Note: Descriptions are shown in the official language in which they were submitted.
~ 5~
The inven-tion relates to a stringed instrument, and more
particularly, to a neck attached to a sound box for supporting
strings of a guitar.
A usual stringed inskrurnent has a neck body on which a
finger board supporting fre-ts is mounted and which has its one
end integrally connected with a peg llead and its other end formed
with an integral limb for connection with the sound box. The
re~uirement on the neck is its high strength which is sufficient
to wi-thstand a high tension in the strings and to prevent the
strains from occurring over a prolonged period of use. On the
other hand, it is desired that the acoustic attenuation be minimized
in view of the delicate influence upon the tone quality. A
converltional neck comprises a solid member formed of a maple--tree.
However, a high degree of skill and experience is required in
the selection of the grain or its orientation when cutting the
wood into a scluare timber or slab and cutting the lat-ter into the
form of the neck. The final quality of the resulting products
is greatly influenced by such skill if they are formed from the
single wood. Another difficulty with the conventional neck
material is the tremendous length of the seasoning period required
from tlle lumbering of the wood until a product is finished. When
producing an ordinary class product, the seasoning period by
; natural drying will be nearly three years at the wood level, t.wo
years at the timber or slab level and about one year after a rough
machining. This implies the necessity of paying an attentive
consideration to the procurement of the wood and the control over
the production steps. Though the natural dryi3lg may be replaced
by a forced drying, it is highly desirable to have the natural
seasoning ~eriod at the wood and the timber levels in order to
minimize the strains which might be caused by the aging effect.
A furtller disadvantage which occurs with the use of the solid neck ;~
material is the low proportion of the volume of the product as
O
~*~
compared with thc rcquired timber vo~ume, meaniny a low yicld.
Additional disadvantage of -the conventional neck is
the use of an iron or stainless steel reinforcing rod which is
dis~osed longitudinally thereof along tihe centerline in order to
prevent strains. This increases the overall weight of the ins-
trument.
It is an object of the invention to provide a neck for
a stringed instrument which can be manufactured in â facilitated
manner.
It is another object of the invention to provide a neck
for a stringed instrument which can be manufac-tured inexpensively
with a high yield.
I~ is a further object of the lnvention to provide a
neck for a stringed instrument which provides a high strength
without the use of a reinforcing rod.
It is still another object of the invention to provide
a process of manufacturing a neck for a stringed instrument which
enables products of uniform ~uality to be manufactured inexpen-
sively without requiring a special skill.
In accordance with the invention, there can be provided
a neck for a stringed instrument formed of a plywood comprising
a larnination of a plurality of sheets of bamboo. A length of
bamboo greater than the length of the neck to be produced and
llaving a proper diameter is radially stiffed into equal sectors
each having an arcuate section. Both the external and internal
surfaces of the sectors are sliced tangentially and the opposite
lateral edges of the sectors cut in a direction perpendicular to
the tangential direction, thus providing a plurality of sheets of
the required length which are rectangular in cross section. Using
any known wood lamination technique, the sheets are laminated into
a plywood. In a practical embodiment, the plywood is in the form
of a strai~ht square timber, the opposite ends of which are cut
~'~
~ ~ - 3
. . ~ . , ~ ,,,
s~
off, leaving the intermediate portion for use as a neck body.
The end portlons are used as a peg head and a mounting limb,
which are adhesively bondedwith the corresponding positions of the
neck
- 3a -
-,
. ~ ,, ~ , .
:`:
body portion in given orientations before cutting the plywood
into the neck form. Preferably, the major surface of the laminar
sheets is ali~ned in parallel relationship with the surface of
the neck body on which a finger board is mounted, or in a
direction perpendicular to the last mentioned surface.
In another embodiment of the invention, the peg head
portion and the nec]~ body may be formed by one piece plywood.
~efore laminating the sheets, the peg head portion of the sheets
~ may be folded to form a given angle with the neck body portionO
Alternatively, the peg head portion may be folded after the lamination
into the plywooa. These techniques can be advantageously employed
where the major surface of the sheets is parallel to the plane of
: the finger board.
~ A preferred bamboo material used in the invention is a
.. ~ .
species of bamboo commonly referred to as "MOHSCH" (phonetically)
in Japan and which is "phyllos-tachys mitis" by nomenclature.
. . .
i This species of bamboo may have a diameter up to 10 centimeters
or more and a thic]cness even exceeding 1 centimeter. The material
has a thin and dense fibre structure, and a high level of tough-
ness or resistance to crack while exhibiting a specific gravity
less than that of the conventional wood material for the neck.
What is more important, a stabilized strength and a strain-free
condition can be attained with this species of bamboo with a
seasoniny period which is substantially reduced than that of the
wood material, and this characteristic has been demonstrated in
::
its applications as rulers and slide rules. The drying period
from the fellin~ of bamboo until the sheets are prepared to the
lamination extends from several months to one year on the average
~here natural drying process is employed. ~lowever, a forced drying
process may be employed which ta~es place at 100C ~or 20 to 24
hours. A suitable sectional size of the sheets may be 5mm by 15
n~, for example.
- 4 ~
` ' , ' ' ' ~ " "'''~ ' ' ' ' ', ' . . ',', .~ ', "
:
Thus, the invention provides a neck which is reduced
in weigilt and still rigid enough to preven-t strains over a pro-
longed period of use. Also, tile invention provides a neck having
a minimized acoustic at-tenuation, substantially improving the
; acoustic effect.
The above and other objects, features and advantages
~ of the invention will become apparent from the following detailed
.~ description of an embodiment thereof with reference to the
drawings, in whieh:
Fig. 1 is a perspective view of the neck according to
the invention, also showing part of the sound box and the finger
board;
Fig. 2 is a cross section taken along the line 2-2 shown
in Fig. l;
' Fig. 3 is a cross section of a modification of the neek;
v Fig. 4 is a schematic section of bamboo, illustrating
.
the slittiny thereof; and
Fig. 5 is a sehematie illustration of the process of
; manufacturing tile neck according to the invention.
Referring to Fig. 1, the neck for a stringed instrument
according to the invention is generally shown by reference numeral
10. The neck 10 eomprises a straight elongate neck body 11, a
head 12 extending from one end of the nee]c body 11 and Eorm.ing
a given angle thereto, and a llmb 13 integrally extending from
the other end of the neck body 11. The limb 13 serves as the
mount to attach the neck 10 to a sound box 14. The nec]c body 11
i ineludes an arcuate bottom surface 18 and a flat upper surface
~ 17 (see Figs. 2 and 3) to which is adhesively bonded a finger
;;~ board 15 extending over the surface oE the sound box 14. The
head 12 is formed with a pair of slots 30 for receiving pegs of
known f orm, not shown.
In accordance with the invention, the neek 10 is formed
i~ _ 5 _
of a bamboo plywood. Referring to Figs 2 and 3, the plywood
comprises a multi-layer lamination of bamboo sheets 16 adhesively
secured together, tne sheets 16 in one layer being disposed in
complementary manner with respect to those in the adjacent layers. -~
In the example shown in Fig. 2, the shee-ts 16 are oriented so that
their major surface lies parellel to the upper surface 17 of the
neck body 11 to which the finger board 15 is applied, while in
the example of Fig. 3, they are oriented in a perpendicular dir~
ection thereto. While the neck having the sheet orientation
10 shown in Fig 3 has a greater resistance to bending stresses
applied as a result of the tension in the strings as compared
with the sheet orientation of Fig. 2, it is possible to achieve
a satisfactory strength for practical purposes with the arrange-
ment of Fig. 2.
Fig 4 illustrates the slitting of bamboo 20 into sectors
21. In the example, the bamboo 20 is shown as having a
cylindri.cal section and radially slitted into eight equal sectors
: ,
each having an arcuate cross section. Both the external and
internal surfaces of the sectors 21 are tangentially sliced to
form opposite flat surfaces, and the opposite lateral edges
cut in a direction perpendicular to the flat surfaces, thus
forming the sheets 16. A preferred species of bamboo is "phyllo-
stachys mitis" by nomenclature, which is called "MOHSOH"
(phonetically) in Japan. This species grows extensively,
principally in the southern part of Japan, and exhibits varying
properties dependin~ on the habitat. By experience, it is found
that this species of bamboo which grows in the northern district
of Shizuoka pre~ecture and the southern district of Yamanashi
prefecture of Japan is most suitable for the purpose of the
., .
invention. The bamboo may have a diameter and a thickness well
in excess of 10 and 1 centimeter, respectively, and thus bamboo
of any desired size may be chosen and splitted into a number of
- 6 -
<~ ,.~..,
:; , ,, "~
~ : , . ,:,
.:
~ S~
sectors which depends on ~he size. It is desirable that the
final sheets have a sectional size on the order of 5 mm by
15 mm, Eor example. It is preferable that the bamboo be
naturally dried for a period from six months to one year before
slitting it into the sectors. However, the bamboo may be slitted
and sliced into sheets before the completion of the full dry-
ing process, and the sheets subjected to a forced drying, which
may be effected at a -temperature of 100C for 20 to 24 hours in
the same manner as the usual wood drying techniques.
Fig. 5 illustrates the forma-tion of a neck from a
plywood 22 in the form of a straight square timber. The plywood
.
.~ 22 can be ~anufactured as a lamination of a number of sheets 16,
using the conventional wood lamination technique. Specifically,
~ an adhesive is applied to the individual sheets, whi.ch are then
` secured together under uniform pressure. ~ known synthetic resin
adhesive may be used. The opposite end portions 26, 27 are cut
.~ off the plywood along dotted lines 23, 24, leaving -the central
portion 25 which is to form the neck body 11. It will he noted
.~ that the dotted lines 23 extend angularly in accordance with the
predetermined angle to be formed between the peg head 12 and the
neck body 11 which the dotted lines 24 extend in a direction
perpendicular to the.length of the neck body portion 25. The
end portion 26 is adhesively bonded with the severed surface 2
of the portion 25 by inver-ting the portion 26 so that its
severed surface 31 is coplanar with the upper surface of the
neck body portion 25. Though not shown, the severed surface 31
of the portion 26 may be bonded with the lower surface of the
portion 25 so that the severed surface 2~ lies in coplanar re~
lationship with the upper surface of the peg head portion 26.
The other end portion 27 is adhesively bonded with the lower
surface of the portion 25 so that the severed surface 29 of
the end portion 27 is flush with the severed surface 32 of the
;
7 --
- . - : .. . ~ ., , ~ . :
2~
:. :
por-tion 25. In this manner, the approximate configuration of
the neck lO is achieved, and a finish machining to the final
~; neck form is then conducted.
-:~ The described process of manufacturing the neck is
".
equally applicable to either sheet orientation shown in Fig. 2
. or Fig. 3. ~owever, since the angle between the peg head 12
:,.
and the neck body ll is generally a relatively small value,
:~ the portion 26 need not be cut off the plywood 22 but the peg
:. head may be folded from the plane of the neck body portion 25 ` ~:
-,. 10 where the sheet orientation of Fig. 2 is employed.
~ Alternatively, with the sheet orientation of Fig. 2, prefolded
~ sheets may be used to provide the peg head 12 integral with
the neck body 11 and having the gi.ven angle witll respect to
the latter. In this case, it is only necessary to join the
limb 13 with the neck body ll.
. '
.. ~ .
.
.; ' ~',~
:' ~
3~ ::
' '
: - 8 ~
~ .
., , ~ , . ,~ ,
