Note: Descriptions are shown in the official language in which they were submitted.
1093C)38
'l'he present invention relates to a shock absorb-
ing device and particularly to an apparatus for damping
large forces within a short distance and dissipating
large amounts of kinetic energy within a short time.
More specifically, the present invention is concerned
with a shock absorbing device suitable for various parts
or portions of a motor vehicle for minimizing damage on
the vehicle due to collision, and thereby ensuring safety
of the driver and or passengers of the vehicle.
In case of collision of the motor vehicle with an
obstacle, there exists a great danger to the vehicle
passengers by the impact force causing the driver to be
thrown forwardly against the steering wheel and also
causing the passengers against some interior parts of
the vehicle~ Thus, it is desirable to provide impact
absorbing means to parts and/or portions of the vehicle
so as to eliminate or at least mitigate such danger.
Up to now, there have been proposed a number of
shock absorbing devices which a~e used for the various
parts and portions of the motor vehicle, such as for a
bumper mechanism, a seat belt system, a steering system,
a knee protecting system and a head protecting system in
; an instrument panel.
However, each of these shock absorbing devices has
not been widely used for the parts and/or portions of
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the véhicle by reason of -~heir complicated construc-tions. More
spec.i.fically speaking, one shock absorbing devicc which is
dcsi~.~ned t-o he 5Ui. ~able for an impact ahsorbing s~eering system
.is no1 1~secl i.n a safe~y seat bclt sys1-cm. ~ach of l-hese devi.ces
h;ns }.)eerl l~rocluced or manufactured so as ~o specifical]y suit
t,he on].y one pu:rpose thereof. This causes a high cost of 1he
safcty system.
Therefore, it is a mai.n object of the present invent;,on
to provide an improved shock absorbing device which can be widely
used in various kinds of safety systems of a motor vehicle.
It is another object of the present invention to provide
a multi~purpose shock absorbing device whi,ch can be produced
economically and is simple in construction.
It is still another object of the present invent.ion
to provi.de a saf~y ,seat hclt system which ha~ t,he.rein an
improved shock absorbing device.
It is a further object of the present invention to
provide an impact absorbing steering system equipped with an
improved shock absorbing device.
According to the present invention there is provided
,a safety seat belt system for protecting a passenger of a motor
vehicle during rapid deceleration of the vehicle, comprising:
a seat belt proper for embracing the passenger; a strap member
, connected at its one end to one end of said seat belt proper,
said strap member being made of plastically deformable material;
the width of the strap member being gradually decreased from
the one end thereof, to which the seat belt proper is connected,
toward a free end thereof; and a flat base member formed therein
with a plurality of parallelly arranged elongate slots, every
adjacent two ofwhich define therebetweena respectivebridge portion,the
fl.at base member being tightly but swingably connected at one
end thereof to a relatively stationary portion of said vehicle,
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said sl,rap mem}ier being interlaced thro~gh said elongate slots
of sai.d base mernber so that when an impact shock j.s applied to
.said .~3eat be],t proper by a passenger upon rapid deceleration,
~e ;1 rap Inernber :i.S .successi,vely p1.asti,cally deformed as it is
~'o~:ced to sli,de bel-wecn and ovcr said respective bri~ye portions.
'l'he invention will now be dcscribed in more detail,
by way of c~amp]e only, with reference to the accompanying
drawinys, in which:
Fig. 1 shows several embodiments of a shock absorbing
device according to the present invention, each schematically
illustrating the novel concept of the present invention;
Fig. 2 is a schematically illustrated plan view of
a safety seat belt system incorporating the shock absorbing
dev,ice of the present invention;
Fig. 3 is a sect:.ional view taken along the line
I-I of Fig. 2;
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Fig. 4 is a s~hematically illustrative perspective
view of an impact absorbing steering system incorporating the
shock ahsorb;ng dcv;ce of the prcsent invention; and
Fiy. 5 is a longitudinally sectioncd view of the
illul;~ration of Fiy. 4.
~eferring now to Fig. 1 of the drawings, there are
il]ustrated five variations a to e of a shock absorbing device
_ of the present invention. Each of the variations a to e
generally comprises a first or base member 12 which is fixed to
a relatively stationary member or portion, though not shown.
At least two elongate or rod members 14 are firmly fixed to the
base member 12 while beiny spaced apart from and in parallel to
each other as shown. Alternately passing over or interlaced
hetween the rod members 14 is a strap member 16 which is made of
pJastically deform~ble material. The strap rncmber 16 has one end
16a loose and the other end 16b connected to a relatively movable
member 18.
With the above-stated construction, the shock absorbing
device _ will operate as follows:
When an impact force is applied to the relatively
movable member 18 from the direction indicated by the arrow A,
the plastically deformable s~rap member 16 is driven away from
the base men~er 12. During the movement,
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the strap member 16 will be successively plastically
deformed at its contacting portions with the rod
member ].4. The successive plastical de~ormations of
the strap member 16 will absorb or weaken the impact
shock. In reality, an elastic deformation of the
strap member 16 will occur and a frictional resistance
will form between the contacting surfaces of the strap
member 16 and the rod members 14 during the movement
of the strap member 16. Fortunately, the elastic
deformation and frictional resistance are useful, but
at a low rate, for absorbing the shock.
As stated above, the shock absorbing device 10 has
a very simple construction, thus, it is very easy to
control the shock absorbing capability of it. In con-
nection with the determination of the shock absorbing
capability of the subject device 10, there exist fol-
lowing several parameters:
1) cross sectional form of the rod member 14;
2) cross sectional area of the rod member 14;
. 20 3) number of the rod members 14;
4) surface roughness of the rod member 14 and that
. of the strap member 16;
5) thickness and width of the strap member 16;
6) distance between the rod members 14;
7) mutual arrangement of the rod members 14 and
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~he strap Inember 16; and
8) l)hysical property of ~he strap member 16. By
choos:irlc3 one or more of t,he parameters 1 -to 8, various shock
sor~iny de~vices having various shock a~sorbing capabilities
respect,ively wi],l be readily Inade without emp]oying any other
speci,fically desic;nated members.
Fi~s. 2 and 3 show an exemplary application of the
subject shock absorbing device 10 to a safety seat belt system
17 of the motor vehic]e. In this figure, one end of a seat
belt proper and a D-ring fastened to the end of the seat belt
are respectively designated by reference numerals 20 and 22. A
strap 24 which is made of plastically deformable material and acts
as the strap member 16 of Fig. 1 is connected at its one end
to the D-ring 22 by means of a fastener 26. The width of the
strap 24 is ~radually deoreased in the direction from one end
thereof, to which the D-ring 22 is connected, to a free end
thereof. As well shown in Fig. 3, the strap 24 is interlaced
through parallel slots 28 formed in a base 30 which acts as the
first or base member of Fig. 1. Bridges 32 located between the
neighbouring two slots 28 act as the rod members 14 in the case
of Fig. 1. The base 30 is tightly but swingably connected through
a bolt 34 to a relatively stationary member such as the vehicle
floor (not shown).
With this construction of the saiety seat belt
I
, 30
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system 17, the impact shock applied to the seat belt
proper 20, by a passenger, upon a vehicle collision i5
absorbed or at least weakened by the shock absorbing
device 10.
Figs. 4 and 5 show another exemplary application
of the subject shock absorbing device 10 to a safety
steering system 36. The safety steering system 36 in
which the subject shock absorbing device 10 is used com-
prises a hollow outer housing 38 which is firmly fixed
to the vehicle body by means of a bracket 40. Tele-
scopically received within the housing 38 is a tubular
inner shaft 42 which consists of a large diameter
portion 43 and a small diameter portion 44 as shown.
First and second ball bearings 46 and 48 are engaged
between the inner shaft 42 and the outer housing 38 at
the large and small diameter portions 43 and 44 re-
spectively, thus allowing the tubular inner shaft 42
to rotate with respect to the outer housing 38. Along
the inner cylindrical surface of the small diameter
portion is formed a suitable number of longitudinally
extending grooves (not shown). The end of the large
diameter portion 43 of the inner shaft 42 is suitably
coupled through a steering linkage 50 to the front
wheels (not shown) of the vehicle. Within the small
diameter portion 44 of the inner shaft 42 is disposed
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an end or head portion 52 of a stub shaft 54 which is
connected at its other end portion to a steering wheel
56 shown in phantom in Fig. 5, so that the vehicle may
be steered by turning the steering wheel 56. The head
portion 52 is formed at its cylindrical surface with a
suitable number of longitudinally extending projections
~not shown) which will be engaged with the grooves of
the small diameter portion 44 of the inner shaft 42 for
thus allowing the head portion 52 and accordingly the
stub shaft 54 to longitudinally move with respect to
the inner shaft 42. A box shaped cover 58 having a
square eross section portion 60 and a eylindrical
portion 62 is 8paeedly mounted around the stub shaft
54 so that the portion 60 eovers the outside of the
outer housing 38. A braeket 64 whieh is made of plastie
is used for conneeting the eover 58 to the body of the
vehicle. The reason why such plastic bracket is employed
in this case will beeome clear later. Between the stub
shaft 54 and the cylindrical portion 62 of the box
shaped eover 58 is engaged a third ball bearing 66
which has inner and outer raees ~no numerals) firmly
eonneeted to the stub shaft 54 and the cover 58, re-
speetively. Preferably, the eonneetions between the
third ball bearing 66 and the stub shaft 54, and between
;~25 the third ball bearing 66 and the tubular eover 58 may
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be made by welding. For the purpose of obtaining a
balanced operation of the shock absorbing device 10,
the safety steering system 36 in this case is equipped
with two shock absorbing devices 10. Each of the
devices 10 is arranged between the square cross section
portion 60 of the cover 58 and the outside portion of
the outer casing 38 and comprises elongate or rod
members 68 which are spaced from each other and firmly
connected at their both ends to the outer housing 38,
and a strap 70 which alternately passed through the
clearances defined between the rod members 68 and is
firmly fastened at its one end to the tubular cover 58.
In a collision of the vehicle, the impact shock
applied to the steering wheel 56 by the vehicle driver
cause8 destruction of the plastic bracket 64. Then,
the plastically deformable straps 70 are driven away
from the rod members 68 connected to the outer housing
38 due to the forward movement of the cover 58. During
the forward movement of the straps 70, the straps are
saccessively plastically deformed in a manner mentioned
before, so as to absorb the impact shock. Consequently,
the vehicle driver is safe under such collision.
Although, in the previous description, only one
~ : strap is passed over the rod members in each of the
`; 25 shock absorbing devices, it is also possible to use
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a piled strap member consisting of at least two straps
ovcrlapping each other for each of the devices. In this
case, there will also be generated sliding friction at
the contacting surfaces of the two straps during the
extracting movement of the strap member from the rod
members. This sliding friction is also useful for
damping the impact shock.
