1. Field of the Invention
The present invention relates to a method of processing wood according to which wood is processed into a three-dimensional shape, and a compressed wood product formed from wood through compression.
2. Description of the Related Art
In recent years, wooden materials that are natural materials attract attention. With a wide variety of grain patterns, wood products made of wood exhibit individual features depending on positions of the raw wood from which the particular wood products are cut out. Such individual features of each wood product give it a unique quality. In addition, surface flaws and discolorations caused by a long-term use create unique textures which tend to evoke warm and familiar feeling in the user. Thus, the wooden material attracts attention as a material for products of uniqueness and taste which cannot be found in products made of synthetic resin or light metals. Techniques for processing wooden materials are also developing dramatically.
According to one conventionally known technique for processing wooden materials: a wooden board is softened with water absorption and compressed; the compressed wooden board is cut along a direction substantially parallel with a direction in which the compressive force is applied, whereby a primary fixed product with a sheet-like shape is obtained; and the primary fixed product is deformed into a desired three-dimensional shape under heat and moisture (for example, see Japanese Patent No. 3078452 Publication). Further, according to another conventional technique, a softened wooden sheet is compressed and temporarily secured in a prepared mold and left in the mold until the wooden sheet recovers. Thus a wooden product with a desired shape can be obtained (see, for example, Japanese Patent Application Laid-Open No. H11-77619 Publication). According to these techniques, the thickness and/or the compression rate of the wooden material is determined based on various factors, such as individual specificity of each wooden material, type of wood, strength required in processed wood, and use of the processed wood.
A method of processing wood, according to one aspect of the present invention, in which a wooden piece is compressed into a predetermined three-dimensional shape includes compressing a portion of the wooden piece at a compression rate of at least 0.75 in a thickness direction of the portion of the wooden piece.
A compressed wood product according to another aspect of the present invention has a predetermined three-dimensional shape obtained through a compression process of a wooden piece, and includes a wooden piece that is at least a part of the compressed wood product and that has a translucent portion.
Preferred embodiments (hereinbelow simply referred to as “embodiments”) of the present invention will be described below with reference to the accompanying drawings.
The main plate portion 1a has a thin portion 11 which is formed as a truncated conical depression in an internal face (an upper surface in
The cover member 2, which covers a rear side (a side facing a photographer when taking a picture) of the digital camera 100, has substantially the same shape as the cover member 1. The cover member 2, similarly to the cover member 1, has appropriate openings and a cut-out portion to expose necessary components housed in the digital camera 100. For example, the cover member 2 has a semi-circular cut-out portion which has the same shape as the cut-out portion 14 and is formed at a corresponding position to the cut-out portion 14. When the cover members 1 and 2 are joined together for the assembly of the digital camera 100, the cut-out portion of the cover member 2 is joined together with the cut-out portion 14 of the cover member 1, and forms an opening to expose the shutter button 103.
The cover member 1 or 2 may have additional openings and cut-out portions in addition to those described above. For example, the cover member 1 or 2 may have an opening for an attachment of a finder, an opening to expose input keys through which the user gives instruction signals for operation, an opening or a cut-out portion to expose a connection interface (such as DC input terminal or USB connecting terminal) for an external device. Still further, the cover member 1 or 2 may have an audio output hole through which sound from the speaker embedded in the digital camera 100 can be heard.
A method of processing wood according to the first embodiment will be described. First, a wooden piece 41,is cut out from uncompressed raw wood (cutting-out process). The cut-out wooden piece is a raw material for the cover member 1. The volume of the cut-out wooden piece is larger than that of a finished piece by an amount to be decreased during a compression process described later. The raw wood to be employed may be selected, for example, from various types of wood, such as, Japanese cypress, hiba cedar, paulownia, Japanese cedar, pine, cherry, zelkova, ebony wood, bamboo, teak, mahogany, and rosewood depending on the use of the cover member 1.
The cut-out wooden piece may have a straight-grain surface, a flat-grain surface, an intermediate pattern between the straight-grain and the flat-grain, or an end-grain surface, and an optimal grain pattern can be selected according to the use of the compressed wood product. Therefore, the grain pattern of the wooden piece is not particularly shown in the drawings.
After the cutting-out process, the cut-out wooden piece is compressed (compression process). In the compression process, the wooden piece is left in water vapor atmosphere of high temperature and high pressure for a predetermined time period so that the wooden piece absorbs moisture in excess and is softened. Here, the high temperature means 100 to 230° C. and more preferably approximately 180 to 200° C. in temperature, and the high pressure 0.1 to 3 MPa (MegaPascal) and more preferably approximately 0.45 to 2.5 MPa in pressure. Alternatively, the wooden piece 41 may be heated by application of high-frequency electromagnetic wave such as microwave rather than by being left in the water vapor atmosphere as described above.
Thereafter, the wooden piece is placed in the same water vapor atmosphere as employed for softening and sandwiched between a pair of metal molds and is subjected to a predetermined amount of compressive force.
On the other hand, a metal mold 61 which is employed for applying a compressive force to the wooden piece 41 from below in
When the metal molds 51 and 61 and the wooden piece 41 placed between the metal molds 51 and 61 are viewed from +x direction towards −x direction along a section perpendicular to the section taken along line B-B of
It is known that when the wooden piece is compressed in the water vapor atmosphere of high temperature and high pressure as described above until the specific gravity thereof becomes approximately 1.5, the characteristics of the wooden piece alters. Under such condition, the wooden piece loses inherent characteristics of wood. For example, the grain patterns disappear and the wooden piece is fluidized (see, for example, Kitazawa, Kitamura, Shibuya, and Kojima, “Phenomenon of Permanent Fixation of Compressed Cedar Obtained by Consolidation nearly to Limit” 21th Annual Convention Proceedings, Wood Technological Association of Japan, 2003). When the wooden piece undergoes such alteration through compression, it substantially turns into resin, which exhibits tortoiseshell-like color tone and transmits light. Therefore, a wood product which has a translucent portion can be fabricated from one piece of wood without the use of a separate, transparent member as in the conventional art.
After the wooden piece 41 is left in the state shown in
For the clarification, examples of specific values are given. When the thickness R of the main plate portion 41a before the compression is 3.2 mm, and the thickness r1 of the main plate portion 41a after the compression is 1.6 mm, the compression rate C1 of the main plate portion 41a except for the thin portion 11 is 0.50. On the other hand, when the thickness r2 of the thin portion 11 is 0.80 mm, the compression rate C2=(R−r2)/R of the thin portion 11 is 0.75. When a further compression can be conducted within a range that would not compromise the strength of the wooden piece, the thickness of the thin portion 11 may be further decreased down to approximately 0.40 to 0.50 mm, to further enhance the transparency of the thin portion 11. Alternatively, for the enhancement of the transparency, the portion to be processed into the thin portion 11 may be initially formed so that the portion is thinner than other portions of the main plate portion, and the compression process may be controlled so that the compression rate in the thin portion is at least 0.75, and more preferably at least 0.80.
In the compression process described above, an appropriate driving unit may be provided to electrically drive at least one of the metal molds 51 and 61 to realize vertical relative movement of the metal molds 51 and 61. Alternatively, the metal molds 51 and 61 may be screwed with each other, so that the vertical relative movement of the metal molds 51 and 61 can be realized by manual or automatic screwing.
The compressed wood product according to the first embodiment is applicable as a jacket for electronic equipments other than a digital camera, for example, electronic equipments such as a portable communication terminal such as a portable telephone, personal handyphone system (PHS), and a personal digital assistant (PDA), a portable audio device, an IC recorder, a portable television, a portable radio, remote controls of various home appliances, and a digital video. When the compressed wood product is applied as a jacket for a small portable electronic equipment as listed above, the thickness after the compression may be preferably set to approximately 1.6 mm. When a light-emitting device is arranged in the electronic equipment so that the light-emitting device is located right inside the thin portion, the light emitted from such a device can be transmitted to the outside without the use of separate, transparent member.
According to the first embodiment as described above, a translucent property can be given to a portion of the wooden piece, i.e., the thin portion, since the compression process, which is performed to deform the wooden piece into a predetermined three-dimensional shape, is controlled so that the compression rate in the thin portion is at least 0.75 in the thickness direction. Therefore, even when the wood product is required to have a translucent portion, such wood product can be manufactured from a fewer parts through a fewer process steps. Thus, a more economical method of processing wood and a compressed wood product can be provided.
Further, according to the first embodiment, since the translucent portion is integrally formed with other portions from the same material, sealing quality of the compressed wood product can be enhanced compared with the product formed from separate members. When such compressed wood product is applied as a jacket for the electronic equipment, moisture can be prevented from intruding into the electronic equipment by capillary action between separate members.
A metal mold 71 shown in
The main plate portion 3a has two thin portions 31 each of which is thinner than other portions and has a star-shaped surface, a circular opening 32 that is arranged between the two thin portions 31 and exposes the image pick-up unit 101, and a rectangular opening 33 that exposes the photoflash 102. Further, the side plate portion 3b has a semi-circular cut-out portion 34.
A portion of the wooden piece abuts the protruding portion 73 of the metal mold 71 and is compressed between the protruding portion 73 of the metal mold 71 and the depression 62 of the metal mold 61, and turns into the thin portion 31 which transmits light similarly to the thin portion 11 of the first embodiment. In the second embodiment, since the slope 73c of the protruding portion 73 formed in the metal mold 71 forms a gently curved surface, a slope 31c extending from the bottom portion 31a, which is the thinnest in the thin portion 31, to the outer rim 31b gradually becomes thicker. Hence, the compression rate of the thin portion 31 in the main plate portion 3a, is the highest in the bottom portion 31a and gradually decreases towards the outer rim 31b. Specifically, the compression rate of the bottom portion 31a is at least 0.75 and more preferably at least 0.80, while the compression rate of the outer rim 31b is, similarly to the compression rate of other portion in the main plate portion 41a, approximately 0.40 to 0.70, and more preferably approximately 0.50 to 0.70.
When light is incident on the thin portion 31 with the above-described configuration, the transmitted light changes its tone gradually from the bottom portion 31a to the outer rim 31b. For example, light transmittance is the highest in the bottom portion 31a, which is the thinnest, and gradually decreases towards the outer rim 31b; in other words, the transmitted light gradually becomes weaker from the bottom portion 31a towards the outer rim 31b. The combination of the variation in light transmittance and the variation in tortoiseshell-like color tone generated by compression and varied according to the thickness gives a subtle gradation to the star-like pattern of the thin portion 31. Through the control of the temperature and pressure of the water vapor atmosphere employed at the compression, various types of gradation can be realized, which further grants individual features to each compressed wood product.
A feature of the second embodiment lies in that wood processing is performed so that a portion which is transformed into the resin-like state through compression and a portion which remains woody even through compression are present in the same product side by side, and a product with more sophisticated design is provided. Therefore, in the second embodiment, the resin-like portion does not require as large a transparency as the thin portion of the first embodiment. Hence, the bottom portion 31a of the cover member 3 is not necessarily as thin as the thin portion 11 of the cover member 1.
According to the second embodiment as described above, even when the wood product is required to have a translucent portion, such wood product can be manufactured from a fewer parts through a fewer process steps, similarly to the first embodiment. Thus, a more economical method of processing wood and a compressed wood product can be provided.
Further, according to the second embodiment, since the protruding portion of the metal mold has a gently curved slope, the thin portion of the compressed wood product may have a tone gradation, which contributes to improve the design of the compressed wood product. Hence, the method of processing wood according to the second embodiment is also suitable for the processing of the compressed wood product other than jackets of the electronic equipments. For example, the method of the second embodiment can be applied to the processing of casings such as a case for glasses and a powder compact, and accessories.
Needless to say, the shape and the number of the protruding portions formed on the metal mold are determined according to various conditions, such as the shape or use of the finished compressed wood product, and the type of wood to be employed.
In the third embodiment, since the vase 21 has the thin portion 211 as described above, the amount of water in the vase 21 can be visually confirmed from outside. Further, in the third embodiment, since the thin portion 211 is formed integrally with other portions of the vase 21, there is no junction where a separate, transparent member is adhered to other portion, whereby the sealing property of the vase can be improved and the water inside the vase 21 can be prevented from leaking to the outside.
In
A compressed wood product according to another modification of the third embodiment may be a covering member (not shown) for a main body of a pot. Such covering member may have a thin portion at a position corresponding to a water meter provided on the pot to indicate the amount of water contained in the pot, so that the water meter can be seen from outside when the covering member is attached to the pot. In this case, the entire main body of the pot may be formed from a transparent material, or only the water meter may be formed from a transparent material. In either case, the amount of water inside the pot can be visually confirmed from the outside via the thin portion.
The compressed wood product according to the third embodiment can be formed through compression similarly to the compressed wood products of the first and the second embodiments with the use of metal molds that are shaped corresponding to the finished shape of the compressed wood product in the water vapor atmosphere of high temperature and high pressure. The same applies to a fourth embodiment to an eighth embodiment described below.
On a side surface of the main body 231, a translucent thin portion 233 is formed along a vertical direction of
Here, instead of the cap 232, a cap having a spout for liquid may be attached to the main body 231. Then, a caster for liquid seasoning such as soy sauce or vinegar can be configured.
When the thin portion 233 is horizontally formed along substantially the entire periphery of the main body 231 instead of along the vertical direction, the caster may serve as a toothpick holder. In this case, the holes in the cap 232 may be formed slightly larger than the diameter of the toothpick.
The lamp shade 242 is formed by conducting the compression of a wooden piece of substantially uniform thickness taken from the raw wood so that the compression rate in the thickness direction is at least 0.75 and more preferably at least 0.80. The lamp shade 242 transmits light emitted from the electric bulb attached to the support base 241. For example, when a metal mold is configured so that the compression rate in the thickness direction of the wooden piece of the lamp shade 242 gradually increases downward in
In the above description, the wooden piece with a uniform thickness is taken out from the raw wood as a material for the lamp shade 242. Alternatively, at the formation of the lamp shade 242, the wooden piece may be cut out from the raw wood in such a manner that the thickness of the wooden piece gradually changes. Then, the thickness of the wooden piece may be made substantially uniform through the compression. Here, depending on the types of the wood employed for the lamp shade 242, setting of the compression rate of the whole portion to at least 0.75 may compromise the strength of the finished product. Hence, the compression rate may be set lower than 0.75 in some portions so that the strength of the finished lamp shade 242 can be properly maintained.
The thin portion 253 is formed by compressing a wooden piece so that the compression rate in the thickness direction is at least 0.75 and more preferably at least 0.80, and transmits light. Hence, the light emitted from the electric bulb arranged inside the main body 251 passes through the thin portion 253 and illuminates the surroundings. The roof portion 252 may be formed from wood or from other materials such as metal and synthetic resin.
According to the sixth embodiment, the compressed wood product can serve as lighting which illuminates the plants in the garden at night by an appropriate amount of light. Further, since the thin portion 253 is formed integrally with the main body 251, moisture does not come inside the main body 251 at the watering of the plants.
In the table 28 with the above-described configuration, since the thin portion 284 is formed integrally with the tabletop 281, even when water or the like is spilled over the tabletop 281, the water or the like does not come through the thin portion 284 and reach a portion below the thin portion 284. Therefore, water or the like can be properly removed only by wiping off the tabletop 281. Thus, the table 28 can be easily maintained in condition and is hygienic.
At the cutting-out of the tabletop, the thickness may be made uneven, and the compression may be performed so that the compression rate at a thickest portion before the compression is at least 0.75 and more preferably at least 0.80. Then, the tabletop obtained by the compression exhibits a marble-like pattern formed by combination of translucent portions and opaque portions. Thus, the electric bulb or the like arranged in the base 282 can give gradation of illumination seen on the tabletop.
The exemplary embodiments of the present invention are described in detail above as the first to the eighth embodiments. It should be noted, however, that the present invention is not limited to the eight embodiments described above. In other words, the present invention can include various embodiments not described particularly herein, and various modifications in design or the like can be made without departing from the scope of the technical concept defined in the appended claims.
Number | Date | Country | Kind |
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2005-229843 | Aug 2005 | JP | national |
2006-010228 | Jan 2006 | JP | national |
This application is a continuation of PCT international application Ser. No. PCT/JP2006/306374 filed Mar. 22, 2006 which designates the United States, incorporated herein by reference, and which claims the benefit of priority from Japanese Patent Applications No. 2005-229843, filed Aug. 8, 2005; and No. 2006-010228, filed Jan. 18, 2006, incorporated herein by reference.