Note: Descriptions are shown in the official language in which they were submitted.
BACKGRO~ND OF THE INVENTION
This inventlon relates to a vibratlon damper, and
more specifically to a vibration damper for the handle
or grip o~ a machlne, vehicle, or the llke which ls a
~ource of vibration, such as a chain saw or motorcycle.
The support for manual control o~ a chain saw, motor-
cycle, or other vlbratlon-generating body is usually
equipped with a cylindrical grip or the like for dlrect
manipulation by the operator. Consequently, vibratlons
~rom the source are immediately transmitted to the support
and the grip means, vlbrating the hand or hands of the user,
o~ten so serlously as to impalr his health. For example,
the vibrations of chain saws in cuttlng operations are
widel~ known to be responsible ror Reynaud's dlsease.
Attempts have heretofore been made to 180}ate the vlbra-
tions fro~. those ~aws, motorcycles, and other simllar
sources to protect the human body. However, there has been
no satisfactory solutlon proposed yet.
BRIEF SUMMARY OF THE INVENTION
It ls, therefore, an ob~ect of the presedh inventlon
to provlde a vibration damper for the handles or grips Or
chain saws, motorcycles, and other vlbration~generatln~
mechanlcal bodie~ thereby to protect the usèrs~agalnst
Reynaud's dlsease and other lnJurious e~fect~ upon health.
A more ~peci~lc ob~ect of the lnvention is to provlde
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a vlbration damper which comprises a spring assembly Or a
special construction through whlch a handle or grip is
~olned to a vlbratlonal mechanical body.
Wlth the vlbratlonal damper o~ the inventlon the
vibrations, to be otherwise transmitted rrom the mechanlcal
source to the user through the handle or g~ip, are sub-
stantlally damped or abs'orbed.
The above and further ob~ects and ~eatures of the
inventlon will be apparent ~rom the following detailed
escription taken in connection with the accompanying
drawlng. It is to be understood, however, that the
description of the invention as applied to the handle or
grlp Or a chaln aaw is for the purpos~e of illustratlon
only and is not intended as a definition Or the llmits of
the lnventlon.
BRIEF EXPLANATION OF THE DRAWINGS
FIG. 1 is a perspective view o~ a chaIn saw incorporat-
lng a vlbratlon damper according to the invention;
FIG. 2 is a sectional view of a vibration damper
embodying the inventlon;
PIG. 3 is a cross sectional view taken on the line
I of FIG. 2;
: FIG. 4 is a sectlonal vlew Or anothe~'vibration damper
:; ~ ., . ~ ~ ,
embodying the invention;
':: FIG. 5 is a cross sectlonal view taken on the llne
-- 2 --
:
~,
II-II Or FIG. 4;
FIG. 6 is a sectional vlew of another embodiment
Or the lnvention;
FIG. 7 is a cross sectional vlew taken on the line
III-III Or FIG, 6;
FIG. 8 is a sectional view Or another embodlment;
FIG. 9 is a cross sectional view taken on the llne
IV-IV Or FIG. 8;
FIG. 10 ls a sectlonal view Or still another embodl-
ment;
FIG. 11 ls a cross sectional vlew taken on the line
V-V of FIG. 1~; .
FIG. 12 is a sectional view Or yet another embodi-
ment;
FIG. 13 i8 a cross sectional view taken on the line
VI-VI of FIG. 12;
FIG. 14 i8 a sectional view Or a further embodlment;
FIG. 15 ls a cross sectional view taken on the llne
VII~ Or FIG. 14;
FIG. 16 ls a sectlonal vlew Or yet a ~urther embodi-
ment;
FIG. 17 is a cross sectlonal vlew taken on the llne
VIII-VIII o~ FIG. 16;
FIG. 18 is a sectional view Or still a further emaodl-
ment;
!
'.' .
FIG. 19 is a cross sectional view taken on the line
IX-IX of FIG. 18;
FIG. 20 ls a sectlonal vlew of an even further em~odl-
ment;
FIG. 21 is a cross sectional vlew taken on the line
X-X Or FIG. 20,
FIG. 22 ls a sectional vlew of an addltional embodi-
ment;
FIG, 23 ls a cross sectional view taken on the llne
~: XI-XI of FIG. 22;
FIG. 24 ls a sectional vlew o~ another embodlment;
; FIG. 25 ls a sectlonal view of the vl:bration damper
Or FIG. 24 in use;
FIG. 26 ls a sectlonal vlew o~ another embodlment;
FIG. 27 ls a sectlonal view o~ stlll another embodl-
. ment; and
.~ FIG. 28 is a sectional view Or a rurther additional
embodlment.c~ ..G. .,.
~ DETAILED DESCRIPTION OF THE INVENTION
.~ ~ Briefly stated, the vibratl~on damper accordlng to the
lnventlon.comprises a support, such as an arm, o~ a
vlbrational mechanicai body, a cylindri~cal grip or;:handle
provlded concentrlc~ally Wlth the~support~ànd a~d~apted to be
held by the hand o~ an operator ~or maDi~puiatlon? and a
coiled or splral spring havlng small and ~rge coiled
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~ .
~ .
.
portlons formed alternately, the sprlng belng disposedbetween the support and the grip. Each small colled portlon
is fixed to the support by weldlng or by sultable means
such as a groove or rldge formed on the support, and each
large colled portlon is engaged or contacted with the
cyllndrlcal grip or handle. This constructlon remarkably
lessens vibrations. If rubber or other reslllent material
is employed, for example, as part of the cylindrlcal grip,
the damper will attain a higher degree of vibration
dampin~ or absorption. The spring of the special configu-
rations as described above may comprise either a slngle
length with the alternate bulges and constrictlons or a
plurality of separate segmental or unit springs, each
consisting of at least one large coiled portion and at
least one small coiled portion. Also, the sprlng may be
secured to the grip and the support by welding, grooving,
bonding with adheslve, etc., or alternatively it may be
retained between the cylindrical grip and the support by
means of flanges formed at the both ends of the grip. As
a further alternative, an inner cylinder may be provided
instead of directly fixing the spring to the support or
havin~ lt engaged wlth the latter. In thls case, the erip,
inner cyllnder, and spring can be integrally assembled in
advance~
In FIG. 1 there ls shown'~ in perspective, a chain saw
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_ 5 -
adapted to lncorporate the vlbration damper of the invention.
The numeral 1 designates a houslng accommodatlng the
drives, hereinafter called the vibrational body because it
con~tltutes a source Or vibratlons. The saw blade ln the
~orm of an endless chain is indicated at 28. The vibrational
body 1 includes a support 2, such as an arm, to be gripped
by the operator. A grlp or handle 3 ls sleeved over an
upper portion of the support 2. The vibration damper
accordlng to the lnvention pertains to a structure ~oining
the support 2 and the grip 3 together. Thls applies to all
of the embodlments now to be descrlbed in detail.
Referrlng now to FIGS. 2 and 3, one embodlmènt of the
inventlon 1~ illustrated. Throughout the~e and all other
ensulng figures similar reference numerals lndicate slmilar
members or portions. On a tubular support 2, such as an
arm~ o~ a vibrat~lbody ls fitted a spring cons~isting o~
a row of barrel-shaped sprlng unlts 4, held in place by
weldlng or other connecting means, such as grooves and
stopper ridges formed on the support. This sprlng comprises
an axial row of barrel-shaped unlts as shown, each unlt
s~tarting wlth a neck or constrlctlon, bulging mldways, and
agaln~narrowing down to form the startlng port~o~or the
next-unlt in a cycllc arrangement. The enve ~ of the
spring has slnusoidal or deformed s~ usoldal contours.
Since~the sprlng has a plurallty Or constrlctions Or the
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same diameter, it can be directly secured to the support
wlthout the aid Or other ~oining means. 0~ the other hand,
the plurality of bulges of the same d~ameter may be fixed
to the inner surface of an lnner cylinder 5' of metal, which
in turn is fitted to the inner surface of the grip 3. In
this way the spring comprising the barrel-shaped spring
units 4 of alternate bulges and constrlctions permits the
grip to be fixedly mounted on the support to effect vibratlon
damplng. The inner cylinder 5' of metal is fitted ln, or
covered wlth, an outer sleeve 5 of vulcanized rubber or
other resllient material, the both comblnedly constltuting
the ~ylindrical grip 3. The outer sleeve 5 is formed wlth
flanges 71~ 72 at the both ends for contact with the both
extremltles 61, 62 f the spring to keep the latter from
moving axlally. Thus lt has some ~ibration damplng or
absorblng action, pro~ides adequate frictlon for gripping,
and prevents removal of the spring by means of the flanges
71~ 72. Where desired, the spring may be cut off at given
points of either the constrlcted or bulged portions into
separate segmental springs.
FIGS. 4 and 5 show another embodiment of the vlbration
, ,~
damper accordlng to the invention.~ Here, the ~pring is
likewi~e secured to the support 2 and ls 8 ~ in
``~ structure to that of the embodlment lllu~trated ln FIGS.
2 and 3 except that lt end~ at 61, 62 wlth bul~es lnsteaù.
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Also, the grip 3 in this embodiment is made of a single
metal cylinder, whlch ls bent at ends perpendicularly to
the axls to form annular flanges 71 " 72' for restrlctive
engagement with the bulged ends 61, 62 of the spring. The
grip 3 ln the form of a sleeve restrlcts the axial move-
ment of the spring and prevents it from slipping off.
Another embodiment Or the invention is shown in
FIGS. 6 and 7. Unlike the preceding embodiments, it has
an inner metal cylinder 8 dlsposed between the tubular
support 2 and the coiled spring having alternate constric-
tions and bulges and simllarly flxed to the support. The
both ends of the inner cylinder are bent up at right
angles to the axi~ to hold the opposite ends 61, 62 f
constrictions of the spring unremovably. An outer metal
cylinder 8', which ~orms the cyllndrlcal grlp 3, is
flangeless and is secured by welding or the like to the
bulges of the spring. Thls embodiment is easy to manu-
facture, because the lnner and outer cyllnders 8, 8' and
the spring in a row of barrel-shaped units can be assembled
beforehand and flxed as such to the support 2 to complete
the necessary mounting work.
FIGS. 8 and 9 show still another vlbration damper
embodylng the inve~tion. Here an inner metal cyllnder 10
ha~ upright flanges 131, 132 engaged wlth constricted ends
61, 62 f a sprin~ to hold the latter unmovably. In
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additlon, the metal cylinde~ has cylindrical extenslons
lll, 112 flxed to the support 2 by cap screws 12l, 122,
respectlvely. An outer cyllnder lO', constltuting the grip,
ls formed of resilient materlal, such as hard rubber, to
provide a burfer and an adequate friction for the hand of
the operator.
In FIGS. 10 and ll ls shown an embodiment slmilar
to the one shown ln FIGS. 8 and 9. The only dlfference ls
that the grlp 3 Or thls embodiment conslsts of a rubber
cylinder lO' and a metal cyllnder 14 fltted inslde as a
lining, to whlch the sprlng is secured. In thls case the
rubber material may be sorter than the counterpart in
FIGS. 8 and 9.
Another embodiment is shown in FIGS. 12 and 13. Llke
all Or the precedlng embodlments lt has a coiled sprlng 4
wlth lts constrlctions secured by sultable means to the
tubular support 2. The bulges of the spring are banded
to the lnner surface of the grlp 3 made of hard rubber or
other resllient material. The both ends of the grip 3 are
rormed with flanges 71~ 72. A digtinct feature Or this
embodlment ls a plurallty Or nonslip,~ ringlike lands
~ormed on the outer perlphery or~t~e grip 3. The lands
. . . ~. . .
enable the operator~to take a~rirmer grip, with some damp- -
lng effect in addit-ion to the vibratlon-lsolating erfect of
the c~dsprlng.
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i~43~90
A simllar embodiment of the invention ls given in
~I¢S. 14 and 15. Its grip 3 consi~ts Or a hard rubber
cyllnder having end flanges 71~ 72 and also a plurality o~
nonslip lands 15' of sponge rubber provided on the outer
perlphery Or the rubber cylinder. This structure ls more
ef~ectlve in lessenlng the transmis~lon of vlbration~.
FIGS. 16 and 17 illustrate another embodlment, in
which the spring is divlded in~o separate barrel-shaped
segments 4, each having a constriction and a bulge and
fixed to the tubular support 2. The grlp ls concentrically
,
mounted on the spring. As shown~j t~e~gri~p~-3 1s~ a cylinder
o~ hard rubber havlng a plural$ty of rlngllke ti~rening
-rlbs 16 formed on lts inner su~faoe.~.In-rlnglikc recesses
16' rormed by the rlbs, the bulges oP the~sprlng~segments
~, are fltted ~ecurely ln place. -~
In a further embodlment o~-bhé invent~on;shown in
!i,~,;' ~ ' FIGS. 18 and 19, a pair of splral springs 4 are fl~ed to
~ the tubular support 2, spaced apart at two points along,
~ .
.
~- and in planes at rlght angles to, the axls Or the support,
by sultable means. Around thQse sprlngs ls fltted a grip
3, eonsisting Or a~metaI cyli~ ~ 5'~and~ an: ou~er cylinder
5 of rubb~er or other resl~lie ~ at~erla;l~ ~ta ~ d-~t~o the
;c~llnder and ha~lng~rlanges ~ 7z ~orme~ ~r ~ oslte ends.
Although the springs are co~rled to conrl-~ratlons unllke
those ln the embodiments~so far described, they~achieve
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the same vibration damping effect as by the preceding
ones.
Yet a further embodiment i8 shown ln FIGS. 20 and 21.
The sprlngs 4 are slmilar to those ln FIGS. 18 and 19 but,
ln order to retain them in the space between the support
2.nand the m~tal cylinder 5', the support ls formed with
annular grooves 20 on the outer periphery and the metal
cylinder is formed with corresponding annular grooves 21
on the inner surface, so that the both ends 18, 19 Or each
spring are fitted in each set of those grooves. In this
way the damping portions and the grip are positively
secured in position.
An even further embodiment of the invention, shown in
FIGS. 22 and 23, uses spiral sprlngs 4 coiled in the same
way as those in FIGS. 18-21 but are made o~ narrow, flat
bands
X~X instead o~ round wires.
FIGS. 24 and 25 illustrate another embodlment, in
which the spring 4 has a plurality of barrel-shaped unlts
with alternate constrictions and bulges of given diameters.
The constrictions are fixed to the tubular support 2.
~oncentrically with the support, an elongate, barrel-shaped
grip 3 i9 mounted thereon. It consists Or a rubber
cylinder havlng hollow sections 22 varied stepwise in
diameter and a complementary, reinforclng metal cylinder
23 of corresponding configurations fitted tight in the
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~1~3390
-rubber cylinder. Thus the lnside dlameter Or the metal
cylinder 23 increases, sectlon after sectlon, from the
bvth end~ toward the middle portion. As lndicated, only
the bulges Or the barrels near the both endæ of the sprlng
4 are fixed to the metal cylinder 23. Therefore, while
the magnitude of motlon or vibratlon from a machlne or
the like as the source ls small, the end spring sectlons
wlll absorb lt. As the magnltude lncreases, the other
spring sections will, one after another, take part in the
vlbratlon damping as shown, for example, in FIG. 25. The
advantages of this embodlment are the comfort with which
the operator can grlp the damper and the smooth increase
or decrease of vlbratlon damplng ln proportion to changes ;
in the magnltude of vibratory motion.
FIG. 26 shows yet another embodlment Or the inventlon.
This vlbratlon damper includes a coiled sprlng 4 ln a row
of barrel-shaped unitæ provided around the tubular support
2. The spring is covered by a grip 3 consisting of a
stralght outer cylinder 5 of rubber formed with flanges
71~ 72~ and ~e~ata~Jcylinder-5' fitted as a linlng for
relnforcement. The bulges o~ the ~ring barrels are
progresslvely reduoed ln diameter from the both ends
toward the middle portlon~o~ the sprt~g~ Co~sequently,
the damper functlons ln use in the~same manner as that of
FIGS. 24 and 25.
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1143390
FIG. 27 shows another embodiment as a modlfication
Or that which is lllustrated in FIGS. 18 and 19. Similarly,
the spiral springs 4 in a palr are located innthe same
planes normal to the axis of the support 2, but thls
arrangement dlffers from the prevlous one in th~t the
lnner and outer ends of each spring are coiled double to
ensure posltive fixing to the support 2 and the reinforc-
ing metal cylinder 5'.
A further additional embodiment shown in FIG. 28
utilizes the splral springs of FIGS. 18 and 19 but retain
them in a different way. Tne support 2 is rormed wlth two
annular grooves ln spaced relatlon, collars 271, 272 are
fitted in the grooves, and the vibration-damping unit
sprlngs are kept in pressure contact with the inner sldes
of the collars facing each other. On the other hand, the
grip 3 conslsts of a small-diameter, re$nforclng~metal-
cyllnder 24 having large-diameter, flared ends 261, 262,
and a rubber cyllnder 25 snugly fltted in the thus-recessed
outer periphery of the metal cylinder. Each unit spring
is engaged on one side with the annular step deflned by
the flared end of-the metaI cylinder. These steps coact
with the collars to retain the springs- unremovably in place.
.
~ 13
;
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