JPS5922151Y2 - Heat treatment equipment - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a heat treatment device for nonwoven fabric.

Non-woven fabrics are fabrics made by directly bonding fibers, etc., and can use any type of fiber, can provide a wide range of properties, are simple and inexpensive, and have great flexibility in operation. In addition, it has many advantages in use, such as being light, highly elastic, having good dimensional stability, high resilience, and being resistant to wrinkles.

Furthermore, it has been pointed out that it has great breathability, so you won't get stuffy, and it has high heat retention properties.

Nonwoven fabrics are used for filters, insulation materials, backing materials,
We have an extremely wide range of products including shoe fabrics, shoulder pads, soles, linings, ties, tablecloths, curtains, wallpaper, sheets, and bed pads.

In addition to cotton, the raw material fibers may be arbitrary, such as rayon, acetate, polyester, nylon, vinylon, and acrylic.

In the manufacturing process, an adhesive is added to the raw material web, heat bonded, dried, and polished to produce a product.

As the adhesive, thermoplastic resin, thermosetting resin, natural rubber, synthetic rubber, thermoplastic fiber, etc. are used.

When the adhesive-containing web is heated under pressure, the adhesive melts and bonds the fibers together.

Conventionally, heat treatment equipment consists of one or two pairs of heat treatment devices.
Many used press rolls.

In this system, a set of two press rolls are provided vertically and parallel to each other at a constant interval, and the wave is pressurized and heated while passing through the rolls.

Since the web is sandwiched between two rolls and passes along a common tangent between the two rolls, the time of contact with the rolls is extremely short.

Since the heat treatment time is short, high pressure or high temperature must be applied.

Moreover, unless the web is thin, it will not be possible to uniformly heat the inside.

In fact, conventional heat press rolls were only effective for thin webs of 10-40 g/m2.

Even if the temperature is raised, it must not exceed the appropriate temperature range of the adhesive, and there is a natural limit.

If the pressure is increased, only a paper-like surface with a smooth surface will be produced.

Nonwoven fabrics with shiny surfaces have drawbacks in terms of bulkiness and breathability.

When the flat member is brought into contact with the roller, the contact area is extremely narrow.

In fact, if both the roller and the planar member are rigid bodies, the contact area S1 between them is O.

However, since the web is highly flexible, it deforms elastically.

The radius of the roller is R, and the deformation of the web (depth of the dent) is d.
Then, the contact area is given per unit width of the web.

Since d is very small, the contact area is extremely small, and therefore the pressure and heat treatment cannot be carried out sufficiently.

When the pressure is increased, d increases and S also increases, but as mentioned above, the surface becomes clogged and it is not possible to obtain a material with good bulk properties.

This invention is based on a completely different idea.

In the present invention, the web is not narrowed by rollers, but is sandwiched between two endless mesh belts, and the web is advanced along the arc of the surface of the drum.

The heating process continues throughout contact with the drum.

Instead of being heated and pressurized only the moment it is sandwiched between rollers,
The heat treatment is performed for most of the time required for one rotation of the drum.

Here, the term "excellent arc" means a curved portion (arc) along the circumference with a central angle of 180 degrees or more.

An arc with a central angle of 180° or less is called an inferior arc.

In other words, if the central angle is α, α is the dominant angle (180° to 3
60°), but the contact area S2 between the web and the drum per drum 1 is:

It can be seen that S2 is superior and larger compared to the prior art Sl.

Moreover, since S2 is proportional to the first power of the drum diameter, the effect increases as the drum diameter increases.

In the prior art SL, the effect of increasing the drum diameter is poor.

It is proportional to the 1/2 power.

Next, an explanation will be given with reference to drawings showing examples.

FIG. 1 is a vertical left side view of a heat treatment apparatus according to an embodiment of the present invention, and FIG. 2 is a vertical front view thereof.

The casing 1 is a vertically long rectangular parallelepiped, and two suction drums 2 and 3 are pivotally supported therein.

The upper suction drum 2 and the lower suction drum are parallel and arranged on the same vertical plane.

Endless mesh belts 4 and 5 are connected to the inside and outside of the casing by suction drums 2 and 3 and guide rollers 6 and 6'.
, 7.7', . . . , 11.11' and so on.

That is, the upper mesh belt 4 starts from the guide roller 6 outside the casing, passes through the inlet 15, goes around the inside guide roller 7, contacts the lower suction drum 3, and moves upward around the upper suction drum 2. spin.

Furthermore, the upper mesh belt 4 reaches the outside from the guide roller 8 via the outlet 16, and then moves upward from the outlet side guide roller 9.

The upper mesh belt 4 is then moved to the upper guide roller 10.
．． 11, and returns to the aforementioned entrance side guide roller 6.

The lower mesh belt 5 also moves in a similar manner.

Inside the casing 1, the upper and lower mesh belts 4 and 5 move in the same manner.

Under the casing, it rotates in the opposite direction.

The lower mesh belt 5 includes an inlet guide roller 6', an inlet 15, a guide roller 7, a lower suction drum 3, an upper suction drum 2, a guide roller 8, an outlet 16, an outlet guide roller 9', a lower guide roller 10', 11'
Proceed endlessly.

Nip rollers 12, 12' provided within the casing press the upper and lower mesh belts 4, 5 with appropriate pressure.

The pressing force of the upper nip roller 12 can be adjusted using a spring.

The anti-meandering device 14.14' is a known device and corrects the meandering of the mesh belts 4, 5.

A hot air circulation device is provided in the axial extension direction of the suction drums 2 and 3.

This is a fan motor 17.17 hot air circulation fan 18.
18' and air heaters 19 and 19'.

It is preferable that the fan motor and hot air circulation fan be installed so that their main axis is on the same straight line as the axis of the suction drum.

Since the hot air circulation fan communicates with the interior of the suction drum, it sucks the air inside the suction drum and forces it into the air heater 19, 19'.

The air heater 19.19' is provided near the ceiling and floor in the circumferential direction of the fan 18.18', has a heater heat exchanger, etc., and heats the air.

Rectifier plates 20 and 20' are attached to the ceiling and floor.

This changes the direction of hot air flowing on the ceiling and floor surfaces and guides it toward the suction drums 2 and 3.

The upper suction drum 2 and the lower suction drum 3 are provided with a large number of through holes 22 and 23 on their circumferential surfaces.

The shaft 21, 21' of the suction drum is integrally connected to the side surface or circumferential surface of the drum via a support plate or the like.

The shaft is rotatably supported by bearings 24 and 28 on the left and right sides.

The interior of the suction drum communicates with the input side of the hot air circulation fan 18, 18', as described above.

The shaft 21, 21' of the suction drum projects to the outside of the cage jig, and sprockets (25, 25') are fixed thereto.

Sprockets 25, 25' are rotated and suctioned by an external drive (not shown).

Rotate the frame.

The operation of the above configuration will be explained.

The web A is fed between the upper and lower mesh belts 4 and 5 from the web feeding section 26 on the entrance side.

While being lightly sandwiched between the upper and lower mesh belts, the wave advances into the casing from the inlet 15 and passes through the guide roller 7.
It then turns downward and advances along the circumference of the lower suction drum 3 by a length corresponding to a certain arc.

The hot air passes through the web from the outside to the inside through the through holes 23.
and enters the inside of the suction drum 3 through the suction drum 3.

Under the action of the hot air, the adhesive in the web begins to melt.

After going around almost the entire circumference of the lower suction drum 3, the web advances diagonally to the upper suction drum 2 while being held between the mesh belts.

In the upper suction drum 2, the hot air passes through the web from the outside to the inside, so that the web continues to be heated.

The web now passes through guide rollers 18 and reaches nip rollers.

Here, it is held between upper and lower nip rollers 12° and 12' and pressurized.

The thickness is determined by the amount of pressure applied.

In other words, the density is determined and the bulkiness can be adjusted accordingly.

Of course, the pressing force of the spring can be adjusted.

The web having a suitable thickness and density exits the casing from the outlet 16 and is discharged from the discharge section 27.

During this time, the adhesive melted by the hot air penetrates between the fibers and hardens.

Next, we will discuss the effects.

Since the suction drum is heated over the entire circumference, even thick webs can be heated evenly.

In fact, according to the present invention, webs with a wide range of thicknesses from 10 to 500 g/m@2 can be heat treated.

The two rollers sandwiching each other is a line contact, but the present invention uses a surface contact.

The web is loosely formed by two mesh belts.
Because they are just sandwiched together, no pressure is applied, and bulkiness and breathability are not lost.

It is possible to produce non-woven fabrics of various types.

Since the web is sandwiched between two mesh belts, even light webs can run at high speeds without scattering.

Since the web immediately after heating is pressed together with a mesh belt by a nip roller whose pressing force can be adjusted, the nonwoven fabric can be finished to a desired density.

That is, the bulkiness of the nonwoven fabric can be adjusted.

By providing the baffle plate, the hot air can be guided to the suction drum reliably and well, so that the web in surface contact with the suction drum can be reliably and well heated.

In the embodiment, two suction drums are provided in parallel, one above the other, but the invention is not limited to this.

In the case of two, it is efficient to pass the belt in a figure-eight pattern like this.

In fact, in this example, the contact angle α (
The dominant angle) is 290°.

Assuming that the radius of the drum is R, the radius of the guide roller 7.8 is b, and the maximum interval between mesh belts is d, the maximum value of the contact angle α can be determined using the drum interval and the position of the guide roller as parameters.

That is, α is It can be found by

Even when there is only one drum, the belt and drum can be brought into contact along a gentle arc using two guide rollers.

In this case, the maximum value of the contact angle α is is given by

Even if the number of drums is 3, 4, or 5, the belt and suction drum can be similarly arranged so as to be in wide contact with each other.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical left side view of a heat treatment apparatus according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view. 1 is a casing, 2 is an upper suction drum, 3 is a lower suction drum, 4 is an upper mesh belt, 5 is a lower mesh belt, 6. 7. 8. 9.10.11 are guide rollers, 6', 7', 8', 9', 10', 1
1' is a guide roller, 12.12' is a nip roller, 1
4.14' is a meandering prevention device, 15 is an inlet, 16 is an outlet,
17.17' is a fan motor, 18.18' is a hot air circulation fan, 19.19' is an air heater, 20.20' is a rectifier plate, 21.21' is a shaft, 22.23 is a through hole, 24, 2
4' is a bearing, 25.25' is a sprocket, 26 is a web feed section, 2F is a web discharge section, 28 is a bearing, and A is a web.

Claims (1)

[Scope of Claim for Utility Model Registration] ■ A casing 1, one or more suction drums 2, 3, etc., which are rotatably installed in the casing 1 and have a large number of through holes on their surfaces, and a suction drum. A rotary drive device, a plurality of guide rollers 6, 6', 7, 7', . two endless mesh belts 4, 5 that move in one direction, a nip roller 12.12' that is provided behind the suction drum and pinches and presses the two mesh belts 4.5, and It consists of a hot air circulation device that circulates hot air, and a baffle plate 20, 20' that is provided in a flow path between the hot air circulation device and the suction drum and guides the hot air to the suction drum, and the two mesh belts 4 and 5 are connected to the casing. Inside the casing, the same movement is maintained while maintaining a narrow interval, and outside the casing, the movement is made around the opposite side.
A heat treatment apparatus characterized in that a web feeding section 26 is provided on the inlet side of the casing, and a discharge section 27 is provided on the exit side of the casing. 2. The hot air circulation device has a fan motor 17.17',
Suction drum 2 driven by a fan motor;
3. The heat treatment apparatus according to claim 2 of the utility model registration, characterized in that it comprises a hot air circulation fan 18, 18' that sucks air from inside 3, and an air heater 19, 19'. 3. The heat treatment apparatus according to claim 1, wherein the suction drums 2, 3, . . . have the same outer diameter and are driven at the same rotational speed. 4. The scope of the claim for utility model registration, in which the number of suction drums is two, and mesh belts 4 and 5 are wound around the two suction drums 2 and 3 arranged in parallel at the top and bottom in a substantially figure-8 shape. The heat treatment apparatus according to item 1.