JPS5844428B2 - Equipment for painting strips - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for coating strips, in particular paper or cardboard, in which the rolling doctor bed surrounding the rolling doctor roll over an angle greater than 180° has an elastomeric abrasion resistant coating. (% Kaimei 46
-1388 Publication).

Making the rolling doctor bed from an elastomeric material increases the elasticity of the rolling doctor bed and results in an extremely homogeneous coating.

In this case, the rolling doctor bed is fixed to a leaf spring,
Particularly good results are obtained if it is pressed against a counterroll.

This leaf spring must be made of spring steel as thin as possible in order to obtain a high elasticity that allows for the possible oscillations of the rolling doctor bed.

However, this requirement requires that the leaf springs bear the load in order to guarantee reliable clamping, guidance and sufficient stability over the length of the coating device, which in modern machines can exceed 5 m. This is contrary to the practical requirements of the required thickness.

A further problem with such an arrangement lies in the connection between the elastomer and the leaf spring.

Mere gluing of elastomeric materials is therefore generally not sufficient, and the rolling doctor bed may separate from the spring steel.

Connecting the rolling doctor bed with leaf springs and screws is
Vulcanizing the rolling doctor bed directly onto the leaf spring or embedding the leaf spring in the rolling doctor bed also requires additional costs.

Known rolling doctors, for example the rolling doctor according to DE 2008 082 A1, are distributed over their entire length behind the rolling doctor bed and typically have five
It has adjusting members at intervals of crn~10 cm, by means of which the rolling doctor roll can be precisely adjusted relative to the paper.

Therefore, for example, when using a rolling doctor roll for a sheet of paper with a width of 5 m, 50 to 100 adjustment members are required.

Furthermore, when starting up the coating device, all these adjusting elements must be adjusted individually, fixed and, if necessary, due to the different thicknesses of the paper in different ranges of paper width. It is necessary to adjust the

Since this adjustment work can only be carried out within the machine and usually has to be carried out while the machine is in operation, a considerable amount of space is required to provide access to the adjustment device.

The object of the invention is to improve a device of the type mentioned at the outset.

According to the invention, this problem is solved by an apparatus for coating strips, which has a rolling doctor roll and a rolling doctor bed, the doctor bed surrounding the rolling doctor roll over an angle greater than 180° being elastic and wear-resistant. The rolling doctor bed and the apron for elastically fixing the rolling doctor bed are a single component made of rubber-elastic material, and the rolling doctor bed is made of rubber-elastic material over its entire length. The solution is that the entire system is guided by a one-piece holder, which has grooves in the area of the rolling doctor roll that receive the pressure-compensating material.

Because the rolling doctor bed is guided along its entire length by a one-piece holder, this torsion-resistant holder only needs to be adjusted or adjusted on both sides of the coating device, and the interior of the device over the entire width of the device can be adjusted. This eliminates the need for troublesome adjustments.

This results in a compact construction of the device, by saving the space that would otherwise be required for the operator to access the adjustment device inside the device, which in turn reduces the space requirements of the device.

Furthermore, the presence of pressure-compensating elements in grooves in the holder behind the rolling doctor bed in the area of the rolling doctor roll prevents vibrations of the rolling doctor roll caused by variations in paper thickness or other non-uniformities. Buffered.

As a member for damping vibrations, a plastic foam can be arranged in the groove of the holding body.

However, according to a preferred embodiment of the invention, a pressure-loaded hose is arranged as the pressure-compensating element.

In order to achieve a particularly good elastic effect in this embodiment, it is advantageous for the diameter of the hose to be at least twice the diameter of the rolling doctor roll, since the hose already has a good damping effect due to its own elasticity. Advantageously, it is loaded with compressed air at 0.05 to 0.8 atmospheres.

This hose pushes the rolling doctor bed evenly, and the rolling doctor bed and rolling doctor roll are able to move the paper without the need for new adjustments, based on the relatively even distribution of pressure behind the rolling doctor roll. It follows thickness fluctuations in the process and enables coating with uniform thickness.

Furthermore, within certain limits, it is also possible to adjust the coating thickness using compressed air.

According to a preferred embodiment of the invention, the holding body is formed by an extruded profile with a sickle-shaped cross section.

Generally, the holder of the present invention can be manufactured by cutting the internal material, but extrusion has significant advantages over cutting.

This means that, once obtained, a shaped body with an advantageous cross-sectional shape can be produced in any length using the same extrusion head and then adapted to any machine width without difficulty and without material loss. It is possible to produce molded bodies with the same length and cross section.

Moreover, extrusion processing can be carried out at a lower cost and significantly faster than machining solid material.

This requires the production of considerable lengths of shaped bodies with complex cross-sectional shapes that can only be machined on special lathes.

Aluminum and its alloys are suitable materials for making the holder.

Aluminum is significantly lighter than other metals, so even a 5 m long holder can be transported and installed by one worker without any difficulty.

This is not possible if the holder consists of other materials.

Furthermore, aluminum has the advantage of being less susceptible to corrosive effects, such as those that occur when using paints, and is particularly suitable for extrusion.

It is also significant that the cross section of the holder is sickle-shaped.

In this case, the part of the sickle-shaped handle serves to tighten the holder into the clamping device which simultaneously receives the apron of the rolling doctor bed, and the clamping to the rolling doctor bed serves to connect it by force, and the part of the sickle-shaped blade to apply the pressure. Serves for receiving the compensating element.

In order to prevent the apron from being pulled out of the tightening device when starting up the painting equipment, which generates strong forces, the tightening jaws that come into contact with the apron are provided with grooves, and within these grooves there are raised ridges provided at corresponding locations on the apron. Advantageously, the parts are engaged.

The arrangement of the groove and the ridge ensures that the rolling doctor roll is always located in the same position relative to the clamping jaws.

In other words, the groove and the raised portion that prevent the apron from bowing out also allow the rolling doctor bed to be adjusted at the same time.

If the rolling doctor roll is normally driven in the direction opposite to the direction of paper movement, when starting the coating device, the rolling doctor bed is made of rubber-elastic material, e.g. Vulko.
When made of a polyurethane elastomer sold under the trade name llan, there is a tendency for the rolling doctor roll to run away towards the counterroll while it is not yet in contact with the paper or the counterroll.

The resulting rocking movement of the rolling doctor bed is limited in a preferred embodiment of the invention by front and rear stop surfaces on the holder.

These stop surfaces extend over the entire length of the holder in the form of limiting grooves.

In this case, the roller blade section of the clamping jaw which is located on the side opposite to the extension of the apron engages in this limiting groove as a stop.

The invention will now be explained with reference to the drawings: The rolling doctor bed 1 is integrally formed with the apron 2 and is manufactured by extruding a polyurethane-distomer melt using an extruder.

In this case, the melt is a combination of ethylene glycol adipate polyester and naphthalene-1,5-diisocyanate.

In this case, polyhydric alcohols are used as reticulating agents.

This melt, when solidified, forms an expensive elastomeric plastic known under the trade name Vulkollan.

The molded product obtained by extrusion molding has a rolling doctor base 1 and an apron 2 integrally.

The apron 2 is designed as a lateral extension of the rolling doctor bed 1 on the side opposite the rolling doctor roll 4.

The apron 2 comprises a bulge 3 located within the clamping jaw 5 and held by the clamping jaw 6.

The rolling doctor roll 4 is surrounded by the rolling doctor bed 1 over an angle greater than 180°.

This rolling doctor blade 1 is formed by cleaning grooves 7 and 8.
It is divided into two supporting surfaces.

The sum of these three supporting surfaces is approximately 1/3 of the cylindrical surface of the rolling doctor roll 4.

Water is passed through the cleaning grooves 7 and 8 by supply conduits, not shown, so that the paint particles that have entered are removed from the rolling doctor roll 4 and are prevented from sticking to the lip-shaped part of the rolling doctor bed 1. Prevented.

A holder 9 is arranged behind the rolling doctor bed 1 to guide it, and a pressure hose 10 is arranged in a groove 18 provided in this holder 9 at a location corresponding to the rolling doctor roll 4. .

The pressure hose 10 rests directly on the back side of the rolling doctor bed 1 and presses the rolling doctor roll 4 against the paper 12 after the holder 9 has been adjusted towards the counterroll 11 .

The counterroll 11 is constructed as a roll with two layers of rubber blanket.

In this case, the inner layer 13 has a lower Shore hardness than the outer layer 14.

The oscillating movement of the rolling doctor bed 1 is limited by a stop 15 formed by a section extending in the opposite direction to the clamping jaws 5, 6, cooperating with a stop surface 16 and a stop surface 17 of the holder 9. .

[Brief explanation of the drawing]

The drawing shows one embodiment of the present invention, and is a cross-sectional view of the coating apparatus of the present invention. 1... Rolling doctor bed, 2... Apron, 3... Raised portion, 4... Rolling doctor roll, 5゜6... Tightening. Joe, 7,8
...Cleaning groove, 9...Holding body, 10...
...Pressure hose, 11 ...Counter roll, 1
2... Paper, 13, 14... Layer, 15.
... Stopper 16, 17 ... Stop collar surface, 18 ... Groove.

Claims (1)

[Claims] 1. An apparatus for coating a strip material having a rolling doctor roll and a rolling doctor bed, the rolling doctor bed surrounding the rolling doctor roll over an angle greater than 1800 mm being made of a rubber-elastic wear-resistant material. ,
The rolling doctor bed 1 and the apron 2 for elastically fixing the rolling doctor bed 1 are a single component made of a rubber-elastic material, and the rolling doctor bed 1
is guided over its entire length by an integral holder 9, which holder 9 has a groove 18 for receiving a pressure-compensating element in the area of the rolling doctor roll 4, Equipment for painting strips.