JP2910012B2 - Head box for paper machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a head box for a paper machine.

[0002]

2. Description of the Related Art In a paper machine head box, a pulp raw material is uniformly distributed in a width direction of a paper machine by a raw material distribution device, and the raw material is diffused. is there.

In the prior art, in order to supplement the distribution and diffusion of pulp raw material by the raw material distribution device, a stationary (non-rotating) fixed or rotationally driven perforated roll is arranged between the raw material distribution device and the slice. A diamond-shaped current suppressing element is arranged in a slice (Japanese Patent Application Laid-Open No. 58-23983).

[0004]

However, the prior art has the following problems. The perforated roll allows the stock to flow from the front to the back with respect to the flow, and it cannot be expected to generate turbulence due to the generation of vortices on the back side. In addition, a perforated roll is formed by alternately and repeatedly forming a portion having a hole and a portion having no hole in the roll axis direction, and the flow state is different between the portion having a hole and the portion having no hole. Impairs uniform distribution of stock.

[0005] The rhombus-shaped flow restricting element forms a streamline with respect to the flow of the stock, and it is not expected that turbulence is generated around the element due to the generation of vortices. SUMMARY OF THE INVENTION It is an object of the present invention to generate an appropriate turbulence in a stock in a paper machine head box, improve uniform distribution of stock fibers, and improve formation.

[0006]

According to the first aspect of the present invention, a stock is sent out from the opening of the slice in a uniform flow.
For a paper machine equipped with a stock diffusion bar having a circular cross section and no surface holes, intersecting the stock flow direction in the slice.
In the head box, the stock diffusion bar is used as a splice yarn.
They are connected so as to be floatingly supported in the flow of the stock .

[0007]

According to the first aspect of the present invention, the following operations are provided. Since the stock diffusion bar has a circular cross section like a solid round bar or a hollow round bar and intersects with the stock flow direction, a large vortex is generated on the back side of the stock flow with respect to the stock flow. Appropriate turbulence can be generated in the stock due to the eddy current effect. The turbulence occurrence bar is
The bar is a bar without surface holes, and the flow state in the bar axis direction becomes uniform, so that the stock can be evenly distributed in the machine width direction.

Proper turbulence can be generated in the stock by connecting the stock diffusion bar to the splice and floating support in the stream.

[0010]

FIG. 1 is a schematic diagram showing a first embodiment,
2 is a schematic diagram showing a second embodiment, FIG. 3 is a schematic diagram showing a third embodiment, FIG. 4 is a schematic diagram showing a fourth embodiment, and FIG.
FIG. 6 is a schematic diagram showing an embodiment, and FIG. 6 is a schematic diagram showing a sixth embodiment.

(First Embodiment) (FIG. 1) A head box 10 is constructed as shown in FIG. 1, and a pulp raw material passes through a taper header 11, a manifold step 12 (raw material distribution device), a slice 13, and a slice lip. At 14, it is drained onto the forming wire from a slice outlet 15 whose opening is adjustable.

Here, the head box 10 has first to first positions at three positions in the slice 13 along the stock flow direction.
A third stock diffusion bar 16, 17, 18 is provided. Each bar 16-18 has a circular cross section and no surface holes,
It is arranged orthogonally to the stock flow direction in the slice 13.

The first stock diffusion bar 16 is fixedly supported by bolts 19 on the side plate 10A of the head box 10. Then, the second and third stock diffusion bars 17, 18
Is connected to the first stock diffusion bar 16 by a splice yarn 20. The bars 17, 18 are supported so as to be close to the specific gravity of the stock and to be free to float in the stock flow, in other words, to be able to vibrate.

The diameter of the stock diffusion bars 16, 17, 18 is gradually reduced as the slice 13 gradually decreases its channel height in the stock flow direction. And the small diameter bar 17 and the smaller diameter bar 18
Are connected to the splice yarn 20 at a plurality of positions in the axial direction, so that bending deformation due to flow force can be prevented.

The operation of this embodiment will be described below. Since the stock diffusion bars 16, 17, and 18 have a circular cross section and intersect with the stock flow direction, a large vortex is generated on the back side of the stock flow with respect to the stock flow. An appropriate turbulence can be generated. The stock diffusion bars 16, 17, and 18 are bars without surface holes, and the flow state in the bar axis direction becomes uniform, so that the stock can be uniformly distributed in the apparatus width direction.

By connecting the stock diffusion bars 17 and 18 to the splice 20 and floatingly supporting them in the flow,
The bars 17, 18 can be vibrated in the flow. By this vibration action (vibration effect), appropriate turbulence can be generated in the stock.

By providing a clearance between a bolt 19 for supporting the first stock diffusion bar 16 on the side plate 10A of the head box 10 and a bolt hole of the side plate 10A through which the bolt 19 is inserted, paper is provided. The material diffusion bar 16 may be freely movable, and as a result, the bar 16 may be supported so as to be able to vibrate in the material flow.

(Second Embodiment) (FIG. 2) The second embodiment is different from the first embodiment in that the first stock diffusion bar 16 is also connected to the end face of the manifold step 12 by a splicing thread 20, It has been supported so that it can vibrate in the stock flow.

(Third Embodiment) (FIG. 3) The third embodiment differs from the first embodiment in that only a first stock diffusion bar 16 fixed and supported during stock flow is provided. .

(Fourth Embodiment) (FIG. 4) The fourth embodiment is different from the second embodiment in that only the first stock diffusion bar 16 supported so as to be able to vibrate during stock flow is provided. That is.

(Fifth Embodiment) (FIG. 5) The headbox 40 of the fifth embodiment is configured as shown in FIG.
After passing through the (material distribution device) and the slice 42, the slice lip 43 allows the slice to flow out from the slice outlet 44 whose opening is adjustable onto the forming wire.

Here, the head box 40 is provided in the diffusion chamber 42A in the L-shaped slice 42 in the stock diffusion bar 4A.
5 are provided. The stock diffusion bar 45 may be fixedly supported during the stock flow, or may be supported so that it can vibrate during the stock flow.

(Sixth Embodiment) (FIG. 6) The sixth embodiment is substantially different from the fifth embodiment in that the shape of the diffusion chamber 42A of the slice 42 is different, and the inside of the diffusion chamber 42A is larger. That is, a stock diffusion bar 46 having a diameter is provided.

In the practice of the present invention, a vibration generator (30 in FIG. 1) such as a vibrator is provided on a support for supporting the stock diffusion bar on the side plate of the head box. What vibrates in the stock flow may be used.

[0025]

As described above, according to the present invention, in a head box for a paper machine, appropriate turbulence is generated in the stock, the uniform distribution of the stock fibers is improved, and the formation is improved. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment.

FIG. 2 is a schematic diagram showing a second embodiment.

FIG. 3 is a schematic view showing a third embodiment.

FIG. 4 is a schematic view showing a fourth embodiment.

FIG. 5 is a schematic view showing a fifth embodiment.

FIG. 6 is a schematic view showing a sixth embodiment.

[Explanation of symbols]

 10, 40 Head box 13, 42 Slice 16, 17, 18, 45, 46 Stock diffusion bar 20 Splice yarn 30 Vibration generator

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 42-12296 (JP, B1) JP 40-568 (JP, B1) (58) Fields surveyed (Int. Cl. ⁶ , DB name) D21F 1/02 D21F 1/18

Claims (1)

(57) [Claims] 1. A paper machine comprising a stock diffusion bar having a circular cross section and having no surface holes, which intersects with the flow direction of stock in a slice when feeding stock in a uniform flow from an opening of a slice. In the headbox, the stock diffusion bar is connected to a splice yarn to allow
A head box for a paper machine characterized by being supported by printing .