U.S. patent application number 13/656618 was filed with the patent office on 2013-02-21 for connector for stick.
The applicant listed for this patent is Dae Up SOHN. Invention is credited to Dae Up SOHN.
Application Number | 20130045041 13/656618 |
Document ID | / |
Family ID | 38815298 |
Filed Date | 2013-02-21 |
United States Patent
Application |
20130045041 |
Kind Code |
A1 |
SOHN; Dae Up |
February 21, 2013 |
CONNECTOR FOR STICK
Abstract
A locking mechanism for poles includes a support rod, inserted
into a first unit shaft at a first end thereof and locked to a
second unit shaft at a second end thereof, with threads formed
around the outer circumferential surface thereof; and a pressure
locking unit movably engaged with the threads of the support rod
and having longitudinal slits formed to open in one direction and
at least two pressure parts formed in a longitudinal direction. The
locking pressure of the pressure locking unit is imposed on the
unit shafts at multiple longitudinally spaced points, thus
dispersing or distributing the locking strength in the longitudinal
direction and increasing both the locking strength and the
resistance against both longitudinal compressive force and
longitudinal tensile force, thereby preventing the locked unit
shafts from suddenly slipping towards each other.
Inventors: |
SOHN; Dae Up; (Seoul,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOHN; Dae Up |
Seoul |
|
KR |
|
|
Family ID: |
38815298 |
Appl. No.: |
13/656618 |
Filed: |
October 19, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
13307723 |
Nov 30, 2011 |
|
|
|
13656618 |
|
|
|
|
12517861 |
Jun 5, 2009 |
|
|
|
PCT/KR2007/006271 |
Dec 5, 2007 |
|
|
|
13307723 |
|
|
|
|
Current U.S.
Class: |
403/109.1 |
Current CPC
Class: |
A45B 7/00 20130101; Y10T
403/7056 20150115; Y10T 403/7058 20150115; A45B 2009/005 20130101;
Y10T 403/32467 20150115; Y10T 403/32516 20150115; A45B 9/00
20130101; F16B 7/1463 20130101; Y10T 403/32501 20150115 |
Class at
Publication: |
403/109.1 |
International
Class: |
F16B 7/14 20060101
F16B007/14 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 5, 2006 |
KR |
10-2006-0122285 |
Dec 28, 2006 |
KR |
10-2006-0135853 |
Claims
1. A locking mechanism for poles, comprising: a support rod
inserted into a first unit shaft at a first end thereof and locked
to a second unit shaft at a second end thereof, with threads formed
around part of an outer circumferential surface of the support rod;
and a pressure locking unit movably engaged with the threads of the
support rod through screw-type engagement, with at least one pair
of longitudinal slits formed in the pressure locking body such that
the slits are open in one direction, and with two or more pressure
parts formed in the pressure locking body in a longitudinal
direction, wherein the pressure locking unit comprises: a pressure
locking body having a pair of first slits and a pair of second
slits, which are formed in the pressure locking body such that the
first and second slits are angularly spaced apart from each other
at right angles, wherein the pressure locking body comprises: an
annular-shaped first pressure part formed around a first edge of
the pressure locking body and an annular-shaped second pressure
part spaced apart from the first pressure part; and an
annular-shaped third pressure part formed around a second edge of
the pressure locking body and an annular-shaped fourth pressure
part spaced apart from the third pressure part, wherein the first
and second slits are opened in opposite directions, the support rod
is provided both with a first tapered shoulder part at a location
near a first end of the threads and with a second tapered shoulder
part at a location near a second end of the threads, and the
pressure locking body is provided on an inner circumferential
surface thereof with a tapered seat part so as to correspond to the
first tapered shoulder part of the support rod.
Description
TECHNICAL FIELD
[0001] The present invention relates, in general, to locking
mechanisms for poles and, more particularly, to a locking mechanism
for poles, which releasably locks a plurality of unit shafts of a
pole to each other.
BACKGROUND ART
[0002] Generally, poles are long thin pieces that may be used for
various purposes, such as walking sticks for hiking or trekking or
support poles for tents.
[0003] Such poles are typically used by aged people, physically
handicapped people, hikers and trekkers. Further, poles may be used
as a symbol of dignity or for self-protection by some people. Thus,
such poles may be called walking sticks, staffs or canes.
[0004] In recent years, the structures of poles have been developed
such that the poles comprise a plurality of assemblable unit shafts
instead of an integrated single shaft having a fixed length. Thus,
the assemblable poles proposed in recent years can be conveniently
stored when not used and the lengths thereof can be easily adjusted
as desired.
[0005] The conventional poles having the assemblable structures are
configured to realize locking between neighboring unit shafts
thereof on one surface (that is, one surface locking), so that the
poles can somewhat efficiently resist compressive force. However,
when tensile force is applied to the pole by pulling two locked
unit shafts from each other in opposite directions, both the
frictional force and the locking strength between the two locked
unit shafts are reduced, so that slippage may occur between the two
locked unit shafts and the locked state between the two unit shafts
may be released, thus sometimes subjecting users to safety
hazards.
DISCLOSURE OF INVENTION
Technical Problem
[0006] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the related art, and is
intended to provide a locking mechanism for poles, which increases
the locking strength of locked unit shafts of a pole, thus
realizing improved utility and improved quality of the poles.
Technical Solution
[0007] In order to accomplish the above object, the present
invention provides a locking mechanism for poles, comprising: a
support rod inserted into a first unit shaft at a first end thereof
and locked to a second unit shaft at a second end thereof, with
threads formed around part of an outer circumferential surface of
the support rod; and a pressure locking unit movably engaged with
the threads of the support rod through screw-type engagement, with
at least one pair of longitudinal slits formed in the pressure
locking body such that the slits are open in one direction, and
with two or more pressure parts formed in the pressure locking body
in a longitudinal direction.
[0008] In an aspect, the pressure locking unit may comprise a
pressure locking body, the pressure locking body comprising: an
annular-shaped first pressure part provided around an edge of a
first end of the pressure locking body; and an annular-shaped
second pressure part formed by a pressure protrusion formed around
an outer circumferential surface of the pressure locking body, and
the support rod may comprise a tapered shoulder part at a
predetermined location near the threads, wherein the pressure
locking body is provided on an inner circumferential surface
thereof with a tapered seat part so as to correspond to the tapered
shoulder part of the support rod.
[0009] In another aspect, the pressure locking unit may comprise a
pressure locking body having a pair of first slits and a pair of
second slits, which are formed in the pressure locking body such
that the first and second slits are angularly spaced apart from
each other at right angles, wherein the pressure locking body
comprises: an annular-shaped first pressure part formed around a
first edge of the pressure locking body and an annular-shaped
second pressure part spaced apart from the first pressure part; and
an annular-shaped third pressure part formed around a second edge
of the pressure locking body and an annular-shaped fourth pressure
part spaced apart from the third pressure part, wherein the first
and second slits are opened in opposite directions, the support rod
is provided both with a first tapered shoulder part at a location
near a first end of the threads and with a second tapered shoulder
part at a location near a second end of the threads, and the
pressure locking body is provided on an inner circumferential
surface thereof with a tapered seat part so as to correspond to the
first tapered shoulder part of the support rod.
[0010] In a further aspect, the pressure locking unit may comprise:
a first pressure locking body having both at least one pair of
slits and an annular-shaped first pressure part formed around an
edge of the first pressure locking body; and a second pressure
locking body having both at least one pair of slits and an
annular-shaped second pressure part formed around an edge of the
second pressure locking body.
[0011] In yet another aspect, the support rod may comprise: first
threads formed around an outer circumferential surface of the
support rod; a tapered shoulder part formed around the support rod
at a location above the first threads; and second threads formed
around the support rod at a location above the tapered shoulder
part and having a diameter less than that of the first threads,
wherein the first pressure locking body is movably engaged with the
second threads of the support rod through screw-type engagement,
the support rod is provided on the second threads with a wedge part
having a tapered outer circumferential surface, the first pressure
locking body is provided on an inner circumferential surface
thereof with a first tapered seat part so as to correspond to the
tapered outer circumferential surface of the wedge part, and the
second pressure locking body is movably engaged with the first
threads of the support rod through a screw-type engagement, and is
provided on an inner circumferential surface thereof with a second
tapered seat part so as to correspond to the tapered shoulder part
of the support rod.
[0012] In still another aspect, the pressure locking unit may
comprise a pressure locking body, with at least one pair of first
slits and at least one pair of second slits formed in upper and
lower ends of the pressure locking body such that the first and
second slits are open upwards and downwards, respectively, wherein
the pressure locking body is provided with annular-shaped first and
second pressure parts around upper and lower edges thereof.
[0013] In still another aspect, the support rod may be provided
with threads formed around an outer circumferential surface
thereof, a tapered shoulder part formed at a location above the
threads, and a wedge part formed in a lower portion of the threads
and having a tapered outer circumferential surface, the pressure
locking body may be movably engaged with the threads of the support
rod through screw-type engagement, and may be provided on a portion
of the inner circumferential surface thereof having the first
slits, with a first tapered seat part so as to correspond to the
tapered shoulder part of the support rod, and may be provided on
another portion of the inner circumferential surface thereof having
the second slits with a second tapered seat part so as to be in
contact with the tapered shoulder part of the wedge part.
[0014] In still another aspect, the locking mechanism for poles may
further comprise: an elastic member provided on a lower end of the
support rod.
[0015] The above and other objects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description when taken in conjunction with the
accompanying drawings. The technical terms and words used, both in
the description and in the claims, must not be interpreted
according to their dictionary meanings, but must be interpreted to
have meanings or concepts pertinent to the scope and spirit of the
invention, based on the principle by which the inventor can
appropriately define the technical terms and words to explain the
invention in the best way.
Advantageous Effects
[0016] As described above, the locking mechanism for poles
according to the present invention is advantageous in that it has
two or more pressure parts spaced apart from each other in a
longitudinal direction, thus realizing a multiple pressurizing
structure and causing pressure to act on two or more points at the
junction between the pressure locking body and a unit shaft, and
increasing the locking strength between two locked unit shafts.
[0017] Further, in the present invention, the locking pressure of
the pressure locking body is applied to a unit shaft at
longitudinally spaced points, so that the locking strength of the
locking mechanism can be dispersed or distributed in a longitudinal
direction, and the resistance of the two locked unit shafts against
compressive force or tensile force acting in a longitudinal
direction can be increased, and the two locked unit shafts can be
prevented from suddenly slipping toward each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an exploded perspective view illustrating a
locking mechanism for poles according to a first embodiment of the
present invention;
[0019] FIG. 2 is a sectional view illustrating the assembled
locking mechanism inserted into a unit shaft of a pole according to
the first embodiment of the present invention;
[0020] FIG. 3 is a sectional view illustrating the locking
operation of the locking mechanism according to the first
embodiment of the present invention;
[0021] FIG. 4 is an exploded perspective view illustrating a
locking mechanism for poles according to a second embodiment of the
present invention;
[0022] FIG. 5 is a sectional view illustrating the assembled
locking mechanism inserted into a unit shaft of a pole according to
the second embodiment of the present invention;
[0023] FIG. 6 is a sectional view illustrating the locking
operation of the locking mechanism according to the second
embodiment of the present invention;
[0024] FIG. 7 is an exploded perspective view illustrating a
locking mechanism for poles according to a third embodiment of the
present invention;
[0025] FIG. 8 is a partially sectioned view of the assembled
locking mechanism, taken along line A-A of FIG. 7;
[0026] FIG. 9 is a view taken along line A-A of FIG. 7,
illustrating the locking operation of the locking mechanism;
[0027] FIG. 10 is a view taken along line B-B of FIG. 7,
illustrating the locking operation of the locking mechanism;
[0028] FIG. 11 is an exploded perspective view illustrating a
locking mechanism for poles according to a fourth embodiment of the
present invention;
[0029] FIG. 12 is a partially sectioned view of the assembled
locking mechanism taken along line C-C of FIG. 11;
[0030] FIG. 13 is a view taken along line C-C of FIG. 11,
illustrating the locking operation of the locking mechanism;
and
[0031] FIG. 14 is a view taken along line D-D of FIG. 11,
illustrating the locking operation of the locking mechanism.
DESCRIPTION OF REFERENCE CHARACTERS OF IMPORTANT PARTS
[0032] 11: support rod 12: pressure locking body
[0033] 13: retainer 17: elastic member
[0034] 51, 52: unit shafts
MODE FOR THE INVENTION
[0035] The above and other objects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description when taken in conjunction with the
accompanying drawings.
[0036] Hereinbelow, preferred embodiments of the present invention
will be described with reference to the accompanying drawings.
[0037] In the following description, it is to be noted that,
wherever possible, the same reference numerals will be used
throughout the drawings and the description to refer to the same or
like parts. Further, when the functions of conventional elements
and the detailed description of elements related to the present
invention may make the gist of the present invention unclear, a
detailed description of those elements will be omitted.
[0038] FIG. 1 through FIG. 3 are views illustrating a locking
mechanism for poles according to a first embodiment of the present
invention. As shown in the drawings, the locking mechanism for
poles according to the first embodiment of the present invention is
interposed between a pair of unit shafts 51 and 52 so as to
releasably lock the two unit shafts together and comprises a
support rod 11 and a pressure locking unit.
[0039] The support rod 11 is movably inserted into a first unit
shaft 51 at a first end thereof, and is fixed to a second unit
shaft 52 at a second end thereof.
[0040] The support rod 11 is provided with threads 11a on part of
the outer surface thereof. The support rod 11 further comprises a
tapered shoulder part 11c, which has a gradually reduced diameter
and is formed on the upper end of the threads 11a, and a
small-diameter tip part 11b, formed on the upper end of the tapered
shoulder part 11c.
[0041] The pressure locking unit comprises a single pressure
locking body 12 having at least one pair of main slits 12b. The
pressure locking body 12 is preferably made of an elastic material,
such as metal, rubber or plastic material. The pair of main slits
12b is longitudinally formed in the upper end of the pressure
locking body 12 such that they are diametrically opposed to each
other, and the pressure locking body 12 can be elastically opened
in opposite directions around the pair of main slits 12b.
[0042] Further, one pair of sub-slits 12f is formed in the pressure
locking body 12 at predetermined locations, which are angularly
spaced apart from the pair of main slits 12b at right angles, such
that the sub-slits 12f are diametrically opposed to each other. The
sub-slits 12f are slit in a longitudinal direction opposite the
slit direction of the main slits 12b, so that the sub-slits 12f
promote the elastic opening action of the pressure locking body 12
around the main slits 12b.
[0043] Further, the pressure locking body 12 has threads 12g in the
inner circumferential surface of one end thereof, so as to be
movably engaged with the threads 11a of the support rod 11 through
screw-type engagement. The upper end of the threads 12g of the
pressure locking body 12 is provided with a tapered seat part 12a,
which corresponds to the tapered shoulder part 11c of the support
rod 11.
[0044] The pressure locking body 12 is provided on the upper edge
thereof with an annular-shaped first pressure part 12c, which is
formed through, for example, chamfering. An annular protrusion 12d
is formed around the outer circumferential surface of the pressure
locking body 12 at a location longitudinally spaced apart from the
first pressure part 12c by a predetermined distance. A second
pressure part 12e is formed around the corner of the annular
protrusion 12d.
[0045] Further, as shown in FIG. 1, the pressure locking body 12 is
provided on the lower end thereof with an elastic member 17. The
elastic member 17 elastically biases the pressure locking body 12
in the longitudinal direction at the junction between the two
locked unit shafts 51 and 52.
[0046] The elastic member 17 is supported at the upper end thereof
by a retainer 13, and is supported at the lower end thereof on the
upper end of the second unit shaft 52. The retainer 13 is provided
with threads on the inner circumferential surface 13a thereof. The
inner circumferential surface 13a, having the threads, is engaged
with the lower end of the threads 11a of the support rod 11, thus
fixing the retainer 13 to the support rod 11.
[0047] The assembly of the locking mechanism for poles according to
the first embodiment of the present invention will be described in
detail hereinbelow.
[0048] As shown in FIG. 2, the second unit shaft 52, having the
support rod 11, is inserted into the first unit shaft 51 in the
state in which the second end of the support rod 11 is locked to
the second unit shaft 52. Thereafter, the second unit shaft 52 may
be rotated while gripping the first unit shaft 51 with a hand, or
the first unit shaft 51 may be rotated while gripping the second
unit shaft 52. Due to the relative rotation of the two unit shafts
51 and 52, the threads 11a of the support rod 11 and the threads
12g of the pressure locking body 12 undergo screw movement relative
to each other, so that the tapered shoulder part 11c of the support
rod 11 is advanced along the tapered seat part 12a of the pressure
locking body 12, as shown in FIG. 3, thus opening the pressure
locking body 12 outwards in radial directions around the main slits
12b. Thus, both the first pressure part 12c and the second pressure
part 12e of the pressure locking body 12 are pressed onto the inner
circumferential surface of the first unit shaft 51 outwards in the
radial directions, so that the pair of unit shafts 51 and 52 can be
securely locked together.
[0049] Therefore, the present invention provides a multiple
pressurizing structure using the first and second pressure parts
12c and 12e of the pressure locking body 12, thus realizing a
structural advantage in which the pair of unit shafts 51 and 52 can
be securely locked together.
[0050] Further, in the present invention, the pressure from the
pressure locking body 12 is imposed on the inner circumferential
surface of the unit shaft 51 at longitudinally spaced points, so
that the locking strength, realized by the pressure locking body
12, is dispersed or distributed in a longitudinal direction. Thus,
the present invention is advantageous in that the resistance of the
two locked unit shafts 51 and 52 against both the compressive force
and the tensile force, acting in longitudinal directions, can be
increased, and the locked unit shafts 51 and 52 can be prevented
from suddenly slipping toward each other.
[0051] In addition, when it is required to release or separate the
two locked unit shafts 51 and 52 from each other, either unit shaft
51 or 52 is rotated in a direction opposite the direction of the
above-mentioned locking process. Thus, the pressure locking body 12
executes screw movement relative to the threads 11b of the support
rod 11 in the opposite direction, so that the opened pressure
locking body 12 is closed around the main slits 12b and allows a
user to easily release or separate the two locked unit shafts 51
and 52 from each other.
[0052] FIG. 4 and FIG. 5 illustrate a locking mechanism for poles
according to a second embodiment of the present invention. As shown
in FIGS. 4 and 5, the locking mechanism for poles according to the
second embodiment of the present invention is interposed between
two locked unit shafts 51 and 52, and comprises a support rod 11
and a pressure locking unit.
[0053] The support rod 11 is movably inserted at a first end
thereof into the first unit shaft 51, and is fixed to the second
unit shaft 52 at a second end thereof.
[0054] The support rod 11 is provided with first threads 11a on
part of the outer surface thereof. The support rod 11 further
comprises a tapered shoulder part 11c, which has a gradually
reduced diameter and is formed on the upper end of the first
threads 11a. A small-diameter tip part 11b, having a diameter
smaller than that of the threads 11a, is formed on the upper end of
the tapered shoulder part 11c, with second threads 11d formed
around part of the small-diameter tip part 11b.
[0055] In the second embodiment, the pressure locking unit further
comprises first and second pressure locking bodies 22 and 23, which
are movably engaged with the support rod 11 through screw-type
engagement.
[0056] The first pressure locking body 22 is preferably made of an
elastic material, such as metal, rubber or plastic material. A pair
of main slits 22b is longitudinally formed in the lower end of the
first pressure locking body 22 such that they are diametrically
opposed to each other, and the first pressure locking body 22 can
be elastically opened in opposite directions around the pair of
main slits 22b. Further, a mounting slot 22e is formed in the first
pressure locking body 22 at a position above the main slits 22b,
with a nut 25 fitted in the mounting slot 22e so as to be movably
engaged with the second threads 11d of the support rod 11 through a
screw-type engagement.
[0057] Further, one pair of sub-slits (not shown) is formed in the
first pressure locking body 22 at predetermined locations, which
are angularly spaced apart from the pair of main slits 22b at right
angles, such that the sub-slits are diametrically opposed to each
other. The sub-slits are slit in a longitudinal direction opposite
the slit direction of the main slits 22b, so that the sub-slits
promote the elastic opening action of the first pressure locking
body 22 around the main slits 22b.
[0058] The first pressure locking body 22 is provided on the lower
edge thereof with an annular-shaped first pressure part 22c, which
is formed through, for example, chamfering. The first pressure
locking body 22 is provided on the upper inner circumferential
surface thereof with threads 22a so as to be movably engaged with
the second threads 11d of the support rod 11 through screw-type
engagement. A first tapered seat part 22d is provided in the first
pressure locking body 22 at a location beneath the threads 22a so
as to be in contact with and move relative to the outer
circumferential surface of a wedge part 24, which will be described
in detail later herein.
[0059] The wedge part 24 is a tapered body, the diameter of which
is gradually reduced in an upward direction. The tapered outer
circumferential surface of the wedge part 24 is in contact with the
first tapered seat part 22d of the first pressure locking body 22.
The lower surface of the wedge part 24 is supported by a washer 26,
which is fastened to the lower end of the second threads 11d of the
support rod 11.
[0060] In other words, when the first tapered seat part 22d of the
first pressure locking body 22 is moved relative to the outer
circumferential surface of the wedge part 24 while being in contact
therewith, the first pressure locking body 22 is opened around the
slits 22b, so that the first pressure part 22c is pressed onto the
inner circumferential surface of the first unit shaft 51.
[0061] The second pressure locking body 23 is preferably made of an
elastic material, such as metal, rubber or plastic material. A pair
of main slits 23b is longitudinally formed in the upper end of the
first pressure locking body 23 such that they are diametrically
opposed to each other, and the second pressure locking body 23 can
be elastically opened in opposite directions around the pair of
main slits 23b.
[0062] Further, one pair of sub-slits 23f is formed in the second
pressure locking body 23 at predetermined locations, which are
angularly spaced apart from the pair of main slits 23b at right
angles, such that the sub-slits 23f are diametrically opposed to
each other. The sub-slits 23f are slit in a longitudinal direction,
opposite the slit direction of the main slits 23b, so that the
sub-slits 23f promote the elastic opening action of the second
pressure locking body 23 around the main slits 23b.
[0063] The second pressure locking body 23 is provided on the inner
circumferential surface thereof with threads 23g, so as to be
movably engaged with the first threads 11a of the support rod 11. A
second tapered seat part 23a is provided in the second pressure
locking body 23 at a position above the threads 23g, so as to
correspond to the tapered shoulder part 11c of the support rod
11.
[0064] The second pressure locking body 23 may be is provided on
the upper edge thereof with an annular-shaped second pressure part
23c, which is formed through, for example, chamfering.
[0065] When the two unit shafts 51 and 52, having the locking
mechanism according to the second embodiment, are rotated relative
to each other in the same manner as that described for the first
embodiment, the tapered shoulder part 11c of the support rod 11
moves longitudinally relative to the second tapered seat part 23a
of the second pressure locking body 23 due to relative rotation
between the threads 23g of the second pressure locking body 23 and
the first threads 11b of the support rod 11. Thus, the second
pressure locking body 23 is opened around the main slits 23a, so
that the second pressure part 23c is pressed onto the inner
circumferential surface of the first unit shaft 51, as shown in
FIG. 6. In the above state, the first tapered seat part 22d of the
first pressure locking body 22 moves relative to the tapered outer
circumferential surface of the wedge part 24 while being in surface
contact therewith, so that the first pressure locking body 22 is
opened around the main slits 22b until the first pressure part 22c
is pressed onto the inner circumferential surface of the first unit
shaft 51. Thus, the two unit shafts 51 and 52 are locked
together.
[0066] The construction and operation of the locking mechanism
according to the second embodiment, except for the above-mentioned
construction and operation, remain the same as those of the first
embodiment, and further explanation is thus deemed unnecessary.
[0067] FIG. 7 through FIG. 9 illustrate a locking mechanism for
poles according to a third embodiment of the present invention. As
shown in FIGS. 7 through 9, the locking mechanism according to the
third embodiment of the present invention is interposed between two
locked unit shafts 51 and 52, and comprises a support rod 11 and a
pressure locking unit.
[0068] The support rod 11 is movably inserted into a first unit
shaft 51 at a first end thereof, and is fixed to a second unit
shaft 52 at a second end thereof.
[0069] The support rod 11 is provided with threads 11a on part of
the outer surface thereof. The support rod 11 further comprises a
tapered shoulder part 11c, which has a gradually reduced diameter
and is formed on the upper end of the threads 11a, and a
small-diameter tip part 11b, formed on the upper end of the tapered
shoulder part 11c.
[0070] The pressure locking unit according to the third embodiment
comprises a pressure locking body 31, with a pair of first slits
31a and a pair of second slits 31b formed in opposite ends of the
pressure locking body 31 so as to be open upwards and downwards,
respectively.
[0071] In the present invention, the first and second slits 31a and
31b may be formed on the opposite ends of the pressure locking body
31 such that they are circumferentially offset from each other on
the pressure locking body 31 (in FIG. 7, the first and second slits
31a and 31b are offset from each other so as to be perpendicular to
each other).
[0072] Alternatively, the first and second slits 31a and 31b may be
formed on the opposite ends of the pressure locking body 31 such
that they are arranged in the same axial plane.
[0073] Further, each of the first and second pairs of slits 31a and
31b is formed on the pressure locking body 31 such that each pair
of slits faces each other in the same manner as that described for
the first and second embodiments.
[0074] The pressure locking body 31 according to the third
embodiment may further comprise first and second sub-slits (not
shown), which are formed on the pressure locking body 31 at
locations angularly spaced apart from the first and second slits
31a and 31b at right angles. The first and second sub-slits (not
shown) of the third embodiment may execute the same function as in
the first and second embodiments.
[0075] As shown in FIG. 8, the pressure locking body 31 is
provided, on the inner circumferential surface thereof in a
predetermined portion having the first slits 31a, with a first
tapered seat part 31c so as to correspond to the tapered shoulder
part 11c of the support rod 11. Further, the first tapered seat
part 31c is provided, on the lower inner circumferential surface
thereof, with threads 31g so as to be movably engaged with the
threads 11a of the support rod 11 through screw-type
engagement.
[0076] As shown in FIG. 10, the pressure locking body 31 is also
provided, on the inner circumferential surface thereof at another
predetermined portion having the second slits 31b, with a second
tapered seat part 31f, which is in contact with the tapered outer
circumferential surface of the wedge part 34. Further, a mounting
slot 31h is formed in the pressure locking body 31 at a position
above the second slits 31b with a nut 35 fitted in the mounting
slot 31h so as to be movably engaged with the threads 11a of the
support rod 11 through screw-type engagement.
[0077] The lower end of the wedge part 34 may be supported by a
washer 36, which is fastened to the threads 11a of the support rod
11.
[0078] Further, the pressure locking body 31 is provided on the
upper and lower edges thereof with first and second annular-shaped
pressure parts 31d and 31e, which are formed through, for example,
chamfering.
[0079] When the pair of unit shafts 51 and 52 of the locking
mechanism according to the third embodiment is rotated relative to
each other in the same manner as those of the first and second
embodiments, the threads 31g of the pressure locking body 31 and
the threads 11a of the support rod 11 are rotated relative to each
other, so that the upper portion of the pressure locking body 31 is
opened around the first slits 31a due to relative movement between
the first tapered seat part 31c of the pressure locking body 31 and
the tapered shoulder part 11c of the support rod 11. Thus, the
first pressure part 31d of the pressure locking body 31 is pressed
onto a portion of the inner circumferential surface of the first
unit shaft 51, as shown in FIG. 9. Further, the lower portion of
the pressure locking body 31 is opened around the slot slits 31b
due to relative movement between the second tapered seat part 31f
and the wedge part 34. Thus, the second pressure part 31e of the
pressure locking body 31 is pressed onto another portion of the
inner circumferential surface of the first unit shaft 51, as shown
in FIG. 10, thus securely locking the two unit shafts 51 and 52 to
each other.
[0080] The construction and operation of the locking mechanism
according to the third embodiment, except for the above-mentioned
construction and operation, remain the same as those of the first
and second embodiments, and further explanation is thus deemed
unnecessary.
[0081] FIG. 11 through FIG. 14 illustrate a locking mechanism for
poles according to a fourth embodiment of the present invention. As
shown in FIGS. 11 through 14, the locking mechanism according to
the fourth embodiment of the present invention is interposed
between two locked unit shafts 51 and 52, and comprises a support
rod 11 and a pressure locking unit.
[0082] The support rod 11 is movably inserted into a first unit
shaft 51 at a first end thereof, and is fixed to a second unit
shaft 52 at a second end thereof.
[0083] The support rod 11 is provided with threads 11a on part of
the outer surface thereof. The support rod 11 further comprises a
first tapered shoulder part 11c, which has an upwardly gradually
reduced diameter and is formed on an upper end of the threads 11a,
and a second tapered shoulder part 11e, which has a downwardly
gradually increased diameter and is formed beneath the lower end of
the threads 11a. The second tapered shoulder part 11e is externally
threaded. Further, a small-diameter tip part 11b is formed on the
upper end of the tapered shoulder part 11c.
[0084] The pressure locking unit according to the fourth embodiment
comprises a single pressure locking body 42 having a first pair of
slits 42b and a second pair of slits 42f.
[0085] The single pressure locking body 42 is preferably made of an
elastic material, such as metal, rubber or plastic material. The
pair of first slits 42b is longitudinally formed in the upper end
of the pressure locking body 42 such that they are diametrically
opposed to each other, and the pressure locking body 42 can be
elastically opened in opposite directions around the pair of first
slits 42b, as shown in FIG. 13.
[0086] Further, the pair of second slits 42f is open in a direction
opposite the opening direction of the first slits 42b, and is
angularly spaced apart from the first slits 42b at a right angle.
The lower part of the pressure locking body 42 can be elastically
opened in opposite directions around the second slits 42f, as shown
in FIG. 14.
[0087] The pressure locking body 42 is provided on the first inner
circumferential surface thereof with threads 42g so as to be
movably engaged with the threads 11a of the support rod 11. A
tapered seat part 42a is formed in the pressure locking body 42 at
a position above the threads 42g so as to correspond to the first
tapered shoulder part 11c of the support rod 11.
[0088] The pressure locking body 42 is provided on the upper edge
thereof with an annular-shaped first pressure part 42c, which is
formed through, for example, chamfering. An annular protrusion 42d
is formed around the outer circumferential surface of the pressure
locking body 42 at a position spaced apart from the first pressure
part 42c by a predetermined distance. A second pressure part 42e is
formed around an edge of the annular protrusion 42d.
[0089] Further, the lower edge of the pressure locking body 42 is
provided with an annular-shaped third pressure part 42k. An
annular-shaped fourth pressure part 42j is formed around the
pressure locking body 42 at a position upwardly spaced apart from
the third pressure part 42k by a predetermined distance.
[0090] The assembly of the locking mechanism for poles according to
the fourth embodiment of the present invention will be described in
detail hereinbelow.
[0091] The second unit shaft 52, having the support rod 11, is
inserted into the first unit shaft 51, as shown in FIG. 12, in a
state in which the second end of the support rod 11 is locked to
the second unit shaft 52. Thereafter, the second unit shaft 52 may
be rotated while gripping the first unit shaft 51 in the hand, or
the first unit shaft 51 may be rotated while gripping the second
unit shaft 52. Due to the relative rotation of the two unit shafts
51 and 52, the threads 11a of the support rod 11 and the threads
42g of the pressure locking body 42 undergo screw movement relative
to each other.
[0092] Thus, the first tapered shoulder part 11c of the support rod
11 is advanced along the tapered seat part 42a of the pressure
locking body 42, as shown in FIG. 13, thus opening the upper part
of the pressure locking body 42 outwards in radial directions
around the first slits 42b. Therefore, both the first pressure part
42c and the second pressure part 42e of the pressure locking body
42 are pressed onto the inner circumferential surface of the first
unit shaft 51 outwards in radial directions.
[0093] In the same time, the second tapered shoulder part 11e of
the support rod 11 is moved relative to the lower inner
circumferential surface of the pressure locking body 42, as shown
in FIG. 14, thus opening the lower part of the pressure locking
body 42 in opposite directions around the second slits 42f.
Therefore, the third and fourth pressure parts 42k and 42j of the
pressure locking body 42 are pressed onto the inner circumferential
surface of the first unit shaft 51 outwards in radial
directions.
[0094] Briefly described, the locking mechanism for poles according
to the fourth embodiment of the present invention is advantageous
in that it can securely lock the two unit shafts 51 and 52 together
using a multiple pressurizing structure, realized by the first
through fourth pressure parts 42c, 42e, 42k and 42j of the pressure
locking body 42.
[0095] As described above, the pressure locking body 12, 22, 23,
31, 42 according to the present invention comprises two or more
pressure parts 12c, 12e, 22c, 23c, 31d, 31e, 42c, 42e, 42k, 42j,
which are spaced apart from each other in a longitudinal direction,
thus having a multiple pressurizing structure or a multiple contact
support structure. Therefore, locking pressure or frictional
contact locking force acts at the junction between the pressure
locking body and the first unit shaft at two or more points, thus
increasing the frictional force between the pressure locking body
and the first unit shaft and increasing the locking strength
between the two locked unit shafts 51 and 52.
[0096] Further, the present invention is advantageous in that the
locking pressure of the pressure locking body is applied to a unit
shaft at longitudinally spaced points, so that the locking strength
of the locking mechanism can be dispersed or distributed in a
longitudinal direction, and the resistance of the two locked unit
shafts against compressive force or tensile force acting in a
longitudinal direction can be increased, and the two locked unit
shafts can be prevented from suddenly slipping toward each
other.
[0097] Although the embodiments of the present invention have been
disclosed for illustrative purposes, those skilled in the art will
appreciate that various modifications, additions and substitutions
are possible, without departing from the scope and spirit of the
invention as disclosed in the accompanying claims.
* * * * *