U.S. patent application number 15/384958 was filed with the patent office on 2017-06-22 for safety device.
The applicant listed for this patent is Jefferey Hunt. Invention is credited to Jefferey Hunt.
Application Number | 20170175391 15/384958 |
Document ID | / |
Family ID | 57794059 |
Filed Date | 2017-06-22 |
United States Patent
Application |
20170175391 |
Kind Code |
A1 |
Hunt; Jefferey |
June 22, 2017 |
Safety device
Abstract
A safety apparatus for fitting to a free end of an elongate
member, for example a reinforcing bar, has a sleeve portion
defining a receiving space for receiving a free end of the member
and providing an opening of the receiving space to allow insertion
of the member from a first end of the apparatus, and a covering
portion which provides a barrier to prevent passage of the member
through a second end of the safety device. The safety apparatus may
have a gripping part which is resiliently deformable, so that it is
resiliently deformed by insertion of the member so as to securely
grip metal member, and so that it returns to substantially its
non-deformed shape upon removal of the metal member. The receiving
space may be tapered.
Inventors: |
Hunt; Jefferey; (Ormeau,
AU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hunt; Jefferey |
Ormeau |
|
AU |
|
|
Family ID: |
57794059 |
Appl. No.: |
15/384958 |
Filed: |
December 20, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65D 59/06 20130101;
E04G 21/3252 20130101; E04C 5/161 20130101 |
International
Class: |
E04C 5/16 20060101
E04C005/16 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 22, 2015 |
AU |
2015905335 |
Claims
1. A safety device for fitting to a free end of an elongate member,
the safety apparatus comprising: a sleeve portion defining a
receiving space therein for receiving a free end of said elongate
member, and providing an opening of the receiving space to allow
insertion of an end of the elongate member into the receiving space
from a first end of the safety apparatus; and a covering portion
which provides a barrier to prevent passage of the end of the
elongate member through a second end of the safety device; wherein
the receiving space is elongate, the receiving space is at least
partly defined by a wall part which is resiliently deformable,
extends from the opening towards the second end of the safety
apparatus, and wherein the receiving space is tapered along its
length.
2. The safety device according to claim 1 wherein the safety
apparatus comprises a gripping part which is resiliently
deformable.
3. The safety device according to claim 2 wherein the gripping part
is resiliently deformed by insertion of the elongate member into
the receiving space, thereby to securely grip the metal member, and
such that the gripping part returns to substantially its
non-deformed shape upon removal of the elongate member from the
receiving space.
4. The safety device according to claim 1 wherein the covering
portion forms the second end of the safety device.
5. The safety device according to claim 1 wherein the wall part
defines a generally circular transverse cross section of the
receiving space.
6. A safety device for fitting to a free end of a reinforcing bar,
the safety device comprising: a sleeve portion defining a receiving
space therein for receiving a free end of a reinforcing bar, and
providing an opening of the receiving space to allow insertion of a
reinforcing bar into the receiving space from a first end of the
safety device; and a covering portion which provides a barrier to
prevent passage of a reinforcing bar through a second end of the
safety device; wherein the receiving space is space is elongate,
extends from the opening towards the second end of the safety
device, and wherein the receiving space is tapered along its
length.
7. The safety device according to claim 6 wherein the receiving
space is at least partly defined by a wall part which is
resiliently deformable.
8. The safety device according to claim 7 wherein the wall part is
resiliently deformable such that the wall part is resiliently
deformed by insertion of a reinforcing bar into the receiving
space, thereby to securely grip the reinforcing bar, and such that
the wall part returns to substantially its non-deformed shape upon
removal of the reinforcing bar.
9. The safety device according to claim 1 wherein the receiving
space is tapered in a plurality of steps.
10. The safety device according to claim 9 wherein the covering
portion is impregnated with a metallic component.
11. The safety device according to claim 1 wherein the receiving
space is greater in transverse cross sectional size at or adjacent
the opening and reduces in cross sectional size as it extends
towards the second end of the safety device.
12. The safety device according to claim 1 wherein the receiving
space is generally frustoconical.
13. The safety device according to claim 1 wherein the wall part
extends substantially the entire length of the receiving space.
14. The safety device according to claim 1 wherein the wall part is
substantially annular in transverse cross section.
15. The safety device according to claim 1 wherein the covering
portion defines a curved second end surface of the safety
device.
16. The safety device according to claim 15 wherein the curved end
surface provides a rounded second end of the safety device.
17. The safety device according to claim 15 wherein the curved end
surface rapidly broadens with distance from the second end.
18. The safety device according to claim 15 wherein the curved end
surface is part spherical.
19. The safety device according to claim 15 wherein the curved end
surface is part ellipsoidal.
Description
FIELD
[0001] The present disclosure relates to a safety device and
especially, but not exclusively to a safety device in the form of
an end cap, for fitting to a free end of a steel reinforcing bar,
that reduces the risk of injury to workers in the vicinity of the
reinforcing bar.
DEFINITION
[0002] In the specification the term "comprising" shall be
understood to have a broad meaning similar to the term "including"
and will be understood to imply the inclusion of a stated integer
or step or group of integers or steps but not the exclusion of any
other integer or step or group of integers or steps. This
definition also applies to variations on the term "comprising" such
as "comprise" and "comprises".
BACKGROUND
[0003] Steel reinforcing bars, often called reo bars, are widely
used in construction, to reinforce concrete structures. During
construction it is not uncommon for a reinforcing bar to project
from a concrete structure or surface, resulting in a free end of
the reinforcing bar presenting a significant safety hazard.
Reinforcing bars are typically (but not always) generally circular
in transverse cross section, and typically have a diameter between
about 10 mm and about 40 mm. The free ends of reinforcing bars may
include rough, sharp or burred surfaces and can cause injuries if
inadvertently walked into, impacted upon or even brushed against.
Further, being quite small in transverse cross section and quite
stiff, especially in short lengths such as those which project from
concrete surfaces on a construction site, reinforcing bars may
impale a worker causing serious injury or death if fallen upon.
SUMMARY
[0004] According to a first aspect of the present disclosure there
is provided a safety device for fitting to a free end of a
reinforcing bar, the safety device comprising:
[0005] a sleeve portion defining a receiving space therein for
receiving a free end of a reinforcing bar, and providing an opening
of the receiving space to allow insertion of a reinforcing bar into
the receiving space from a first end of the safety device; and a
covering portion which provides a barrier to prevent passage of a
reinforcing bar through a second end of the safety device;
[0006] wherein the receiving space is at least partly defined by a
wall part which is resiliently deformable such that the wall part
is resiliently deformed by insertion of a reinforcing bar into the
receiving space, thereby to securely grip the reinforcing bar, and
such that the wall part returns to substantially its non-deformed
shape upon removal of the reinforcing bar.
[0007] In an embodiment the covering portion forms the second end
of the safety device.
[0008] In an embodiment the wall part defines a generally circular
transverse cross section of the receiving space.
[0009] In an embodiment the wall part comprises an elastomeric
material.
[0010] In an embodiment the wall part comprises a polyurethane
material.
[0011] In an embodiment the wall part extends substantially the
length of the sleeve portion.
[0012] In an embodiment the wall part is integrally formed with the
sleeve portion.
[0013] In an embodiment the wall part is integrally formed as part
of the sleeve portion.
[0014] In an embodiment the sleeve portion and the wall part are
formed as a single piece.
[0015] In an embodiment the sleeve portion and the wall part are
formed as a single, integrally moulded, piece.
[0016] In an embodiment at least most of the sleeve portion is made
of an elastomeric material.
[0017] In an embodiment at least most of the sleeve portion is made
of a polyurethane material.
[0018] In an embodiment substantially all of the sleeve portion is
made of an elastomeric material.
[0019] In an embodiment substantially all of the sleeve portion is
made of a polyurethane material.
[0020] In an embodiment the receiving space is elongate.
[0021] In an embodiment the receiving extends from the opening
towards the second end of the safety device.
[0022] In an embodiment the receiving space is generally
cylindrical.
[0023] In an embodiment the receiving space is tapered along its
length.
[0024] In an embodiment the receiving space is tapered
substantially uniformly along its length.
[0025] In an embodiment the receiving space is tapered in a
plurality of steps.
[0026] In an embodiment the receiving space is greater in
transverse cross sectional size at or adjacent the opening and
reduces in cross sectional size as it extends towards the second
end of the safety device.
[0027] In an embodiment the receiving space tapers by at least 0.5
mm in transverse width.
[0028] In an embodiment the receiving space tapers by at least 1 mm
in transverse width.
[0029] In an embodiment the receiving space tapers by no more than
about 6 mm in transverse width.
[0030] In an embodiment the receiving space tapers by no more than
about 4 mm in transverse width.
[0031] In an embodiment the receiving space is generally
frustoconical.
[0032] In an embodiment the wall part extends substantially the
entire length of the receiving space.
[0033] In an embodiment the wall part is substantially annular in
transverse cross section.
[0034] In an embodiment the wall part has a thickness of at least 2
mm.
[0035] In an embodiment the wall part has a thickness of at least
2.5 mm.
[0036] In an embodiment the wall part has a thickness of at least 3
mm.
[0037] In an embodiment the covering portion defines a curved
second end surface of the safety device.
[0038] In an embodiment the curved end surface provides a rounded
second end of the safety device.
[0039] In an embodiment the curved end surface rapidly broadens
with distance from the second end.
[0040] In an embodiment the curved end surface rapidly broadens
with distance from the second end, to a transverse size which is
greater than the mean transverse size of the sleeve portion.
[0041] In an embodiment the curved end surface is part
spherical.
[0042] In an embodiment the curved end surface is part
ellipsoidal.
[0043] In an embodiment a wall portion of the covering portion
which extends between a closed end of the cavity and the second end
of the safety device is thicker than a wall portion of the sleeve
portion.
[0044] In an embodiment a transversely extending wall portion
extends between the curved end surface and an outer surface of the
sleeve portion.
[0045] In an embodiment the transversely extending wall portion
extends between the curved end surface and an outer surface of the
sleeve portion.
[0046] In an embodiment the transversely extending wall portion is
substantially annular.
[0047] In an embodiment the receiving space extends past the
transversely extending wall portion.
[0048] In an embodiment a venting passage extends between a part of
the receiving space spaced from the opening and an exterior of the
device.
[0049] In an embodiment the covering portion is formed integrally
with the sleeve portion.
[0050] In an embodiment the sleeve portion and the covering portion
are formed as a single piece.
[0051] In an embodiment the sleeve portion and the covering portion
are formed as a single, integrally moulded, piece.
[0052] In an embodiment substantially the entire safety device is
formed as a single, integrally moulded, piece.
[0053] In an embodiment at least most of the safety device is made
of an elastomeric material.
[0054] In an embodiment at least most of the safety device is made
of a polyurethane material.
[0055] In an embodiment substantially the entire safety device is
made of an elastomeric material.
[0056] In an embodiment substantially the entire safety device is
made of a polyurethane material.
[0057] According to a second aspect of the present disclosure there
is provided a safety device for fitting to a free end of a
reinforcing bar, the safety device comprising:
[0058] a sleeve portion defining a receiving space therein for
receiving a free end of a reinforcing bar, and providing an opening
of the receiving space to allow insertion of a reinforcing bar into
the receiving space from a first end of the safety device; and a
covering portion which provides a barrier to prevent passage of a
reinforcing bar through a second end of the safety device;
[0059] wherein the receiving space is space is elongate, extends
from the opening towards the second end of the safety device, and
wherein the receiving space is tapered along its length.
[0060] In an embodiment the receiving space is at least partly
defined by a wall part which is resiliently deformable.
[0061] In an embodiment the wall part is resiliently deformable
such that the wall part is resiliently deformed by insertion of a
reinforcing bar into the receiving space, thereby to securely grip
the reinforcing bar, and such that the wall part returns to
substantially its non-deformed shape upon removal of the
reinforcing bar.
[0062] It will be appreciated that embodiments of the safety device
in accordance with the third aspect may include any one or more of
the features or characteristics defined above in relation to
embodiments of the first aspect.
[0063] According to a third aspect of the present disclosure there
is provided a safety apparatus for fitting to a free end of an
elongate member, the safety apparatus comprising:
[0064] a sleeve portion defining a receiving space therein for
receiving a free end of said elongate member, and providing an
opening of the receiving space to allow insertion of an end of the
elongate member into the receiving space from a first end of the
safety apparatus; and a covering portion which provides a barrier
to prevent passage of the end of the elongate member through a
second end of the safety device;
[0065] wherein the safety apparatus comprises a gripping part which
is resiliently deformable, and wherein the gripping part is
resiliently deformed by insertion of the elongate member into the
receiving space, thereby to securely grip the metal member, and
such that the gripping part returns to substantially its
non-deformed shape upon removal of the elongate member from the
receiving space.
[0066] In an embodiment the gripping part comprises a wall part
which at least partly defines the receiving space.
[0067] In an embodiment the safety device is for fitting to a free
end of a metal member.
[0068] In an embodiment the safety device is for fitting to a free
end of a reinforcing bar.
[0069] According to a fourth aspect of the present disclosure there
is provided a safety apparatus for fitting to a free end of an
elongate member, the safety apparatus comprising:
[0070] a sleeve portion defining a receiving space therein for
receiving a free end of said elongate member, and providing an
opening of the receiving space to allow insertion of an end of the
elongate member into the receiving space from a first end of the
safety apparatus; and
[0071] a covering portion which provides a barrier to prevent
passage of the end of the elongate member through a second end of
the safety device;
[0072] wherein the receiving space is space is elongate, extends
from the opening towards the second end of the safety apparatus,
and wherein the receiving space is tapered along its length.
[0073] In an embodiment the safety apparatus comprises a gripping
part which is resiliently deformable.
[0074] In an embodiment the gripping part is resiliently deformed
by insertion of the elongate member into the receiving space,
thereby to securely grip the metal member, and such that the
gripping part returns to substantially its non-deformed shape upon
removal of the elongate member from the receiving space.
[0075] Embodiments of the safety devices in accordance with the
third or fourth aspects may have any one or more of the features
defined above in relation to embodiments of the first aspect.
[0076] It will be appreciated that embodiments of the safety
devices in accordance with the third or fourth aspects may include
any one or more of the features or characteristics defined above in
relation to the first aspect and/or embodiments of the first
aspect.
[0077] Some embodiments of the third and fourth aspects may be for
fitting to a free end of an elongate member other than a
reinforcing bar: thus references to a "reinforcing bar" used in
relation to the first aspect or embodiments thereof should be taken
to be to an "elongate member or a "metal member" when considered in
relation to the third or fourth aspects, for consistency and in
order to properly define or describe features or characteristics of
such embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0078] Embodiments will be described below, in detail, with
reference to accompanying drawings. The primary purpose of this
detailed description is to instruct persons having an interest in
the subject matter of the invention how to carry the invention into
practical effect. However, it is to be clearly understood that the
specific nature of this detailed description does not supersede the
generality of the statements in the Summary above, but rather
relates to examples only. In the accompanying diagrammatic
drawings:
[0079] FIG. 1 is a perspective view of an embodiment of a safety
device in accordance with the present disclosure;
[0080] FIG. 2 is a side elevation of the embodiment of FIG. 1;
[0081] FIG. 3 is a cross section on of FIG. 2;
[0082] FIG. 4 is a cross sectional view of a variation of the
embodiment of FIG. 1 1 to 3, adapted for fitting to a reinforcing
bar of a smaller diameter.
[0083] FIG. 5 is a schematic cross sectional illustration of the
embodiment of FIGS. 1 to 3 with a reinforcing bar inserted
thereinto;
[0084] FIG. 6 is a schematic cross sectional illustration of the
embodiment of FIGS. 1 to 3, illustrating secure fitting to a
reinforcing, even after damage to a region that receives a
reinforcing bar;
[0085] FIG. 7 is a schematic cross sectional illustration of an
alternative embodiment showing a variation to the embodiment
illustrated in FIGS. 1 to 3; and
[0086] FIG. 8 is a perspective view of a further alternative
embodiment;
[0087] FIG. 9 is a side elevation of the embodiment of FIG. 8;
[0088] FIG. 10 is a cross section on X-X of FIG. 9; and
[0089] FIG. 11 is a schematic cross sectional illustration of an
embodiment of a two-part mould suitable for injection moulding the
embodiment illustrated in FIGS. 1 to 3.
DETAILED DESCRIPTION OF EMBODIMENTS
[0090] With reference to FIGS. 1 to 3 an embodiment of a safety
device in accordance with the present disclosure is in the form of
a cap 1 for fitting to a free end of a reinforcing bar.
[0091] The cap 1 has a first end 2 and a second end 3.
[0092] A part of the cap 1 which extends from the first end 2
towards the second end 3 comprises a sleeve portion which in the
illustrated embodiment is in the form of a generally cylindrical
portion 10.
[0093] The generally cylindrical portion 10 has an outer wall
surface 12, an end wall surface 14 which in this embodiment is
substantially perpendicular to the outer wall surface, and an inner
wall surface 16 which defines a cavity 18. The generally
cylindrical portion 10 may thus be considered to comprise a
generally cylindrical wall 17, between the outer wall surface 12
and the inner wall surface 16.
[0094] The cavity 18 is substantially coaxial with the generally
cylindrical portion 10. The cavity 18 is an example of a receiving
space for receiving a free end of a reinforcing bar (not shown in
FIGS. 1 to 3).
[0095] The cavity 18 has an opening 19 at the first end 2 of the
cap 1.
[0096] The opening 19 is defined by the end wall surface 14.
[0097] The cavity 18 extends longitudinally most, but not all, of
the length of the cap 1. In the illustrated embodiment the cavity
18 extends longitudinally about 80 to 90 percent of the length of
the cap 1. The end of the cavity further from the first end 1 is
defined by a cavity end wall surface 21.
[0098] In the illustrated embodiment the cavity 18 is somewhat
tapered, and has a wider region 20 at or close to the first end 2
of the cap 1 and a narrower region 22, close to where it terminates
at the cavity end wall surface 21, further from the first end 2. In
the illustrated embodiment the taper of the cavity 18 is smooth and
continuous, and the rate of taper is uniform along the length of
the cavity. The cavity 18 may be regarded as substantially
frustoconical in shape. However, it will be appreciated that in
variations the rate of taper need not be uniform and that a stepped
configuration of the inner wall 16 could be used if desired.
[0099] In the illustrated embodiment the thickness of the wall 17
of the cylindrical portion 10 is approximately 3 mm to 6 mm at the
first end 2 of the cap 1, and the generally cylindrical portion 10
is approximately 30 mm to 70 cm long, and approximately 20 mm to 35
mm in outside diameter. However, it will be appreciated that the
proportions and dimensions of variations of the device may be
varied as desired and appropriate: for example, the diameter of the
generally cylindrical portion may be adjusted to provide a cavity
of diameter suitable for any desired size of reinforcing bar; the
outer surface of the generally cylindrical portion may be somewhat
tapered, if desired; and the length of the generally cylindrical
portion may be adjusted to provide a longer or shorter cavity (for
receipt of a greater or lesser length of a reinforcing bar) as
desired. Variations may be dimensioned to accommodate reinforcing
bars of any size desired, including bars which are used to form a
steel mesh for reinforcing concrete structures and which may have a
diameter of approximately 5 mm. It should also be appreciated that
variations may be provided for reinforcing bars with cross sections
other than circular cross sections, and cavities of cross sectional
shape corresponding to the cross sectional shape of the reinforcing
bar (for example square or rectangular cross section) may be
provided. A more detailed description of the dimensions of a
particular embodiment of the illustrated cap 1 is provided
below.
[0100] A part of the cap 1, which extends from and defines the
second end 3 of the cap 1, comprises a robust end part 24. The end
part 24 is substantially solid, although in the illustrated
embodiment the cavity 18 extends a short distance into the end
part. The end part 24 of the illustrated embodiment is an example
of a covering portion which provides a barrier to prevent passage
of a reinforcing bar located in the cavity 18 through the second
end of the safety device.
[0101] The end part 24 has a curved outer surface 26 defining the
second end of the safety device.
[0102] In the illustrated embodiment the curved outer surface 26 is
substantially part-spherical. In the cap 1, the radius of curvature
of the substantially part-spherical outer surface 26 is greater
than the radius of the generally cylindrical portion 10.
[0103] The curved outer surface 26 provides a rounded second end of
the safety device and rapidly broadens to a transverse size which
is greater than the transverse size of the generally cylindrical
portion 10. Thus it should be appreciated that in alternative
embodiments the shape of the curved outer surface need not be
strictly part-spherical but could, for example, be
part-ellipsoidal.
[0104] In the cap 1 the radius of curvature of the substantially
part-spherical outer surface 26 is greater than the maximum radius
of the end part 24. Thus in this embodiment the part-spherical
outer surface 26 defines somewhat less than half a sphere.
[0105] The solid end part 24 is connected to an end of the
generally cylindrical portion 10 which is distal from the first end
2 of the cap 1. Where the end part 24 is connected to the generally
cylindrical portion 10 a transversely extending, and in this
embodiment, substantially annular, wall surface 28 connects, and
extends between, the curved outer surface 26 of the solid end part
24 and the outer wall surface 12 of the generally cylindrical
portion 10.
[0106] In the illustrated embodiment the cap 1 is formed from a
robust elastomeric material, for example a suitable polyurethane
polymer. This allows the inner wall surface 16 which defines the
cavity 18 to be resiliently deformed by insertion of an end of a
reinforcing bar into the cavity 18. Depending on the relative
diameters of the cavity 18 and the reinforcing bar, and the force
applied, the wall 17 may be deformed across it entire thickness.
The resilience of the material biases the inner wall surface 16
towards its non-deformed configuration, which causes it to grip the
reinforcing bar.
[0107] This provides a connection between the reinforcing bar and
the cap 1 which is highly resistant to inadvertent removal of the
cap 1 from the reinforcing bar, but which allows the cap 1 to be
removed from the free end of the reinforcing bar when desired.
[0108] The transversely extending wall surface 28 may provide a
convenient surface for a user to grip in order to facilitate
removal, for example by pulling the cap 1 off the free end of the
reinforcing bar. However, it should be appreciated that in the
illustrated embodiment the transversely extending wall surface 28
is fairly small in transverse width (for example about a centimetre
in the embodiment illustrated in FIGS. 1 to 3) to minimise the
likelihood of it being inadvertently caught on clothing, equipment
or carried items of a worker moving past the cap 1.
[0109] Further, when the cap 1 is removed from the reinforcing bar
(or, equivalently in relation to this description, when the
reinforcing bar is removed from the cavity 18), the inner wall
surface 16 returns substantially to its non-deformed configuration.
The cap 1 can then be re-used if desired, for example by fitting to
a different reinforcing bar.
[0110] In an embodiment the material is UV protected. The UV
protection may comprise use of one or more of: a UV absorber, such
as for example a benzotriazole; a quencher; and, a stabiliser, such
as for example a suitable hindered amine stabiliser. The UV
protection may comprise use of a combination of two or more of
these three types of protection.
[0111] In an embodiment the cap 1 is brightly coloured to make the
free end conspicuous in use. The cap 1 may be brightly coloured
and/or fluorescent. The cap 1 may be pigmented with a brightly
coloured and/or fluorescent pigment. Caps, or more generally safety
devices in accordance with the present disclosure, may be coloured
such that different colours are used to indicate suitability for
fitting to differently sized reinforcing bars. For example, a
safety device for fitting to a 15 mm diameter reinforcing bar might
be fluorescent orange, and a safety device for fitting to a 13 mm
diameter reinforcing bar might be fluorescent yellow.
[0112] It will be appreciated that variations of the cap 1 may be
made to any appropriate size to allow fitting to a desired size, or
diameter of reinforcing bar. The diameter of the cavity 18 varies
along the length of the cavity from a diameter slightly greater
than the diameter of the reinforcing bar with which it is to be
used to a diameter slightly less than the diameter of the
reinforcing bar with which it is to be used.
[0113] In a practical example, consistent with the embodiment
illustrated in FIGS. 1 to 3, the diameter of the cavity 18 varies
along the length of the cavity from a diameter about 0.5 mm to 1 mm
greater than the diameter of the reinforcing bar with which it is
to be used to a diameter about 0.5 mm to 2 mm less than the
diameter of the reinforcing bar with which it is to be used.
[0114] In one practical example, consistent with the embodiment
illustrated in FIGS. 1 to 3, the cap 1 is suitable for fitting to a
reinforcing bar of 15 mm diameter. In this example the overall
length of the cap 1 is about 68 mm, the length of the cylindrical
portion 10 is about 55 mm, the outside diameter of the cylindrical
portion 10 is about 25 mm, the cavity 18 extends approximately 3 mm
into the end part 24, the wall thickness of the end part 24
(between the end of the cavity 18 and the second end of the cap 1,
along the central axis of the cap 1) is about 10 mm, and the
transverse, or radial, width of the transversely extending wall 28
is about 10 mm. The cavity 18 tapers from a maximum diameter of
about 16 mm to a minimum diameter of about 14 mm. As discussed
above, dimensions and proportions may be varied if desired,
especially in embodiments suitable for fitting to other sizes of
reinforcing bar, although it may be desirable to provide a range of
caps for fitting to two or more different sizes of reinforcing bar
which have the same external dimensions and in which only the
dimensions of the cavity (including the associated) opening is
varied.
[0115] FIG. 4 is a schematic cross sectional illustration of a cap
1A, which is a variation of the cap 1. The cap 1A is identical to
the cap 1 in all respects except that it provides a cavity 18A
which is smaller in diameter than the cavity 18 of cap 1 and
accordingly provides a wall 17A which corresponds to, but is
thicker than, the wall 17 of cap 1. The cap 1A is adapted for
receipt of a reinforcing bar of smaller diameter than is the cap 1.
The similarities between the cap 1A of FIG. 4 and the cap 1 of
FIGS. 1 to 3 will not be described in detail, but it is worth
noting that the external dimensions of the cap 1A may be the same
as corresponding external dimensions of the cap 1, since this is of
relevance to manufacture of the caps 1 and 1A as will be described
in detail in due course, with reference to FIG. 11. The cap 1A may
be suitable for use with a reinforcing bar with a diameter of 13
mm, and the cavity 18A may taper from a maximum diameter of about
14 mm to a minimum diameter of about 12 mm.
[0116] FIG. 5 is a schematic cross sectional illustration of the
embodiment of FIGS. 1 to 3 in use. As FIG. 5 relates to use of the
cap 1, the same reference numerals as are used in FIGS. 1 to 3 are
used in FIG. 5 to indicate corresponding parts of the cap 1.
[0117] FIG. 5 is a schematic cross sectional illustration of the
embodiment of FIGS. 1 to 3 with a reinforcing bar 50 inserted into
the cavity 18 of the cap 1. The deformation of the inner wall 16 is
illustrated by the slight overlap of the reinforcing bar 50 over
the inner wall 16.
[0118] In use the cap 1 may be applied to the reinforcing bar 50,
by pushing the cap 1 onto the free end of the reinforcing bar 50.
Application of an appropriate amount of force will cause at least
the inner wall 16 to become deformed by contact with the
reinforcing bar 50. That is, at least some of the inner wall 16 is
pushed outwards by contact with the reinforcing bar 50. The elastic
resilience of the elastomeric material from which the cap is made
biases the inner wall 16 towards its non-deformed configuration,
thereby causing the inner wall 16 to securely grip the reinforcing
bar 50. The strength of the grip may be adjusted by the force with
which the cap 1 is pushed onto the reinforcing bar 50. Broadly
speaking, pushing the cap 1 onto the reinforcing bar with greater
force will force the reinforcing bar 50 further into the tapered
cavity 18, and thus into a transversely smaller part of the tapered
cavity 18, resulting in greater deformation of the inner wall 16,
greater elastic restoring force, and therefore greater grip.
[0119] It should be appreciated that, although not illustrated in
FIG. 5, the entire thickness of the wall 17 of the cylindrical
portion 10 may be deformed by insertion of the reinforcing bar 50,
as described above, although deformation of the outer wall surface
will normally be negligible or small (although this will depend
upon the thickness of the wall 17, which may vary between
embodiments and between caps adapted for use with differently sized
reinforcing bars).
[0120] It should also be appreciated that, although not illustrated
in FIG. 5, reinforcing bars may not have smooth outer surfaces, but
that protrusions or ridges may be provided thereon. Provision of
protrusions or ridges on a reinforcing bar has not been found to
detract substantially from the gripping of a reinforcing bar by the
inner wall 16. To the contrary, such irregularities may enhance
grip.
[0121] It should be appreciated that the taper of the cavity 18
contributes to the cap 1 being able to be securely fitted to a
reinforcing bar of a given nominal diameter, even if the actual
diameter varies slightly from the nominal diameter, or if there are
protrusions or ridges on a reinforcing bar. The taper of the cavity
18 can also allow a user to adjust how securely the cap is
connected to a reinforcing bar by adjusting the amount of force
used to push the cap 1 onto the reinforcing bar 50. If desired, the
cap 1 can be tapped further onto the reinforcing bar with a hammer
or the like to increase the security of the attachment.
[0122] The use of a suitably robust elastomer, such as a tough
polyurethane, makes the cap 1 very durable and resistant to damage
in use. Accordingly the cap 1 can be expected to survive a large
number of uses. However, the ends of reinforcing bars often include
burrs or sharp edges, and despite the toughness of the material
damage, scoring or wear of the inner wall 16 may occur in use.
[0123] FIG. 6 illustrates use of the cap 1 after damage to the
inner wall 16 has occurred. The damaged parts of the inner wall 16
are shown schematically and indicated by the reference numeral 65.
The damaged parts 65 are located in the region that accommodates
the end of the reinforcing bar 50 in an undamaged cap 1, as can be
seen by a comparison of FIG. 6 with FIG. 5.
[0124] As shown in FIG. 6, after a considerable number of uses
which have resulted in damaged parts 65 of the inner wall 16, the
cap 1 can be again reused, and securely fitted to a further
reinforcing bar 50A (which may be substantially identical to a
reinforcing bar, e.g. reinforcing bar 50, with which the cap 1 has
previously been used).
[0125] This is achieved by simply forcing the cap onto the
reinforcing bar 50A until is securely attached. Application of a
suitable amount of force moves the cap further onto the reinforcing
bar 50A, which effectively forces the reinforcing bar 50A further
into the taper of the cavity 18, where the narrower transverse
dimensions of the cavity 18 ensure that the end region of the
reinforcing bar 50A is adequately gripped, and the connection
secure. A firm push on the second end of the cap 1 will often be
sufficient, but if necessary or desired the cap 1 can be tapped
further onto the reinforcing bar with a hammer or the like. The
resilience of the material from which the cap 1, and more
specifically the wall 17, is made allows sufficient deformation to
accommodate the reinforcing bar 50A further along the cavity
18.
[0126] Thus it should be appreciated that the tapered form of the
cavity 18 and the elastic resilience of the material from which the
wall 17 is made act synergistically to allow considerable
adjustment of the security of the connection (of the cap 1 to a
reinforcing bar 50, 50A) and multiple uses of the cap 1.
[0127] If the cavity were tapered, but an elastically resilient
material were not used, the security of the attachment could still
be adjusted to some extent by varying the force applied to push the
cap onto the reinforcing bar, but some permanent damage to the
inner wall defining the cavity would likely occur with each use.
Such a cap could also be appropriate for re-use, but the damage to
the interior wall would likely increase substantially with each
subsequent use in which the cap is forced further onto a
reinforcing bar. Thus while such a cap might allow both adjustment
of connection strength and re-use, the combination of adjustment of
connection strength and a large number of uses would not be as
effectively provided as in the described embodiment.
[0128] If an elastically resilient material were to be used, but
the cavity were not tapered, again the security of the attachment
could still be adjusted to some (albeit a lesser) degree by varying
the extent to which the cap is forced onto the reinforcing bar, but
it would be likely that the cap would be pushed further onto the
reinforcing bar in the earliest use or uses, and therefore damage
to the inner wall defining the cavity would likely occur closer to
the closed end of the cavity earlier than in the illustrated cap 1,
reducing the useful life of the cap. Thus, again, while such a cap
might allow both adjustment of connection strength and re-use, the
combination of adjustment of connection strength and a large number
of uses would not be as effectively provided as in the described
embodiment.
[0129] Thus while the present disclosure extends to safety devices
having only one of the tapered cavity and elastically resilient
material, it will be appreciated that a further benefit is provided
by a safety cap which has both of these characteristics.
[0130] FIG. 7 is a schematic cross sectional illustration showing a
variation to the embodiment illustrated in FIGS. 1 to 3. As the
embodiment of FIG. 7 is generally similar in function and
construction to the cap 1 of FIGS. 1 to 3, only the dissimilarities
from the cap 1 of FIGS. 1 to 3 are described in detail below.
[0131] FIG. 7 is a schematic cross sectional illustration of an
embodiment of a safety device in the form of a cap 701, showing a
variation to the embodiment illustrated in FIGS. 1 to 3. In this
embodiment a venting passage 760 with small transverse cross
section, connects cavity 718 (corresponding to the cavity 18 of cap
1) to the outside of an end part 724 (corresponding to the end part
24 of cap 1) of the cap 701. The venting passage 760 avoids an
inner end region 722 of the cavity 718 being sealed with respect to
the outside of the cap 701 by a reinforcing bar (not shown in FIG.
7) when a free end of the reinforcing bar is within the cavity 718
and in firm contact with an inner wall 716 that defines the cavity
718. The provision of venting passage 760 can thereby avoid
creation of a high pressure region in the cavity 718 (during
connection) which could provide undesired resistance to attachment
of the cap to the reinforcing bar, or of a low pressure region in
the cavity 718 (during disconnection, or attempted disconnection)
which could provide undesired resistance to separation of the cap
701 from the reinforcing bar.
[0132] FIGS. 8 to 10 illustrate an alternative embodiment of a
safety device in the form of a cap 800 which is similar in
structure and function to the caps 1 and 1A but which differs to
some degree in shape and proportions. Only the differences will be
described.
[0133] An end part 824 of cap 800 corresponds broadly to end part
24 of cap 1, but forms a greater proportion of the length of the
cap. The end part provides an end part surface 826 which is
substantially hemispherical. The end part 824 is proportionately
narrower than the end part 24 of cap 1. A transversely extending
wall 828 corresponds broadly to transversely extending wall 28 of
cap 1 but is proportionately about 50% narrower than the
transversely extending wall 28 of cap 1.
[0134] Providing the narrower end part 824 may assist in minimising
potential obstructions to users, for example when used in
situations where reinforcing bar free ends are close together and
workers must move between them. However, the consequent provision
of a narrower transversely extending wall 828, may reduce the grip
available to a user when removing an end cap. Further the narrower
end part might not distribute force as effectively, especially in
the case of a direct longitudinal impact.
[0135] Providing the longitudinally thicker end part 824, which is
more steeply inclined at its sides may assist in deflecting certain
impacts, but may also make the end part 824 absorb lateral impacts
less gently, and requires use of more material in manufacture,
which may increase cost.
[0136] The cap 800 may therefore be considered to have some working
advantages and some working disadvantages compared to the cap 1.
However, the cap 800 shares many of the working advantages of the
cap 1.
[0137] It should be appreciated that the embodiments described are
configured suitably to allow manufacture by injection moulding.
[0138] FIG. 11 illustrates schematically an embodiment of a
two-part mould 1100, suitable for forming, for example, the cap
1.
[0139] The mould 1100 comprises a first mould part 1110 which
defines a substantially cylindrical cavity 1112 suitable for
forming the generally cylindrical portion 10 of cap 1. Within the
cylindrical cavity 1112 of the first mould part 1110 there is
provided a void former, which in this embodiment is in the form of
a frustoconical element 1118 for providing a void (in an injection
moulded product) corresponding to the cavity 18 of cap 1. In the
illustrated embodiment the void former is coaxial with the
cylindrical cavity 1112, and extends slightly from an open end of
the cavity 1112, to correspond to the cavity extending slightly
into the end part 24 of cap 1.
[0140] The mould 1100 further comprises a second mould part 1120
which defines a substantially part-spherical cavity 1124, suitable
for forming the end part 24 of cap 1.
[0141] When the first and second mould parts 1110, 1120 are brought
together the cavities 1112, 1124 together define a combined cavity
with a form corresponding to the form of the cap 1. The combined
cavity can be filled with a liquid material which is elastomeric
when set (e.g. a molten thermosetting polyurethane), via an
injection passage (not shown). The liquid material can then be
allowed to set to provide a safety device (for example in the form
of cap 1) as a single-piece injection-moulded device.
[0142] The first and second mould parts 1110, 1120 can then be
separated to allow removal of the injection-moulded safety
device.
[0143] The void former (frustoconical element 1118, in the
illustrated embodiment) for forming a void corresponding to cavity
18 may be removably connected to the first mould part 1110 by a
suitable coupling/decoupling arrangement. This allows replacement
of the void former with a void former of a different size, for
example a void former (not shown) which has a smaller (or greater)
transverse size, suitable for forming a smaller (or larger)
diameter cavity, such as for example the cavity 18A of the end cap
1A illustrated in FIG. 4. Thus a single mould provided with two or
more void formers of different transverse sizes may be used to
manufacture safety devices adapted for use with different sizes of
reinforcing bar, by selection of the desired void former.
[0144] FIG. 11 includes a schematic illustration of an example of a
suitable coupling/decoupling arrangement for the void former. As
illustrated, the frustoconical element 1118 is provided with a
first coupling part, in this embodiment in the form of a projection
1119, which can be removably coupled with, and retained in relation
to, a second coupling part, in this embodiment in the form of a
socket 1117, provided in the first mould part 1110. The first and
second coupling parts may be removably coupled by means of any
suitable retention arrangement, such as (but not limited to) a
friction fit, a bayonet arrangement, or complementary screw
threads. Each void former could be provided with a generally
corresponding first coupling part to allow coupling to, and
decoupling from, the mould. It should be appreciated that
alternative coupling/decoupling arrangements could be used (for
example an arrangement in which a projection of the mould part can
be removably inserted into, and retained in, a socket provided in
the void former).
[0145] As mentioned above the mould 1100 is illustrated
schematically, and a practical embodiment may include cavities for
moulding several safety devices simultaneously.
[0146] It will be appreciated that the embodiments of safety
devices described above can substantially reduce the risk of,
and/or the seriousness of, injury resulting from inadvertent
contact with the free end of a reinforcing bar.
[0147] In use the cap 1, 1A is pushed onto the free end of a
reinforcing bar to cover the free end of the reinforcing bar. Any
burrs or sharp surfaces at or close to the free end of the
reinforcing bar are therefore covered by the cap.
[0148] The substantially part-spherical outer surface 26 of the
solid end part 24 provides a smooth and relatively soft free end,
in contrast to the hard, and possibly sharp, free end of the
reinforcing bar.
[0149] Further the resiliently deformable nature of the elastomeric
material from which the end part 24 is formed can effectively
cushion impacts on the free end.
[0150] The rounded, or part-spherical second end of the cap (which
is the `free` end in use) increases the likelihood of any glancing
impact being deflected, rather than resulting in a more direct
impact on an end part of a reinforcing bar.
[0151] Further, the end part 24 has a greater cross sectional size,
in a direction perpendicular to an axis of elongation of the cap 1,
than a reinforcing bar which can be received in the cavity 18, and
in use distributes force to lessen the severity of an impact with
the end of the reinforcing bar.
[0152] Use of the cap 1, 1A can therefore greatly reduce the risk
of injury from, and can reduce the risk of impalement upon, a free
end of a reinforcing bar.
[0153] Further the described embodiments provide a safety device
which resiliently grips a reinforcing bar, allowing secure
engagement of the safety device with the reinforcing bar. This can
provide a low risk of inadvertent detachment but allow deliberate
removal when desired.
[0154] The taper in the cavity can allow a user to adjust how
securely the cap is connected to a reinforcing bar. If desired, the
cap can be tapped further onto the reinforcing bar with a hammer or
the like to provide a very secure attachment.
[0155] The transversely extending wall 28 can provide a convenient
surface which can be gripped in order to facilitate removal of the
cap from a reinforcing bar. If the cap is too securely attached to
be removed by hand, the transversely extending wall 28 may be
tapped with a hammer or the like, or a tool suitable for bearing
against the transversely extending wall 28 may be used. For
example, tools which could be applied to bear against diametrically
opposed regions of the transversely extending wall 28 without
bearing unduly on the cylindrical portion of the cap include, but
are not limited to: suitably sized or adjustable spanners or
wrenches; suitable pliers especially pliers with a slip-joint
and/or suitably curved jaws; and some tools with suitably robust
prongs or claws that are spaced apart by a distance equal to or
very slightly greater than the diameter of the cylindrical portion
of the cap.
[0156] Further, once removed from a reinforcing bar the gripping
part of each of the described caps returns substantially to its
original shape, allowing reuse.
[0157] Further, the taper in the cavity (e.g. cavity 18) can assist
in allowing reuse of the cap multiple times, even if the interior
wall of the cavity has been worn and/or damaged by previous contact
with sharp parts of the reinforcing bars with which the cap has
previously been used.
[0158] In contrast to the described embodiments, a previously
attempted way of attaching a device to the end of a rod or bar of
circular cross section comprises use of a relatively inelastic
plastic (that is, a material less elastic than an elastomer) to
provide a cylindrical connection portion with a cylindrical cavity
that is greater in diameter than the diameter of the rod or bar to
be received, and providing inwardly projecting vanes which project
from the internal wall defining the cavity towards the central axis
of the cavity. The vanes can assist in stabilising the device on
the bar end, but are considered not to provide a connection as
secure as that provided by described embodiments. Further, the
vanes are typically inelastically deformed by contact with the bar
or rod and, especially if deformed sufficiently to provide a
connection approaching a secure connection, do not return to their
original shapes after removal of the device from the bar or rod.
Thus such arrangements are not suitable for re-use, or if reused
will typically not provide a secure attachment to the bar or
rod.
[0159] Furthermore, the size of head or diameter of the safety
device or cap can be changed so as to suit various attachments and
meet regulatory standards in the industry.
[0160] The cap may be made from any suitable material.
[0161] The safety device or cap may be presented in any colour or a
combination of colours.
[0162] Moreover, additional material or components such as metal or
a suitable material may be placed or impregnated into any part of
the safety device such as the covering portion or head, or wall to
make the safety device or cap stronger. Preferably, the metal is
impregnated onto the covering portion or head portion of the safety
device or cap.
[0163] The safety device or cap according to the present invention
is not limited for use in scaffolding. The safety device or cap may
be modified as required for use in other products to provide safety
including star picket fencing.
[0164] It should be appreciated that the embodiments and principles
described herein may have applicability to provision of a safety
end cap for use with free ends of members other than reinforcing
bars. For example, on construction sites projecting free ends of
metal pipes metal pipes may present a hazard that may be mitigated
by use of a safety device in accordance with the present
disclosure.
[0165] Modifications and improvements may be incorporated without
departing from the scope of the invention described herein.
* * * * *