - - Google Patents

Description

[Detailed description of the invention] Conventionally, in a blade coater, the paper 1 runs along a backing roll 2 as shown in FIG. 4 onto paper 1. The coating liquid 4 transferred onto the paper 1 is controlled by a blade 5 to adjust the film thickness and improve smoothness. A tube 6 is provided on the back of the blade, and a poppet valve 7 is connected to the tube 6 and keeps its position unchanged as pressure increases or decreases on the blade 5. A stem 8 is provided which is pressed into contact with the stem 8. When pressure is applied to the blade 5 by the coating liquid, a pressing force is applied to the tube 6 and the stem 8 is pressed, so that the valve seat 9 of the poppet valve 7 opens. When the valve seat 9 is opened in this way, pressurized air flows into the tube 6 through the valve seat, and a force corresponding to the reaction force of the blade 5 acts on the blade 5 through the tube 6. The film thickness is adjusted using the blade 5.

However, the poppet valve 7 shown in FIG. 1 has the disadvantage that the valve seat 9 is worn out due to the small amount of air adjustment, and the position of the blade 5 is detected by the stem 8, which is connected to the valve seat 9. , pressure balance control was difficult. Further, it was difficult to set the blade zero adjustment (the state in which the tip of the blade lightly touches the surface of the bucking roll, that is, the state in which the blade linear pressure is zero).

This invention was proposed to solve the above-mentioned conventional drawbacks.A displacement sensor is attached to the rear of the stem, thereby making the movement of the stem clear and ensuring zero adjustment. The poppet valve has a blade that runs along the surface of the paper and comes into contact with the surface of the paper coated with the coating liquid, and the tip of the poppet valve stem is pressed against the blade side of the inner surface of a tube that is installed on the back of the blade and whose internal pressure can be adjusted. In such a blade linear pressure control device, a displacement type sensor is attached to the rear of the stem, and a servo mechanism is provided which is activated by the displacement of the displacement type sensor, and the servo mechanism is installed on the passage for sending air pressure to the tube. It is an object of the present invention to provide a blade linear pressure control mechanism configured to control a control valve.

An embodiment of the present invention will be explained below with reference to the drawings. FIG. 2 shows an embodiment of the present invention, and the same parts as in FIG. 1 are denoted by the same reference numerals. The tip of the blade 5 is in contact with the surface of the paper 1 so that the coating liquid applied to the paper 1 can be adjusted in film thickness and smoothed by the blade 5.

A tube 6 is in contact with the back surface of the blade 5, and a poppet valve 10 having a stem 8 whose tip presses against the blade 5 side of the inner surface of the tube 6 whose internal pressure can be adjusted is used to pressurize the blade 5. It is provided so that its position remains unchanged despite increases and decreases.

There is no valve seat in the poppet valve 10 as shown in the poppet valve 7 of FIG. 1, but instead a displacement sensor 11 is attached to the rear of the stem 8.
In the figure, 12 is a control valve, 13 is a displacement meter unit, 14 is a servo amplifier, 15 is a servo mechanism, 16 is a regulator, and 17 is a displacement setting value.

Now, in FIG. 2, when the pressure applied by the coating liquid is applied to the blade 5, the pressure is applied to the tube 6 and presses the stem 8, so that the displacement sensor 11 at the rear of the stem 8 detects that the stem 8 is pressed. The output from the displacement sensor 11 is
It is guided to a servo mechanism 15 via a displacement meter unit 13 which is a control system, and further via a servo amplifier 14.
The output from the servomechanism 15 is electro-pneumatically converted to adjust the control valve 12, and is partially fed back to the regulator 16. In addition, a separate pressure regulating valve is provided for source pressure control, and control valve 1
2 is designed to supply air pressure at a constant pressure. Therefore, due to the operation of the displacement sensor 11,
The control valve 12 opens via the servo mechanism 15, air pressure is supplied into the tube 6, and the tube 6 applies a force equivalent to the reaction force of the blade 5 to the blade 5, causing the blade 5 to reduce the coating film thickness. Control takes place.

As described above, in the present invention, a displacement sensor is provided in place of the valve seat in the conventional poppet valve, making it possible to perform minute pressure adjustment in relation to the amount of displacement and the pressure regulating valve. There are no problems such as damage to the seat or clogging.

In addition, the pressure inside the tube and the poppet valve body are equal, eliminating the influence of pressure differences, and by installing a displacement sensor at the rear of the stem.
The stem is displaced by the pressure applied to the tube of the coating liquid, and the displacement sensor is activated, making it easy to control the air pressure flowing into the tube via the servo mechanism and control valve. Setting the zero adjustment becomes easy, and the tube setting position can be freely selected depending on the thickness of the paper.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a conventional example of a blade bucking tube type pressure control device, and FIG. 2 is a side sectional view of a blade linear pressure control mechanism showing an embodiment of the present invention. Explanation of the main parts of the diagram, 1... paper, 2... bucking roll, 5... blade, 6... tube,
8... Stem, 10... Poppet valve, 11... Displacement sensor.

Claims (1)

[Scope of utility model registration request] It is equipped with a blade 5 that runs along the bucking roll 2 and comes into contact with one side of the paper coated with the coating liquid, and is provided on the back of the blade 5, on the blade 5 side of the inner surface of a tube 6 whose internal pressure can be adjusted. poppet valve 1
In this blade linear pressure control device, a displacement sensor 11 is attached to the rear of the stem 8, and a servo mechanism is provided which is activated by the displacement of the displacement sensor 11. A blade linear pressure control device, characterized in that it controls a control valve 12 provided on a passage that feeds the water into the tube 6.