JPH0576422B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method of expanding a non-metallic honeycomb core.

"Prior Art" and "Problems to be Solved by the Invention" Regarding the method of expanding a non-metallic honeycomb core (hereinafter simply referred to as "honeycomb core"), for example,
A drawing process in which a honeycomb core formed in an endless shape in an end-expanded state is expanded while being narrowed to a predetermined width by a drawing device configured to squeeze the end-stretched honeycomb core sequentially from one end toward the ribbon from both sides; The honeycomb core that has undergone the expansion process is further expanded slightly using a stretching machine having a rotating belt in which a large number of sharp-shaped protrusions that are shorter than the thickness of the honeycomb core and are implanted at appropriate pitches are used to expand the honeycomb core. A method is provided as Patent No. 1295354 ``Method for expanding honeycomb core''. However, in this method, although it is possible to continuously expand the honeycomb core using a simple stretching device, it is particularly difficult to expand the honeycomb core in the final expanded state formed by a material sheet that is strong and has elasticity. When a honeycomb core is expanded by such a method, it is difficult to obtain permanent bending deformation in the material sheet, and the expanded honeycomb core has a restoring force due to the influence of outside air conditions such as humidity and the elasticity of the material sheet. It has been difficult to mold a honeycomb core with stable dimensions because it tends to change over time.
Therefore, there is a drawing step in which an endlessly-formed honeycomb core in an end-expanded state is expanded from one end while being narrowed in the ribbon direction, and then the honeycomb core in this expanding process is further expanded in heated steam. Japanese Patent Application No. 56-67245 discloses a method of expanding honeycomb cores through a heating, humidifying step of rolling, heating and humidifying the honeycomb core, and a drying step of drying the heated honeycomb core. JP-A-57-181848) ``Method for forming non-metallic honeycomb core and expansion heating humidification device used to carry out this method''. but,
Although the honeycomb core expanded by this method has excellent dimensional stability,
The expansion molding apparatus is large and complicated, requires a considerable amount of installation space, and is expensive, so it has the disadvantage that it cannot be easily installed anywhere. Furthermore, the expanded honeycomb core is very bulky relative to its weight, which increases shipping costs, making the honeycomb core extremely expensive. Therefore, for example, when purchasing and processing expanded honeycomb cores, the product cost is high.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to form a honeycomb core with excellent dimensional stability anywhere using a simple structure expanding device. The purpose is to provide a method for expanding the core.

"Means for Solving the Problem" The present invention has been made to achieve the above object, and its technical solution is to sequentially connect a honeycomb core formed in a state of tension to one end of the honeycomb core. The strip-shaped material sheets constituting the material are pressed together along the longitudinal direction (ribbon direction) so as to be crushed.
a folding step of forcibly folding the honeycomb core in the ribbon direction to form folds for forming cell walls at predetermined portions of each of the strip-shaped material sheets, and then folding once to form the folds. The folded honeycomb core is expanded in a ribbon direction in a stretching step to expand the honeycomb core in a fully expanded state to form a honeycomb core.

"Function" Since the present invention consists of the above means, it works as follows. In other words, when a honeycomb core in an end-stretched state is forcibly folded in the direction of the ribbon in the folding process, the maximum bending moment acts on a predetermined portion of each material sheet, that is, on one side edge of the bonded part. The material sheets are bent by 180 degrees at these locations, and creases are formed in each material sheet to form the cell walls of the honeycomb core.

In the folding process, each material sheet is temporarily folded by 180 degrees to forcibly form a folding pattern. Due to the permanent bending deformation of the material formed when it is forcibly folded, a bend at a predetermined angle is formed in the bend formed along one side edge of the adhesive part. . The bending angle of the folded part formed by this fold is further bent than the bending angle for forming the cell walls at the time of the predetermined expansion of the honeycomb core. In the process, when forming a honeycomb core by expanding the honeycomb core in the ribbon direction, the honeycomb core is expanded in such a way as to stretch the folded part that has been folded excessively and permanently bent. It is extremely easy to expand, and the molded honeycomb core already has sufficient folds.
Its dimensions hardly change over time.

"Example" The present invention will be described below based on an example shown in the drawings.

In FIG. 1 to FIG. 4, 1 is a honeycomb core formed in an endless shape and in an end-expanded state;
The honeycomb core 1 in the fully expanded state is constructed as follows. That is, by an appropriate well-known manufacturing method, a predetermined number of strip-shaped material sheets 2, 2... formed of non-metallic materials such as paper materials are stacked with adhesives 3, 3... at positions alternately shifted by half a pitch. It is formed by connecting a large number of unit end-stretched honeycomb cores 4, 4... by adhesive.

The honeycomb core 1 in the end-expanded state formed in an endless shape is arranged so that the interval forming the folding process can be adjusted, and the honeycomb core 1 in the end-expanded state is sent out while being folded by an appropriate driving means (not shown). A folding device 5 having a pair of compression rollers 6, 6 having a height higher than the thickness T of the honeycomb core 1 in an end-expanded state and arranged to rotate in the direction of the arrow in Fig. 2).
Starting from one end, each of the strip-shaped material sheets 2, 2, . That is, when folding the honeycomb core 1 in the end-expanded state in the folding process in the ribbon direction L, first, the compression roller 6, Then, one end of the honeycomb core 1 was brought into contact with the compression rollers 6, 6 so that the center between the compression rollers 6, 6 and the center of the honeycomb core 1 in the end-stretched state in the ribbon direction L substantially coincided with each other. After that, the center of one end of the honeycomb core 1 in the end-stretched state is grasped and the end of the honeycomb core 1 is forcibly moved between the compression rollers 6, 6 in a direction perpendicular to the center line connecting the compression rollers 6, 6. After the honeycomb core 1 is passed through and pulled out, the compression rollers 6, 6 are driven, so that the honeycomb core 1 in the end-stretched state is sequentially compressed by the compression rollers 6, 6 into each band-shaped material sheet 2 constituting the honeycomb core 1 in the end-stretch state. , 2... are sent out while being folded along one side edge of each bonded portion 7, 7....

The honeycomb core 1b sent out from the folding device 5 and in the process of being expanded is restored by a predetermined amount by the restoring force due to the elasticity of the material so that the folded portions are sequentially opened, and the planar shape of each cell 8, 8... is approximately rectangular. The honeycomb core 1b is formed during the expansion process, and the width is narrower in the ribbon direction L than when it is expanded to a predetermined extent. Next, the honeycomb core 1b in the stretching process is applied to an appropriate stretching means, for example, in the ribbon direction L of the honeycomb core 1b in the stretching process.
A honeycomb core 10 having a predetermined width in the ribbon direction L can be continuously formed by sequentially gripping both ends of the core and applying a stretching tension P to the ribbon so as to pull it in the ribbon direction L.

Next, this continuously formed honeycomb core 1
A honeycomb core of a predetermined size is obtained by cutting 0 into predetermined lengths in a cutting process (not shown).

Note that 9, 9... are cell walls forming the cells 8, 8....

In the above-mentioned embodiment, the honeycomb core 10, which is formed in an endless shape and is in an end-expanded state, is continuously folded and expanded to form the honeycomb core 10 continuously, and the honeycomb core 10 is shaped into the honeycomb core 10 for each predetermined size. Although the method of forming a honeycomb core of a predetermined size by cutting into a honeycomb core of a predetermined size has been described, the configuration of the honeycomb core in the end-expanded state and the cutting process are not limited to the examples. The honeycomb core 1a is cut into predetermined lengths after the folding process, and the honeycomb core 1 is restored by the restoring force of the cut material.
The honeycomb core may be formed by stretching b in the ribbon direction L, or the honeycomb core may be folded and stretched every unit end-stretched honeycomb core 4.

"Effects of the Invention" As described in detail above, according to the method for expanding a non-metallic honeycomb core according to the present invention, a material sheet in an end-expanded state formed of a material sheet made of a non-metallic material having strong stiffness and elasticity can be used. Even for honeycomb cores, non-metallic honeycomb cores with excellent dimensional stability can be formed anywhere using a simple stretching device, reducing equipment costs for the stretching device and transportation costs. It has become possible to reduce the amount of heat generated by the honeycomb core, and the drawbacks of conventional methods for expanding honeycomb cores of this type have been wiped out.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and Fig. 1 is an explanatory diagram of a non-metallic honeycomb core formed in an endless shape in an end-expanded state, and Fig. 2 is an illustration of the main parts showing each step of the elongation method. 3 is a detailed plan view of section A in FIG. 2, and FIG. 4 is a detailed plan view of section B in FIG. 2. 1 is a non-metallic honeycomb core formed in an endless shape and in an end-stretched state; 1a is a honeycomb core that is passing through a folding process; 1b is a honeycomb core that has been restored after passing through a folding process; 2 is a strip-shaped material sheet;
3 is an adhesive, 4 is a unit end-stretched honeycomb core, 5 is a folding device, 6 is a compression roller, 7 is an adhesive part, 8 is a cell, 9 is a cell wall, 10 is a honeycomb core, L is a ribbon direction, and P is an expansion Tension, T is the thickness of the honeycomb core.

Claims (1)

[Claims] 1. A non-metallic honeycomb core formed in an end-stretched state is pressed against one end of the non-metallic honeycomb core so as to be crushed along the longitudinal direction (ribbon direction) of each band-shaped material sheet constituting the non-metallic honeycomb core, and A folding step of forcibly folding the non-metallic honeycomb core in the direction of the ribbon in order to form folds for forming cell walls at predetermined portions of each strip material sheet; A method for stretching a non-metallic honeycomb core, comprising the step of stretching the non-metallic honeycomb core that has been folded as far as possible in a ribbon direction.