U.S. patent application number 10/598821 was filed with the patent office on 2008-03-27 for strap tension indication.
This patent application is currently assigned to BRITAX ROMER KINDERSICHERHEIT GMBH. Invention is credited to Hermann Wetter.
Application Number | 20080072404 10/598821 |
Document ID | / |
Family ID | 34963040 |
Filed Date | 2008-03-27 |
United States Patent
Application |
20080072404 |
Kind Code |
A1 |
Wetter; Hermann |
March 27, 2008 |
Strap Tension Indication
Abstract
A safety harness webbing strap (1) has a piece of elastomeric
belt (2) stitched (3) to it at two points along its length. The
position of the two stitching along the length of the strap is such
that in the relaxed state of the strap, with not tension in either
the strap or the belt, the later draws a bight or belly (4) into
the strap. Two lengths (5,6) of sleeving are stitched into the same
points (3). The elastomeric belt is threaded within the lengths of
sleeving. These are of equal length and jointly extend for the full
length of the elastomeric belt in its relaxed state. when the
elastomeric belt is tensioned, it opens at the joint between the
two lengths (5,6) and stretches to a length greater than the
sleeving. Thus it becomes exposed to view between the lengths of
sleeving, as shown in FIG. 2. The extent of stretching of the belt
is limited by the distance along the strap between the stitching.
Once the strap is straightened, the belt will stretch no more.
Inventors: |
Wetter; Hermann; (Ulm,
DE) |
Correspondence
Address: |
ADAMS INTELLECTUAL PROPERTY LAW, P.A.
Suite 2350 Charlotte Plaza, 201 South College Street
CHARLOTTE
NC
28244
US
|
Assignee: |
BRITAX ROMER KINDERSICHERHEIT
GMBH
Ulm
DE
|
Family ID: |
34963040 |
Appl. No.: |
10/598821 |
Filed: |
March 7, 2005 |
PCT Filed: |
March 7, 2005 |
PCT NO: |
PCT/IB05/00460 |
371 Date: |
July 10, 2007 |
Current U.S.
Class: |
24/68R |
Current CPC
Class: |
B60R 2022/4866 20130101;
B60R 22/48 20130101; B60R 22/105 20130101; B60R 22/12 20130101;
B60R 2022/4841 20130101; Y10T 24/21 20150115 |
Class at
Publication: |
24/68.R |
International
Class: |
A44B 11/25 20060101
A44B011/25 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 12, 2004 |
GB |
0405550.5 |
May 11, 2004 |
GB |
0410457.6 |
Claims
1. A tension indicator in combination with a strap whose tension is
to indicated, the combination comprising: (a) the strap and (b) a
tension indicator, the tension indicator comprising: a resilient
member attached at its ends to two points along the length of the
strap, the points of attachment being further apart in the
longitudinal direction of the strap than the free, non-tensioned,
length of the resilient member between its ends, whereby when the
strap is slack the resilient member draws a bight in it between the
attachment points and (c) means for visually indicating elongation
of the resilient member when the strap and the resilient member are
stretched in tension, whereby absence of slack in the strap can be
noted.
2. A tension indicator and strap combination as claimed in claim 1,
wherein the attached ends of the resilient member are terminal ends
thereof.
3. A tension indicator and strap combination as claimed in claim 1,
wherein the attached ends of the resilient member are effective
ends spaced from terminal ends by vestigial piece.
4. A tension indicator and strap combination as claimed in claim 1,
wherein the attached ends are attached directly to the strap.
5. A tension indicator and strap combination as claimed in claim 1,
wherein the attached ends are attached to the strap via
intermediate members.
6. A tension indicator and strap combination as claimed in claim 5,
wherein the intermediate members form part of the visual indicating
means.
7. A tension indicator and strap combination as claimed in claim 1,
wherein one of the resilient member and the visual indicating means
is an inner member at least partially within the other as an outer
member.
8. A tension indicator and strap combination as claimed in claim 7,
wherein: (a) the resilient member is an inner member and (b) the
indicating means is: an outer member attached at its ends to the
ends of the resilient member and encasing the resilient inner
member, the outer member being provided with at least one opening
arranged to open on stretching of the outer member to expose the
inner resilient member to view; (c) the arrangement being such that
with both members having their ends attached to each other and the
strap, both the outer and the inner members stretch in use.
9. A tension indicator and strap combination as claimed in claim 7,
wherein: (a) the resilient member is a length of resilient material
attached at two points along the length of the strap, the points of
attachment being further apart in the longitudinal direction of the
strap than the free, non-tensioned, length of the resilient
material; and (b) the visual indicating means is a sleeve attached
to the strap with the resilient material being accommodated within
the sleeve, the sleeve being of a length to cover the resilient
material when it is not tensioned; (c) the arrangement being such
that on tensioning of the strap, the resilient material is drawn
from the sleeve being exposed to view indicates that the strap is
tensioned.
10. A tension indicator and strap combination as claimed in claim
9, wherein the sleeve is attached to the strap remote from the end
of the resilient material.
11. A tension indicator and strap combination as claimed in claim
9, wherein the resilient material is attached to the strap via the
sleeve.
12. A tension indicator and strap combination as claimed in claim
9, wherein the sleeve is provided at one end of the resilient
material, exposing resilient material at the other end on
stretching.
13. A tension indicator and strap combination as claimed in claim
9, wherein the sleeve is provided at one both ends of the resilient
material, exposing resilient material in the middle on
stretching.
14. A tension indicator and strap combination as claimed in claim
9, wherein the resilient material is self-coloured.
15. A tension indicator and strap combination as claimed in claim
9, wherein the resilient material is provided with gradations of
colour or a marker, to indicate the degree of tension in the strap
according to the extent of exposure.
16. A tension indicator and strap combination as claimed in claim
4, wherein: (a) the resilient member is an outer member having a
central void and (b) the indicating means includes: (i) at least
one opening in the resilient outer member and arranged to open on
stretching of the outer member and (ii) an inner member provided in
the void inside the resilient outer member, the inner member being
visible through the or each opening when the outer member is in its
stretched state.
17. A tension indicator and strap combination as claimed in claim
16, wherein the inner member is an extensible member having its
ends attached to the strap, preferably at the ends of the outer
member.
18. A tension indicator and strap combination as claimed in claim
16, wherein the inner member is an inextensible member attached to
the strap, preferably at one of its ends to one of the ends of the
outer member.
19. A tension indicator and strap combination as claimed in claim
16, wherein the inner member is captivated within the outer member
by the outer member alone.
20. A tension indicator and strap combination as claimed in claim
16, wherein the resilient member is a coil spring, attached to the
strap by end eyes, and teh indicating member is a peg or rod within
the spring.
21. A tension indicator and strap combination as claimed in claim
19, wherein the coil spring is of the type which is coil bound when
under no tension, thereby obscuring the indicating member until
tensioned sufficiently to open the coils of the spring.
22. A device to indicate tension in strap, the device comprising:
(a) the strap; and (b) a resilient member attached at its ends to
two points along the length of the strap whereby when the strap is
slack the resilient member draws a belly in the strap between the
attachment points, the length of the resilient member and the
separation in the strap of the attachment points being chosen to
ensure that the belt is fully stretched when tension of a desired
level has been reached and teh desired level of tension being
indicated by the belt being exposed and the belly being pulled out
of the strap.
23. A safety strap intended to be tensioned in use to a
predetermined extent; the strap bearing a resilient member attached
thereto at first and second positions spaced apart along its
length; the resilience of said resilient member and the spacing of
said first and second positions being configured to permit the
strap and the resilient member to lie adjacent one another when the
strap is tensioned to said predetermined extent and to cause the
strap to loop away from the resilient member, between said
positions, when it is tensioned to a lesser extent; thereby to
provide a visual indication of the tension applied to the strap.
Description
[0001] The present invention relates to a device for indicating
strap tension.
[0002] In an automotive child restraint system, typically a child
safety seat attached to the adult seat of a car, there is a
requirement to tension the straps holding the child into the child
seat and/or the strap(s) tethering the child seat in the vehicle.
For the former straps, normally this is done by drawing out a
central strap, which is attached to and tensions the individual
straps, particularly the shoulder straps. In the latter case,
tensioning is likely to be by tightening of the strap with a
conventional strap adjuster.
[0003] Conventional tensioning arrangements have no means by which
the user can gauge the tension in the straps, aside from feeling
them.
[0004] In this specification, the term "tension indicator" is used
to mean a device to indicate absence of slack.
[0005] The object of the present invention is to provide an
indicator for indicating tension in a restraint strap.
[0006] According to the invention, there is provided a tension
indicator in combination with a strap whose tension is to be
indicated, the combination comprising: [0007] the strap and [0008]
a tension indicator, the tension indicator comprising: [0009] a
resilient member attached at its ends to two points along the
length of the strap, the points of attachment being further apart
in the longitudinal direction of the strap than the free,
non-tensioned, length of the resilient member between its ends,
whereby when the strap is slack the resilient member draws a bight
in it between the attachment points and [0010] means for visually
indicating elongation of the resilient member when the strap and
the resilient member are stretched in tension, whereby absence of
slack in the strap can be noted.
[0011] It should be understood that by the "ends" of the resilient
member is intended not necessarily its terminal ends, but its
effective ends in that they represent the points of attachment and
transfer of tensile force to the resilient member in use. For
instance, in one embodiment, where the resilient member is a length
of elastomeric belt stitched to the strap, vestigial pieces between
the stitching and the terminal ends perform no part in the
stretching of the resilient member to indicate tension in the
strap.
[0012] The sleeve can be attached to the strap remote from the end
of the resilient material. For instance, the resilient material may
be attached to the strap via the sleeve. However, the sleeve and
the resilient member are preferably stitched together by the same
stitching to the strap.
[0013] Thus in one preferred embodiment: [0014] the resilient
member is an inner member and [0015] the indicating means is:
[0016] an outer member attached at its ends to the ends of the
resilient member and encasing the resilient inner member, the outer
member being provided with [0017] at least one opening arranged to
open on stretching of the outer member to expose the inner
resilient member to view the arrangement being such that with both
members having their ends attached to each other and the strap,
both the outer and the inner members stretch in use.
[0018] In particular: [0019] the resilient member is a length of
resilient material attached at two points along the length of the
strap, the points of attachment being further apart in the
longitudinal direction of the strap than the free, non-tensioned,
length of the resilient material; and [0020] the visual indicating
means is a sleeve attached to the strap with the resilient material
being accommodated within the sleeve, the sleeve being of a length
to cover the resilient material when it is not tensioned; the
arrangement being such that on tensioning of the strap, the
resilient material is drawn from the sleeve and being exposed to
view indicates that the strap is tensioned.
[0021] The sleeve can be provided at either end of the resilient
material, or indeed at both ends. If it is attached at one end, it
will expose the resilient material at the other end. If it is
attached at both ends, the exposure is in the middle.
[0022] In another embodiment: [0023] the resilient member is an
outer member having a central void and [0024] the indicating means
includes: [0025] at least one opening in the resilient outer member
and arranged to open on stretching of the outer member and [0026]
an inner member provided in the void inside the resilient out
member, the inner member being visible through the or each opening
when the outer member is in its stretched state.
[0027] In one alternative, the inner member is an extensible member
having its ends attached to the strap, preferably at the ends of
the outer member. Alternatively, the inner member is an
inextensible member attached to the strap, preferably at one of its
ends to one of the ends of the outer member. Again, the inner
member can be captivated within the outer member by the outer
member alone.
[0028] Preferably, the resilient member is a coil spring, attached
to the strap by end eyes, and the indicating member is a peg or rod
within the spring. The coil spring can be of the type which is coil
bound when under no tension, thereby obscuring the indicating
member until tensioned sufficiently to open the coils of the
spring.
[0029] To help understanding of the invention, two specific
embodiments thereof will now be described by way of example and
with reference to the accompanying drawings, in which:
[0030] FIG. 1 is a perspective view of a tension indicator and a
strap in accordance with the invention in a relaxed state;
[0031] FIG. 2 is a similar view of the indicator in a tensioned
state;
[0032] FIG. 3 is a view similar to FIG. 1 of a second tension
indicator and strap of the invention; and
[0033] FIG. 4 is a view similar to FIG. 2 of the second tension
indicator.
[0034] Referring first to FIGS. 1 & 2 of the drawings, a
webbing strap 1 of the type used in a safety harness, e.g. for
strapping a child into a safety seat or for tethering a safety seat
in a vehicle, has a piece of elastomeric belt 2 stitched 3 to it at
two points along its length. The position of the two stitchings
along the length of the strap is such that in the relaxed state of
the strap, with not tension in either the strap or the belt, the
later draws a bight or belly 4 into the strap.
[0035] Two lengths 5,6 of sleeving are stitched into the same
points 3. The elastomeric belt is threaded within the lengths of
sleeving. These are of equal length and jointly extend for the full
length of the elastomeric belt in its relaxed state. The sleeving
being of a type which does not readily crumple, such as filled and
calendered non-woven material, it completely encloses the
elastomeric belt when relaxed as shown in FIG. 1.
[0036] When the elastomeric belt is tensioned, it opens at the
joint between the two lengths 5,6 and stretches to a length greater
than the sleeving. Thus it becomes exposed to view between the
lengths of sleeving, as shown in FIG. 2. The extend of stretching
of the belt is limited by the distance along the strap between the
stitching. Once the strap is straightened, the belt will stretch no
more.
[0037] The actual tension in the strap, when the belt is fully
stretched will be that in belt or more if the strap is carrying
tension in parallel to the belt.
[0038] The length of the belt and the separation in the strap of
the stitching will be chosen to ensure that the belt is fully
stretched when the tension has reached the desired level.
[0039] This desired level can be indicated simply by the belt being
exposed and the belly being pulled out of the strap.
[0040] Alternatively, belt can be coloured, whereby the exposed
portion is red R for instance when insufficient tension is present,
but the length of red colour is limited whereby when the belt is
fully tensioned green portions G are exposed on either side of the
red portion.
[0041] In another alternative, the elastomeric belt can be replaced
by a piece of shock cord or indeed a coil spring as the length of
resilient material or resilient member.
[0042] Referring now to FIGS. 3 and 4, the tension indicator there
shown comprises a coil spring 11 of the type that is coil bound, as
shown in FIG. 3, when carrying no tension. It has eyes 12 at its
ends, by which it is stitched 14 to a strap 15. Loose inside the
spring, and invisible in FIG. 3 when the strap is slack, a peg 16
is enclosed. When the strap is tensioned, the peg becomes visible
indicating tension in the strap, in the same way as exposure of the
belt indicates tensioning of the strap in FIG. 2.
* * * * *