JPS598553B2 - Method and apparatus for parallel orientation of wood fibers and wafers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a structural wood particle board made into a predetermined shape.
cle board).

This board has one or more layers of wood chips or wood fibers oriented parallel to each other.

This type of product and the advantages of parallel arrangement of wood pieces are shown in U.S. Pat. No. 3,645,].

The method and apparatus of the present invention is an improvement on U.S. Pat. No. 3,478,861 which shows stationary parallel plates arranged in a vertical plane separated from each other by a distance less than the average length of the fibers on the support.

These plates have along their upper edges movable elements, such as stretched strips of string or metal caps, which move along the mutually parallel upper edges in a direction opposite to the immediately adjacent elements.

Vertical plates are stationary and require fibers with tightly controlled shapes.

Single fibers with a width greater than the gap between the two plates, partially broken fibers or too many fibers at one time or in one place will clog the gap and feel the fibers on the movable support below. interrupting the process of weaving or adhering.

This limitation requires careful screening of the fibers and formation of oriented mats of fibers at relatively slow speeds.

Furthermore, if orientation of the fibers perpendicular to the direction of movement of the support is desired, only relatively slow moving supports can be used;
The lower edge of the board must be at a considerable distance from the felt mat, so that some of the fibers become disoriented again.

Other disclosures regarding problems in orienting wood fibers are US Pat.

However, these patents do not disclose or suggest an apparatus or method for orienting fibers in the same direction and as effectively as is done by the practice of the present invention.

The method for producing oriented fiber mats must be capable of processing large amounts of fiber per unit time, which is now standard in the particleboard industry due to the large investment costs of the plant.

For example, a typical 500 ton/day plant requires mat formation at a rate of approximately 360 kg of fiber per minute in 22 hour/day operation.

Generally, in many plants there are four forming heads.

Therefore, four orientation mechanisms are required.

Each orientation mechanism must therefore orient approximately 90 kg of fibers per minute.

And this must be done without interruption or fiber crowding.

Orienting means such as vertical plates or belts must be relatively thin.

If a thin member is used when oriented parallel to the direction of movement of the support, the resulting mat will have ridges, but what is important is that the amount of oriented fibers (hereinafter referred to as output) will increase in the interstitial space. It decreases as the ratio of plate thickness to plate thickness decreases.

This is especially true if the plate-to-plate distance must be small due to short fiber lengths.

A stationary plate with a moving metal cap on the upper edge, such as in US Pat. No. 3,478,861, provides an example where the thickness of the plate is increased at the upper edge by a wider moving cap or groove.

This increased width is taken away from the gap between the plates, thereby reducing the throughput of the device.

The apparatus and method of the present invention operate to orient the wood fibers parallel and perpendicular to the direction of relative movement of the supports.

The present invention also improves the degree of fiber orientation, particularly perpendicular to the direction of movement of the support, so that when the fibers are occasionally bent or partially broken, a large amount of wood can be removed without clogging the gaps between adjacent fiber guide members. It allows the fibers to be oriented continuously in parallel.

Although the invention is directed to the orientation of fibers, ie elements whose length is many times greater than their width, the invention may also be used to orient fibers.

These are the wood elements used today in commercially manufactured wafer plates, such as Aspenite.

The length of the wafer, the dimension in the direction of the fibers, must be slightly longer than its width.

However, if the length to width ratio is very low, for example 2, satisfactory orientation is obtained.

The average length of the fibers must be greater than the distance between adjacent belts, but the width of each fiber is less than this distance.

However, the width of many wafers is greater than the distance between adjacent guide members, thus clogging the space between the stationary fins of the orientation apparatus as shown in US Pat. No. 3,478,861.

The invention allows the wafer to be oriented by movement of the guide members without clogging these spaces, and at the same time allows for high throughput.

The distance from the lower edge of the guide member to the top edge of the moving support or felt-like mat must be greater when orienting wafers than when orienting fibers.

The device has a number of longitudinally straight fiber guide members, each serving as a boundary between adjacent elongated parallel spaces.

In one embodiment, the guide members are spaced relatively rigid plates of tensioned metal, plastic, etc., and in other embodiments, the guide members are endless parallel belts. So, there is.

The guide members are placed equidistant from each other and above the movable support.

The opposed flat surfaces of the guide are in a vertical plane, the longitudinal direction of the guide is in a vertical plane, and the longitudinal direction of the guide is parallel to the movement of the support if the fibers are to be oriented parallel to the direction of movement of the support. or, if it is desired to be oriented perpendicular to the direction of movement of the support, perpendicular to the direction of movement of the support.

The upper edges of the guide members have projecting elements or projections in the same plane as the respective guide member.

Adjacent guide members move parallel to each other but in opposite directions in the direction of their longitudinal axes.

Preferably, this movement is a linear back and forth movement.

This is because this always provides a uniform distance between the lower edge of the guide member and the support or felt-like mat.

The fibers attached from the guide members fall onto and between the guide members.

The fibers extending between the upper edges of two or more movable guide members are rotated in an arc in a substantially horizontal plane and fall onto the movable support between the guide members.

This arcuate movement is assisted by the movement of a projecting element on the upper edge of the guide member.

In the present invention, the fiber guide member is relatively thin and the protruding elements are integral with the guide member so that there is no or little increase in the thickness of the guide member.

This feature provides a very high ratio of interstitial space to fiber guide thickness, thus resulting in high throughput.

This also produces felt-like mats without longitudinal ridges when the fibers are oriented parallel to the direction of movement of the movable support. To provide an improved apparatus and method for parallel orientation of the guide members, the guide members ensuring a relatively high throughput for the movable support below the guide members without clogging of the space between the guide members. It works like this.

Another object of the invention is that adjacent fiber guide members are relatively thin and move in opposite directions in a horizontal plane until the fibers extending between them align and fall into the space between the guide members. The object of the present invention is to provide a device and a method of the type described above, such that the device can be rotated.

Another object is to provide a method and apparatus which makes it possible to orient a wafer of the above-mentioned type, such that it is considerably wider than the width of the fibers, and often wider than or equal to the distance between adjacent guide members.

Embodiments of the present invention will be described in detail below with reference to the drawings.

A first embodiment of the apparatus of the invention for orienting wood fibers is shown in Figures 1, 4, 5 and 5a.

The device includes a plurality of rigid thin parallel plates or strips 12 each arranged in a vertical plane above a movable support 14, such as a caul plate, with each plate 12
has a plurality of upwardly directed projections 16 on its upper edge, which projections are integral with or otherwise connected to the corresponding plate 12.

The lower edges of the boards 12 are spaced above the supports 14 such that the wood fibers fall through the spaces between adjacent boards 12 and fall onto the supports 14 forming a mat 20 of wood fibers 18. It is designed to orient multiple wood fibers in such a way.

As the fibers 18 fall through the space, the plates 12 reciprocate with respect to each other along respective horizontal paths and the supports 14 move in a straight path below the plates.

Each plate 12 moves in one direction and the next adjacent plate moves in the opposite direction.

This is indicated by arrows 22 and 24 (FIG. 1), respectively.

Support 14 is shown in FIG. 1 as movable in the direction of arrow 26.

The lower edge of the plate 12 must therefore be a certain distance (indicated by 25) from the felt mat 20.

This movement is perpendicular to the longitudinal axis of plate 12.

As a result, the wood fibers are oriented perpendicular to the direction of movement of the support 14.

The support 14 is also moved in a direction parallel to the longitudinal axis of the plate 12, as shown in FIGS. 4 and 5, so that the fibers of each mat are approximately perpendicular to the fibers of the next adjacent mat 20. The respective mats 20 can be formed by stacking them on top of each other so that they are oriented in the same direction.

The means for mounting the plate 12 consists of two frames.

All plates are the same: Adjacent plates are held under tension in different frames so that they are in the same plane.

The smaller inner frame moves within the larger outer frame,
The plate attached to the outer frame can thus move freely through the gap in the end member of the inner frame.

Alternatively, both frames may be of the same size so that they can partially move into each other without interfering with each other, as shown in FIGS. 4, 5 and 58.

End members 28 and 30 are part of one frame, and end members 32 and 34 are part of the other frame.

The side members of the frame connecting the respective end members are not shown.

End members 30 and 32 have slots to allow free passage of plates 12 secured to end members 34 and 28.

If the fibers are oriented at right angles to the direction of movement of the support, the plate 12 will be of considerable length, depending on the width of the mat to be felt-like.

For example, when making a mat with a width of 254 cm, the board will have a length V- of about 270 Crrl.

Plates of considerable length are also required if the fibers are oriented parallel to the direction of movement of the support in order to obtain sufficient yields.

Therefore, it is extremely important that the orientation device be lightweight.

Each plate 12 has means 36 shown on end members 28 and 34.
It is pulled under tension.

The tension must be sufficient to maintain plate 12 in a relatively straight position during operation of the device.

The required tension will vary depending on the type of material and the construction of the plate 12.

Preferably, the plate 12 requires only light tension to allow the use of a lightweight reciprocating frame.

Both frames are arranged in the same plane, and a thousand moving stages 44 (5th a)
(Fig.) moves back and forth in a straight path.

In FIG. 5 the frame is in one end position and in FIG. 5a it is in the other end position.

Arrows 38 indicate the distance that each frame is moved from one end position to the other end position, ie the distance that adjacent plates move in parallel in opposite directions during a half cycle.

The sum of the moving distances of both frames, ie, the arrow 38×2, is the entire stroke.

Preferably, only the upper ends of the plates 12 are connected to the end members of their respective frames as shown in FIG.

Preferably, the plate is made of thin sheet metal, but may be made of other materials such as flexible belt material.

If flexibility is used, the plates must be fixed at all their edges to the end members of the respective frame.

If the plates are sheet metal and only their upper ends are connected to the frame, the lower ends of the plates are free and can extend beyond the lowest part of the respective frame.

This extension is indicated by arrow 40 (FIG. 4). This minimizes the distance between the mat 20 of fibers and the lower edge of each plate when the fibers are oriented parallel to the direction of movement of the support 14.

The smaller this distance, the less chance the wood fibers will become misoriented after leaving the space between the respective plates.

Plate 12 and support 1 as shown in Figures 4, 5 and 58.
4 are moved parallel to each other, the mat 20 is moved parallel to the plate 12 without being disturbed by the moving end members 30 and 34.
It may contact or cover the lower edge of the.

4 and 5 show that support 14 is moved in the direction of the longitudinal axis of plate 12, as indicated by arrow 42. FIGS.

This results in a parallel orientation of the fibers 18, as shown by a portion of the felt mat 20.

1 for directing the wood fibers 18 onto a specific area above the board 12.
A pair of parallel side walls 46 (FIG. 4) may be used.

As the board reciprocates, it orients the wood fibers so that they become essentially parallel to the board as they fall onto the support 14 and form the mat 20.

The orienting effect of the reciprocating movement of the plate continues until the wood fibers are completely distributed on the movable plate.

When one end of the fiber contacts the support or felt mat and the other end contacts the fiber guide, the fibers are drawn parallel by the moving guide and deposited onto the support.

The advantage of the reciprocating movement of the plate 12 is a kind of self-cleaning effect due to the sudden stop and reversal of the plate.

This movement is also obtained with endless belts 70 and 100 (Figures 2, 2a and 3).

However, reducing the space between the mat 20 and the lower edge of the belt when the wood fibers are oriented parallel to the direction of movement of the support is generally not possible due to the need to reverse the movement of the belt by means of pulleys. be.

As shown in FIGS. 2 and 3, belt 70 is connected to arrow 82 (
Supports 80 arranged to move in the direction of FIG.
Due to the presence of a plurality of pulleys 74 on both side edges 76 and 78 of the
has.

The struts 72 can also be arranged parallel to, rather than perpendicular to, the direction of movement of the support 80 as shown in FIG.

This requires that the pulley 74 be rotatably supported so that the support 80 can pass underneath the pulley 74.

The tension 72 is placed between a pair of side walls 84 which direct the wood fibers downwardly into the space between the belt tensions 72.

By placing belt 70 on pulley 74, adjacent tensions 72 are moved in opposite directions as shown by arrows 86 and 88.

The belt 70 also has a plurality of protrusions 89 as shown in FIG.
These projections serve the same purpose as projections 16 on plate 12 of FIG.

- The belt 70 also connects to the drive shaft 9 of a drive motor (not shown).
2 and is wrapped around a drive pulley 900 coupled to the drive pulley 900.

Pulley 90 is rotated in the direction of arrow 94 to move belt tension 72 in the direction of arrows 86 and 88.

The belt passes around an idler 96 to tension it and to ensure that the belt tension is always kept in the respective vertical plane.

The embodiments of the invention shown in FIGS.
5 and 5a operate in substantially the same manner as described above with respect to the embodiments of FIGS. 5 and 5a.

For this purpose, the wood fibers fall from a feeding mechanism (not shown) above the tensions 72 of the belt into the space between adjacent tensions 72 and are thereby oriented, so that the fibers are transported to the moving support below. When falling onto 80 it becomes substantially parallel to tension 72.

The protrusions 89 serve to orient the wood fibers extending between adjacent struts 72.

As the wood fibers fall onto support 80, a mat (not shown) of the type shown in FIG. 1 is formed.

A belt modification is shown in Figure 2a, where a plurality of endless belts 100 are used instead of a single belt.

Only one belt is shown in Figure 2a.

Each belt 100 is attached to a side edge 76 of the moving support 80.
and 78 are coupled to respective pairs of pools 102 and 78 adjacent to each other.

The driving means (not shown) has tension 1040 with one arrow 10.
This is coupled to rotate one of the goo IJ-102 so that the belt 100 moves in the direction of arrow 6 and the other tension 108 moves in the direction of arrow 100 opposite arrow 106.

Belt 100 also has a protrusion for the same purpose as protrusion 89 (FIG. 8).

The distance between the fiber guiding elements defined as the plate 12 in Figures 1, 4, 5 and 5a and the belting 72 in Figures 2 and 3 must be less than the average length of the wood fibers.

For the continuous belt of Figures 2 and 3, this distance is determined by the actual pulley dimensions.

The height of the fiber guide member influences the weight of the entire machine.

The increased height requires more tension per guide member and therefore makes the structure of the moving part of the device heavier.

For endless belts, this affects the dimensions of the pulleys.

If individual plates are provided on the frame, this increases the total mass to be moved.

This movement must be reciprocated with considerable amplitude and frequency.

Taking into account these factors and the fact that very low height fiber guides impair the degree of orientation, the optimum height of the fiber guide should be approximately equal to the maximum length of the fibers, but not the average length of the fibers. Even a fiber guide member having a height about half of the length can sufficiently orient the fibers.

The speed of movement of the fiber guiding member depends on the method used and whether the orientation of the fibers is parallel or perpendicular to the direction of movement of the support.

The amplitude of the reciprocating plate is also a factor and depends on the distance between the protruding elements and the length of the fibers.

When oriented in the direction of movement of the support, the fiber guide members rotate the fibers extending between the edges of two or more fiber guide members even at very low speeds, causing them to fall between adjacent fiber guide members, and this Good alignment can be obtained.

Even at the same low speed, clogging of the gap by wide pieces or bent fibers does not occur.

However, if a high throughput is desired, the speed of the fiber guiding member must be increased.

High speed supports do not adversely affect orientation.

The method of using a reciprocating plate attached to a frame is particularly attractive when oriented in the direction of movement of the support.

This is because the edge of each lower plate may be close to or in contact with the felt-like mat, whereas when oriented at right angles to the direction of movement of the support, the edge of the lower plate does not interfere with the felt-like mat. This is because the upper surface of the felt mat must not be approached to avoid damage.

In the case of orientation perpendicular to the direction of movement of the support, the speed of the fiber guide member is even more important.

Standing fibers having one end in contact with a support or felt-like mat and the other end in contact with a fiber guiding member must be drawn into orientation by the moving fiber guiding member faster than the moving support can pull the fibers out of orientation. .

The degree of orientation decreases with increasing support speed.

The speed of the fiber guide must therefore exceed the speed of the support in the case of orthogonal orientation.

A continuously moving belt provides a higher average speed than a reciprocating plate.

This method is therefore particularly useful for orientations perpendicular to the direction of movement of the support.

In order to avoid the fibers losing their orientation after leaving the space between the fiber guide members, the distance between the lower edge of the fiber guide members and the top of the felt-like mat must be kept to a minimum.

Therefore, the distance from the lower edge of the guide member to the moving support is the first
and should increase in the direction of support movement at approximately the same rate as the thickness increases during mat formation as shown in FIG.

This is true for both parallel and perpendicular orientations to the direction of movement of the support.

Protrusions 16 and 89 may be of various shapes and heights.

The distance between them is determined by factors such as the distance from one fiber guide member to the next adjacent member, the length of the fibers, and the overall process of the fiber guide members.

If the fibers extend over more than one edge of the fiber guide, the total stroke must be at least twice the distance from one projecting element to the other.

Otherwise, the fibers will not be sufficiently rotated and will collect on the upper edge of the fiber guide perpendicular to this.

An example of specifications for a good orientation device using fibers with an average length of about 5.08z is shown below.

Example 5.08cm fiber Maximum distance between long fiber guide members 1.59cm
〃 Thickness 0.06cyy+〃
〃 Height 5.08cfn Distance between protrusions 5.08crn Protrusion height 1.90cr I1 protrusion width
0.95 crn Total stroke 14.24 crn Frequency 300 strokes/min The length of the protrusion above the upper edge of the guide member is of great importance with regard to production output.

If the protrusions are short, it is not always possible to rotate the fibers extending across two or more edges of the fiber guide member so that they fall into the space between them.

This is especially true if large amounts of fiber fall onto the edges of the fiber guide member.

For example, a vertical projection (i.e., a projection with an edge at a 90° angle to the upper edge on the fiber guide member) with a length of 0.63 cIr1 to 0.196 rI1 will significantly increase yield, but further extensions is not appropriate.

If several fibers extend in the same location between two fiber guide members, a long protrusion will rotate all the fibers at the same time, rather than just the lower fiber.

Also, longer protrusions cause some fibers in the arc to be rotated before coming to rest between two or more fiber guide members, thereby increasing the proportion of fibers that fall directly between adjacent fiber guide members.

If the projections are longer, the fibers will be rotated faster and further than necessary, allowing the fibers to rest astride the guide members instead of falling between them.

Therefore, increasing the protrusion length beyond a certain maximum value does not increase the yield, and this optimum length depends on the speed of the fiber guide and the shape of the fibers, and in most cases about 2.54 CrIl is sufficient. .

The protrusions may have a variety of shapes, with serrations having gentle edges that are gentler on the fibers and less prone to breakage than vertical edges such as 45° diamond teeth.

This is important when at least some of the fibers are significantly longer than twice the distance between adjacent fiber guide members.

When a flexible belt is used continuously and long projections form part of or are fixed to the upper edge of the belt, it is necessary that these projections move with the belt around small pulleys.

They must be rigid in the direction of their length, yet sufficiently narrow or flexible in the direction of movement.

Tracking the belt over small pulleys is made more difficult by the long protrusion on the top edge.

The method of reciprocating the plates, which may be rigid, makes the use of long projections easier and also allows for higher yields.

The fiber guide members work best when in a vertical position and oriented parallel and perpendicular to the direction of movement of the support.

If the fiber guide members are deflected from the vertical position so that each fiber guide member acts as a slider, the degree of orientation is not improved but rather worsened.

In the case of movement of the support, this is of course a relative movement between the support and the fiber guide assembly.

Accordingly, either the fiber guide assembly or the support may be moved.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of one embodiment of the apparatus of the present invention, which includes a plurality of rigid parallel fiber guide members and binder-coated wood fibers passed between them so that the fibers are oriented in parallel. Figure 2 is a top view of a second implementation of the apparatus, showing the support of the mat receiving basin, through which the binder-coated wood fibers are passed to orient them before they fall onto the support; FIG. 6 shows an endless flexible belt extending in a number of passageways on a support to provide a plurality of parallel spaces for
FIG. 2a is a view similar to FIG. 2 showing another embodiment, FIG. 3 is a cross-sectional view taken along line 3--3 of FIG. 2, and FIG. 4 is a partial cross-sectional view of the device of FIG. 1. FIG. 5 is a partial top view of the device of FIG. 4, and FIG. 5a is a partial top view of the device of FIG. It is a figure which shows a part of adjacent fiber guide member and its frame in a different position. 12...Plate, 14...Support, 16.
...Protrusion, 18...Wood fiber, 20...
...Matt, 70... Endless belt, 72.
...Belt, 74...Pulley, 76,
78... side edge, 84... side wall, 89...
... Protrusion, 90 ... Drive pulley, 10
0...Endless belt, 100...Pulley.

Claims (1)

[Claims] 1. A group of elongated, substantially parallel spaces are provided above the support such that each pair of adjacent spaces has a boundary and a predetermined depth between them, and are aligned with said spaces. A block of loose wood fibers is threaded onto the space so that the wood fibers fall through the space and onto the support, corresponding to the fibers extending across the upper edges of each adjacent pair of boundaries. and rotating each adjacent pair of boundaries so as to rotate the fibers that engage the underlying fiber mat and the fibers that engage the boundary into substantially alignment with the longitudinal axis of said space. A method for orienting wood fibers or wafers parallel to a moving support to form a mat on a moving support, characterized in that they are moved in mutually opposite directions along substantially straight paths. 2. A plurality of substantially flat fiber guide members arranged parallel to each other at intervals, and coupled to the guide member for movably attaching pairs of adjacent guide members in mutually opposite directions and along substantially straight paths. means, a plurality of spaced fiber-engaging protrusions on the upper edge of the guide member, and means coupled to the guide member for moving the guide member along the path. Apparatus for orienting wood fibers and wafers relative to each other as they fall onto a moving support, characterized in that