JPH06254814A - Forming method for timber - Google Patents

Abstract

PURPOSE:To improve the productivity and economical efficiency in the high level utilization of a timber from thinning by compressing the timber almost to the thickness of given shape, inserting the timber into a frame of given shape, reducing the pressure and forming by means of the restoring force of the timber. CONSTITUTION:A timber 3 is stored in a tank chamber consisting of a high pressure tank 1 and a tank cover 2 and pressurized to the given pressure by a fluid pressure source 7 through a valve 8. The timber 3 with its volume reduced by pressurizing is stored between split molds 4-1 and 4-2, and integrated by frame tightening devices 6-1 and 6-2 and fixed. After that, a fluid discharge valve 13 is released to release the pressure in the tank, and the timber 3 is expanded following the shape of the molds 4-1 and 4-2 and formed. The timber is taken outside together with the frame in the above-said state, and its shape can be stabilized by applying the proper processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to forming wood used for construction and woodworking.

[0002]

2. Description of the Related Art Wood used for construction and carpentry is usually formed by cutting a circular log material into a predetermined shape by cutting, and recently, due to high utilization of thinned wood, the thermoplasticity of the material has been improved. A molding press method using the is studied. The present invention relates to the improvement of the pressing method.

[0003]

In the press molding method,
In the case of normal pressurization, it is recommended to apply uniform pressure from the outer circumference of the material, and it is considered to be good to avoid slipping on the press contact surface. Therefore, the pressing method has a limit in forming various kinds of products such as polygons other than simple quadrilaterals, ellipses, and deformed shapes.

[0004]

[MEANS FOR SOLVING THE PROBLEMS] A material and a mold formed into a predetermined shape are inserted into a high pressure tank capable of depressurizing, and pressure is applied until the outer diameter of the material is large enough to fit in the mold. , A method of storing in a mold in a tank, decompressing, and adapting to the mold by the internal stress of the material to mold. The method of preheating and secondary heating of the raw material for molding is according to the conventional technique.

[0005]

The feature of the present invention is not the molding method by the molding pressure from the outside but the method by the restoring force of the uniformly pressed and compressed material, which is used for the deformation applied to each part of the material during the molding. Since the force is only the restoring force accumulated inside, it is possible to avoid the influence such as the frictional resistance of the outer skin contact portion which occurs in the former case.

A description will be given below with reference to the drawings. FIG. 1 shows a vertical section of a molding apparatus according to the present invention. The material 3 is housed in a tank chamber composed of a high pressure tank 1 and a tank lid 2, and is pressurized to a predetermined pressure from a fluid pressure source 7 via a pressure reducing valve 8. As shown in FIG. 2, the material 3 has a structure in which the end face is communicated with the outside and the sap is easily discharged due to the volume reduction of the material generated when being pressurized.

The material 3 whose volume has been reduced by pressurization is housed between the divided molds 4-1 and 4-2, and the mold tightening device 6-1.
And 6-2 to fix together. After that, by releasing the fluid discharge valve 13 and releasing the pressure inside the tank, the material 3 is expanded and molded along the shapes of the molds 4-1 and 4-2. In this state, the shape can be stabilized by taking it out together with the mold and applying an appropriate treatment.

In the figure, the sealing material 5 covering the outer peripheral portion of the material 3 is sometimes used to prevent the fluid from penetrating into the material depending on the type of the pressurized fluid. Or wrap a wrapping material.

The seal 15 shown in the cross-sectional view of the apparatus of FIG. 2 is for preventing the leakage of the fluid b from the gap between the material 3 and the tank 1 at the time of pressurization. A communication hole a is provided so that the fluid b can flow into the inside of the seal 15 in order to follow the decrease in the diameter. The seal holder 16 plays a role of fixing the seal 15 and holding the material 3 in a fixed position.

In the figure, a pressure gauge 9 is for monitoring the pressure of the fluid supplied through the pressure reducing valve 8, and 10 is a variable throttle valve for controlling the pressurizing speed, and 11
Is a temperature controller for controlling the temperature in the pressurized tank, 1
Reference numeral 2 is a thermometer for monitoring the temperature, and 14 is a recovery equipment for decompressing or discharging the fluid in the tank.

[0011]

[Effect] This method, which has a simple structure of compressing a material with a high-pressure fluid and forming it by its internal repulsive force, is believed to contribute greatly to the improvement of productivity and economic efficiency in the advanced utilization of thinned wood.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of an apparatus embodying the present invention.

FIG. 2 is a cross-sectional view taken along the line II in FIG.

[Explanation of symbols]

1 High-pressure tank 2 Tank lid 3 Material 4-1 Form 4-2 Form 5 Sealing material 6-1 Tightening device 6-2 Tightening device 7 Fluid pressure source 8 Pressure reducing valve 9 Pressure gauge 10 Variable throttle valve 11 Temperature controller 12 Thermometer 13 Fluid discharge valve 14 Fluid tank 15 Seal 16 Seal holder a Communication hole b Fluid

Claims (1)

[Claims] 1. When pressure molding is performed by utilizing the thermoplasticity of a fibrous material such as wood, the material is compressed to a thickness of a predetermined shape and then inserted into a mold of a predetermined shape to reduce the pressure. Then, the method of molding by the restoring force of the material.