RU2232838C1 - Matrix for forming of products from fibrous pulp - Google Patents

Abstract

FIELD: processing of waste paper for producing of three-dimensional articles from fibrous suspensions and equipment for manufacture from fibrous pulp of complicated shape articles in small amounts or batches.

SUBSTANCE: matrix has working surface defined by open end surfaces joined with side surfaces of ganged members arranged perpendicular to basic forming surface, and drain apertures defined by gaps between ganged members. Ganged members are made in the form of cylindrical rods of equal length and section. Cylindrical rods are arranged in mutually parallel relationship to define drain apertures formed as through channels disposed between at least three rods. Rods are arranged for mutual displacement and fixation with respect to one another for modeling and sizing of working surface in three coordinate axes.

EFFECT: reduced costs and time for working out and industrial development of novel products, including small-scale products and products of intricate construction, intensified and effective operation of vacuum and pneumatic equipment in product formation processes.

8 dwg

Description

The invention relates to the field of processing recycled paper raw materials and the industrial production of bulk products from fiber suspensions, and directly relates to the process and equipment for the manufacture of products from molded pulp predominantly complex shapes in small quantities or in small batches.

A device is known for forming shaped articles of fibrous material, including a set of plates of the same contour of the cross-section with working edges forming the product forming surface and non-working edges and an adjustable clamp for fastening the plates with a gap between adjacent planes of the plates [Description of the invention to US patent No. 1984384, N .Cl. 92-57, publ. 12/18/1934 Official Gazette US, Vol.449].

To create such a device, it is necessary to produce many single plates, which differ from each other in the height of a given profile from the base of the plate. This feature makes the manufacture of the device low-tech. In this case, the suction of liquid from the fibrous suspension in this device at different sites can occur unevenly, depending on the geometric dimensions of the gaps between the plates, which are mostly random in nature. In this regard, products of stable quality cannot be obtained on this device.

The closest to the essential features of the claimed device is a device (matrix) for forming profiled products from fibrous material, including a package perpendicular to the base surface (the surface on which the form is installed, it is also a horizontal plane or a mirror of the surface of the paper pulp, or fibrous suspension ) a set of plates (typesetting elements), the same contour of the section with the working edges forming the product molding surface, and non-working edges and an adjustable clamp for fastening the plates with a gap (with drainage holes) between adjacent planes of the plates, while the non-working edges of the plates have a contour of the working edges, and the plates with adjacent planes are displaced one relative to another so that the surface formed by non-working edges corresponds to the molding surface of the product [ Description of the invention to the patent of the Russian Federation No. 2085646, IPC ⁶ D 21 J 7/00, publ. 07.27.97, Bull. No. 21]. In the design of the device, there are rich possibilities for changing the sizes of products when using the same plates due to their relative displacement to a new depth, i.e. proportional change in the transverse profile of the product along two coordinate axes, regardless of the section.

This device can be used for molding products with a periodic surface profile. For molding products with a complex spatial form and non-repeating structural elements, this device cannot be used, because the complexity of its manufacture increases significantly and the possibility of conversion to other sizes is limited, where it may be necessary to fine-tune the working surface not in two, but in three coordinate axes.

The problem solved by the invention and the obtained technical result consists in providing the process of molding fiber products with a universal means of modeling and mass production of new products, including small batches of products of structurally complex shape, which will reduce costs and reduce the time of its development and industrial development. In addition, it provides faster and more efficient operation of vacuum and pneumatics in the process.

To solve the problem in the known matrix for molding products from fibrous mass, including a working surface formed by an array of open end and mating side surfaces of the stacked elements perpendicular to the molding base surface, and drainage holes formed by the gaps between the stacked elements, the latter are made in the form cylindrical rods of equal length and equal cross-section, arranged mutually in parallel with the formation of drainage holes in the form of through channels between at least three of the rods, while the stacking elements are mounted with the possibility of mutual movement and fixation relative to each other for modeling and fine-tuning the working surface along three coordinate axes.

The invention is illustrated by drawings, where:

figure 1 shows a cross section of a device for forming articles of fibrous mass;

figure 2 shows a fragment of the working surface of the device;

figure 3 and figure 4 shows the design of the drainage holes;

figure 5 - figure 8 illustrate the process of aligning the working surface of the device for forming articles of fibrous mass on two-dimensional patterns, namely:

figure 5 shows a basic three-dimensional computer model of the working surface of the device;

figure 6 shows the process of dissecting a three-dimensional model into two-dimensional patterns;

figure 7 - image output patterns on an accessible material medium;

on Fig - the process of building one of the layers of the working surface of the device according to the pattern.

The matrix for molding articles of fibrous mass includes a working surface 1 formed by an array of open end 2 and mating lateral 3 surfaces of the stacked elements 4, perpendicular to the molding base surface 5, and drainage holes 6 formed by the gaps between the stacked elements 4, which are made in in the form of cylindrical rods of equal length and equal cross-section, arranged mutually in parallel with the formation of drainage holes 6 in the form of through channels between at least three of the rod 4, the rods 4 are mounted for reciprocal movement and fixation relative to each other for the simulation and debugging work surface 1 along three coordinate axes X, Y and Z.

In this form, the matrix is part of the molding section (technological device of the next level). The section is connected to the mains for supplying vacuum, compressed air, etc., as well as to other elements of the technological line for manufacturing products from fibrous mass.

Molding products on this matrix includes washing the mass, deposition of the fiber on the working surface of the molding 1 under the action of vacuum, draining the excess fiber mass, the final deposition of the remaining mass on the working surface 1, the maximum possible dewatering of the workpiece, the supply of compressed air, “shooting” of the raw product and its transfer to subsequent drying using a transport conveyor (not shown conditionally).

The matrix for molding articles of fibrous mass is made of stacked mutually parallel cylindrical rods 4 of equal length and the same cross section perpendicular to the molding base surface 5. The cylindrical rods 4 can be made of materials whose density ranges from 500 kg / m ³ and above, compressive strength from 20 N / mm ² and above, bending strength from 20 N / mm ² and above, and Shore hardness - from 65 D and higher, for example from brass grade L63. These rods 2 are stacked in layers into the mounting frame 7, forming an working surface 1 of the matrix with an array of open end 2 and conjugate side 3 surfaces. Technological drainage holes 6, necessary for sucking off excess moisture from the moldable pulp and for operating a pneumatic system for unidirectional shooting of a crude product onto a conveyor conveyor by parallel streams of compressed air, are formed by through gaps between four (Fig. 3) or three (Fig. 4) cylindrical rods 4 matrices.

The maximum possible depth of the final product, made on a universal matrix, is determined on the basis of 1/2 the length of the rod minus the height of the mounting frame 7 along the clamping face 8.

The drainage properties of the matrix composed of rods 4, in comparison with matrices of a traditional design, are higher in both quantitative and qualitative indicators. In the traditional process of molding fiber products, the ratio of the total area of drilled drainage holes to the total area of the molding surface is on average 6-8%. For a matrix whose molding surface 1 is composed of rods 4 with the stacking shown in FIG. 3, the ratio q _{p4 of the} total area S _{h4 of the} drainage holes 6 to the total area S _{matrix of} the molding surface 1 (for end surfaces 2) is calculated by the formula

q _p4 = S _h4 / S _matrix = 1-π / 4

and makes up more than 21%.

For a matrix whose molding surface 1 is composed of rods 4 with the stacking shown in FIG. 4, the ratio q _{p3 of the} total area S _{h3 of the} drainage holes 6 to the total area S _{matrix is} calculated by the formula:

)q _p3 = S _h3 / S _matrix = 1-π / (2 ×

)

and makes up more than 9%.

The drainage holes 6 of the matrix are unidirectional and oriented perpendicular to the base molding plane, which ensures quick and effective suction of excess moisture from the workpiece, as well as its uniform ejection by parallel streams of compressed air.

Depending on the design problem and the initial data, the matrix for the manufacture of molded products from pulp is built in one of the following ways.

Example 1. Layer-by-layer matrix alignment according to two-dimensional patterns (splines).

This method is applicable for three-dimensional computer modeling of the molding surface 1. The basic three-dimensional computer model (Fig. 5) is longitudinally dissected into two-dimensional splines with a step t (Fig. 6) equal to the diameter d of the rods 4 of the matrix — t = d — for four rods, or t = d × √3 / 2, which is approximately t = 0.866 × d - for three rods. The dissection algorithm is similar to that used in stereolithography. In the method under consideration, each spline is preliminarily printed on any available medium, for example, paper or transparent film for printers (Fig. 7). Next, the rods 4, parallel located on the plane, are lined with vertices along the spline forming line (Fig. 8). The resulting layer is transferred to the mounting frame 7, after which the cycle of operations is repeated again until the entire molding surface 1 of the matrix is lined up with the end surfaces 2 and the side surfaces 3 of the rods 4 connected to them. The resulting array of rods 4 is finally fixed in the frame 7 with clamps (not shown conditionally).

Example 2. Segmented matrix alignment using three-dimensional punch primitives.

If the designed product contains several repeating elements, then segment-wise alignment is used instead of layered. For this, a three-dimensional punch primitive is prepared, on the forming surface of which the vertices (end surfaces 2) of the cylindrical rods 4 are lined up, forming a finished segment. An array of rods 4 of each obtained segment is temporarily fastened, for example, using water-soluble surgical threads. The segments fit into the mounting frame 7 and tightly clamped with clamps. After this, the matrix is placed in water, where the dissolution of the threads fastening each segment takes place. As the threads dissolve, the mounting frame 7 is pulled together with clamps until the cylindrical rods 4 of the matrix are fully fixed.

Example 3. Alignment of the matrix according to the finished solid model.

In the event that there is a ready-made solid model of the surface of the product planned for production, the rods 4 of the matrix are simply lined up on it. The advantage of using rods 4 of the same length is that for this method, you can build on both the end working edges 2 and non-working edges 9 of the cylindrical rods 4.

The matrix is used as follows.

The forming section with the matrix is located above the bath with a pre-prepared (washed) two percent suspension of paper fiber in water, and the matrix is located with the ability to make reciprocating movements in a vertical plane. In the lower position, the matrix is completely immersed in the suspension, in the upper position it leaves the suspension to the position of the possibility of transferring the product to the transport conveyor, including through an intermediate transmission to the punch.

When the matrix moves down, it is immersed in the suspension. During immersion from the side of non-working edges 8 of the rods 4, a vacuum is applied. Water begins to leak through holes 6, and the pulp begins to settle on the molding surface 1. Having reached a lower point in its motion, the matrix begins to rise. Upon exiting the suspension, excess fiber is drained back into the bath. The effect of vacuum on the pulp continues. By the time the matrix approaches the top dead center, the product is dehydrated as much as possible. At a certain moment, the matrix is disconnected from the vacuum, instead of which compressed air begins to be supplied, which “shoots off” the still crude product onto the transport conveyor, after which it enters the final dryer.

With further movement of the matrix, the process repeats.

Using the inventive matrix, it is possible to quickly manufacture a small batch of high-quality packaging of a rather complex shape, for example, packaging for special devices.

Thus, the use of the invention provides a process for molding fibrous products with a universal means of modeling and production. In addition, the invention allows to reduce costs and reduce the time of development and industrial development of new products, including small-scale and structurally complex products, provides faster and more efficient operation of vacuum and pneumatics in the technological process of forming products.

Claims (1)

A matrix for molding articles of fibrous mass, including a working surface formed by an array of open end and mating side surfaces of the stacked elements perpendicular to the molding base surface, and drainage holes formed by the gaps between the stacked elements, characterized in that the stacked elements are made in the form of cylindrical rods of equal length and the same cross section, mutually parallel with the formation of drainage holes in the form of through channels between at least it with at least three of the rods, while the typesetting elements are installed with the possibility of mutual movement and fixation relative to each other for modeling and fine-tuning the working surface along three coordinate axes.

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