U.S. patent application number 12/481547 was filed with the patent office on 2009-10-01 for device for relative fixing of elements telescopically displaced in each other.
Invention is credited to Lill-Hege Hagensen, Ragnar Stahle.
Application Number | 20090245927 12/481547 |
Document ID | / |
Family ID | 20280884 |
Filed Date | 2009-10-01 |
United States Patent
Application |
20090245927 |
Kind Code |
A1 |
Stahle; Ragnar ; et
al. |
October 1, 2009 |
DEVICE FOR RELATIVE FIXING OF ELEMENTS TELESCOPICALLY DISPLACED IN
EACH OTHER
Abstract
A locking device for two units (1), (3) displaceable one inside
the other, such as the handle of an implement with variable length,
comprising a locking member (4) arranged at one end of the outer
element (3), said locking member (4) being operated by an operating
member (5) spaced from the locking member (4) in the direction of
the other end of the outer element (3) via an actuating member (7)
that is displaceable along, or turnable about, an axis parallel
with the longitudinal axis of the outer element (3).
Inventors: |
Stahle; Ragnar; (Ljungskile,
SE) ; Hagensen; Lill-Hege; (Ljungskile, SE) |
Correspondence
Address: |
FASTH LAW OFFICES (ROLF FASTH)
26 PINECREST PLAZA, SUITE 2
SOUTHERN PINES
NC
28387-4301
US
|
Family ID: |
20280884 |
Appl. No.: |
12/481547 |
Filed: |
June 9, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12028975 |
Feb 11, 2008 |
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12481547 |
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11549626 |
Oct 13, 2006 |
7373708 |
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12028975 |
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10362767 |
Feb 24, 2003 |
7144180 |
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11549626 |
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Current U.S.
Class: |
403/109.5 |
Current CPC
Class: |
Y10T 403/7066 20150115;
F16B 7/1418 20130101; F16B 7/105 20130101; Y10T 403/32516 20150115;
Y10T 29/4984 20150115; F16B 7/149 20130101; Y10T 16/473 20150115;
F16B 7/10 20130101; Y10T 403/32467 20150115; B25G 1/04 20130101;
F16B 7/1445 20130101; Y10T 403/32501 20150115; F16B 7/1463
20130101; F16B 7/1454 20130101; Y10T 29/49863 20150115; Y10T
403/7077 20150115; Y10T 403/7064 20150115 |
Class at
Publication: |
403/109.5 |
International
Class: |
F16B 7/10 20060101
F16B007/10 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 3, 2000 |
SE |
0003117-9 |
Aug 31, 2001 |
SE |
PCT/SE01/01856 |
Claims
1-3. (canceled)
1. A locking device, comprising: a first element and a second
element, the first element having a lower free end being extandable
and axially movable from a first end of the second element in a
first direction, the first element being slidable inside the second
element, a locking member disposed at a lower region of the second
element for locking the first element relative to the second
element, an actuating member extending in a second direction away
from the first end of the second element towards a second opposite
end of the second element, the actuating member extending along the
second element, the second direction being opposite the first
direction, an operating member in operative engagement with the
actuating member and axially remote from the locking member, the
locking member being operable by the operating member via the
actuating member, the locking member having radially displaceable
tongue members that are contactable with a contact surface of the
first element, the tongue members being biased towards the first
element by a spring element providing a biasing force in a radial
direction wherein the tongue members engage a contact surface of
the first element to axially fix the first element relative to the
second element in a locked position, and the tongue members
comprising wedge-engaging surfaces cooperating with an engaging
member in connection with the actuating member for releasing an
engagement between the tongue members and the contact surface of
the first element, the wedge-engaging surfaces being substantially
tangentially directed wherein when the operating member is actuated
to axially move the actuating member and the engaging member,
sliding of the engaging member along the wedge engaging surfaces
radially releases the engagement between the tongue members and the
contact surfaces of the first element allowing the first element to
axially move relative to the second element in an unlocked
position.
2. A locking device, comprising: a first element and a second
element, the first element having a lower free end extendable and
axially movable from a first end of the second element in a first
direction, the first element being slidable inside the second
element, a locking member positioned at a lower region of the
second element for locking the first element relative to the second
element, an actuating member extending in a second direction away
from the first end of the second element towards a second opposite
end of the second element, the actuating member extending along the
second element, the second direction being opposite the first
direction, an operating member in operative engagement with the
actuating member and axially remote from the locking member, the
locking member being operable by the operating member via the
actuating member, the locking member having radially displaceable
tongue members that are contactable with a contact surface of the
first element, the tongue members being biased towards the first
element by a spring element providing a biasing force in a radially
inward direction wherein the tongue members engage the contact
surface of the first element to axially fix the first element
relative to the second element in a locked position, and the tongue
members comprising wedge-engaging surfaces cooperating with an
engaging member disposed on the actuating member for releasing an
engagement between the tongue members and the contact surface of
the first element, the wedge-engaging surfaces being substantially
tangentially directed wherein when the operating member is actuated
to axially move the actuating member and the engaging member in the
second direction, sliding of the engaging member along the wedge
engaging surfaces radially releases the engagement between the
tongue members and the contact surfaces of the first element
permitting the first element to axially move relative to the second
element in an unlocked position.
3. A locking device, comprising: a first element and a second
element, the first element having a lower free end extendable and
axially movable from a first end of the second element in a first
direction, the first element being slidable inside the second
element, a locking member disposed at a lower region of the second
element for locking the first element relative to the second
element, an actuating member extending in a second direction away
from the first end of the second element towards a second opposite
end of the second element, the actuating member extending along the
second element, the second direction being opposite the first
direction, an operating member in operative engagement with the
actuating member and axially remote from the locking member, the
locking member being operable by the operating member via the
actuating member, the locking member having radially displaceable
tongue members that are contactable with a contact surface of the
first element, the tongue members being biased towards the first
element by a spring element providing a biasing force in a radial
direction wherein the tongue members engage a contact surface of
the first element to axially fix the first element relative to the
second element in a locked position, and the tongue members
comprising wedge-engaging surfaces cooperating with an engaging
member in connection with the actuating member for releasing an
engagement between the tongue members and the contact surface of
the first element, the wedge-engaging surfaces being substantially
tangentially directed wherein when the operating member is actuated
to axially move the actuating member and the engaging member,
sliding of the engaging member along the wedge engaging surfaces
radially releases the engagement between the tongue members and the
contact surfaces of the first element permitting the first element
to axially move relative to the second element in an unlocked
position.
Description
PRIOR APPLICATIONS
[0001] This is a continuation patent application that claims
priority from continuation patent application Ser. No. 12/028,975
filed 27 Jun. 2007 that claims priority from U.S. national phase
patent application Ser. No. 11/549,626, filed 13 Oct. 2006 that
claims priority from 10/362,767, filed 24 Feb. 2003 that claims
priority from PCT/SE01/01856, filed 31 Aug. 2001, that claims
priority from Swedish Patent Application No. 0003117-9, filed 3
Sep. 2000.
TECHNICAL FIELD
[0002] The invention relates to a device for detachably locking two
elements in an optional position in relation to each other, said
elements being telescopically or turnably movable in relation to
each other with a certain clearance between the two elements, such
as a rod or pipe within an outer rod or within an outer sleeve.
BACKGROUND OF THE INVENTION
[0003] Many types of devices for detachably locking two
telescopically movable elements in relation to each other are
known, such as simple screw joints, cotter and hole joints, wedge
joints, conical ring joints, eccentric joints, etc. These devices
exhibit different properties and drawbacks.
[0004] Cotter and hole joints and other shape-dependent joints
(e.g. SE 870387-6) provide a secure connection but only allow
stepwise adjustment of the elements in relation to each other.
Other joints such as screw joints, are dependent on friction and
thus allow stepless setting, but they often require such high
contact forces to ensure reliable locking that the contact surfaces
become deformed.
[0005] SE 8203018-0 describes a device with an intermediate element
8 to spread the contact force over a larger area with the object of
avoiding damage to the contact surfaces. A drawback with this
device, however, is that the locking force is so great that a screw
must be used, which is an inconvenience.
[0006] EP 0209756 describes a device in which a rubber ring 4
having circular cross section is used as a locking and sealing
element. A drawback with this device, however, is that setting the
two elements in relation to each other is complicated since the
joint must be opened and the rubber ring rolled to the desired
position.
[0007] DE 3143793 describes a device in which a plastic washer 40
with a conical end piece is clamped between corresponding conical
surfaces on the outer and inner telescopic elements. A drawback
with this, however, is that the fit between the inner telescopic
element and the washer must be so accurate that it is rather
difficult to move it along the inner telescopic element. Another
drawback is that the washer is thus subject to wear.
[0008] Common to these known solutions is that they are generally
operated by movement of the operator's hand and that the operation
cannot be performed at a distance from the locking unit. In the use
of telescopically adjustable handles for implements, such as
cleaning handles, particularly cleaning handles for floor care such
as floor mops it is, for ergonomic reasons, extremely necessary to
be able to operate the telescopic function from the upper part of
the handle, without the need for any turning movement. From the
ergonomic aspect it is most advantageous if control can be
performed by means of pressure close to the upper part of the
handle, at right angles to the longitudinal axis of the handle, and
for the application of this pressure via a compressive movement of
the operator's hand to give rise to release of the locking
device.
BRIEF SUMMARY OF THE INVENTION
[0009] The main object of the present invention is to provide an
easily operated but, at the same time, extremely reliable device
for stepless and detachable locking of two elements that are
telescopically or turnably movable in relation to each other. The
device shall be usable in widely differing technical areas where
the stop positions between two elements must be changed. The device
is primarily intended for the handles of implements such as
cleaning handles, particularly cleaning handles for floor care,
such as floor mops. Other feasible areas of application are e.g.
sports equipment, stands, masts and frames.
[0010] Another object of the present invention is to provide a
device that permits adjustment of the position between the inner
and outer elements via a control spaced from the locking
device.
[0011] Another object of the present invention is to provide a
device that allows repeated, reliable locking of a desired position
between the inner and outer elements without any function-impairing
influence or wear occurring on the parts involved.
[0012] Yet another object of the present invention is to provide a
device that allows adjustment of the position between the inner and
outer elements without the need for any turning movement.
[0013] These objects are achieved by means of a device for
detachably locking two elements in an optional position, said
elements being telescopically or turnably movable in relation to
each other with a certain clearance between the two elements, such
as a rod or pipe within an outer rod or within an outer sleeve,
comprising a locking device operated by means of an operating
member spaced from the locking device, via an actuating member.
[0014] The invention will be described in more detail with
reference to the accompanying drawings, the latter being intended
to explain and not to limit the invention.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a view from the side showing the handle of an
implement with a device in accordance with the invention.
[0016] FIG. 2 is a partial view, partly in cross-section, in the
direction of the arrow A in FIG. 1, showing mostly the locking
device, in locked position.
[0017] FIG. 3 is a view B of the device as shown in FIG. 2
[0018] FIG. 4 is a view of the device as shown in FIG. 2, when
disconnected.
[0019] FIG. 5 is a view C of the device shown in FIG. 4.
[0020] FIG. 6 is a partial view, partly in cross-section, showing
mostly the operating member.
[0021] FIG. 7 is a partial view, partly in cross-section, showing
primarily the operating member in an alternative embodiment.
[0022] FIG. 8 is a partial view, partly in cross-section, showing a
locking device and an operating member without intermediate
actuating member, in locked position.
[0023] FIG. 9 is a partial view, partly in cross-section, showing a
device as shown in FIG. 8, when disconnected.
[0024] FIG. 10 is a partial view from the front of an embodiment of
the invention where the actuating member is omitted.
[0025] FIG. 11 is a partial view from the side, partly in
cross-section, of the device shown in FIG. 10 in which the device
is in a locked position.
[0026] FIG. 12 is a partial view as shown in FIG. 11 in which the
device is in an unlocked position.
[0027] FIG. 13 is a side view from the device where the inner
element is turned to face the operator.
[0028] FIG. 14 is a cross-sectional view of the locking member of
the device shown in FIG. 13.
[0029] FIG. 15 is a cross-sectional view of another embodiment of
the device of the present invention with a locking wedge pressed
against wedge-shaped grooves in the inner element.
[0030] FIG. 16 is a cross-sectional view of the embodiment, shown
in FIG. 15, in which the device is in an unlocked position.
[0031] FIG. 17 is cross-sectional top view of the inner element as
shown in FIGS. 15 and 16.
[0032] FIG. 18 is a partial side view of an inner element where a
number of rectangular holes are arranged in an axially directed
recess.
[0033] FIG. 19 is a cross-sectional top view of a locking member in
an unlocked position.
[0034] FIG. 20 is a cross-sectional top view of the locking member,
shown in FIG. 19, in a locked position.
[0035] FIG. 21 is a cross-sectional view of a locking member having
a tangentially displaceable locking yoke that can act on the
surface of the inner element.
[0036] FIG. 22 is a cross-sectional view of the locking member
shown in FIG. 21, where the locking yoke is operated by a knob.
[0037] FIG. 23 is a partial view from the front of a locking member
with a knob acting on the inner element via recesses in the outer
element.
[0038] FIG. 24 is a partial view of the locking member shown in
FIG. 23.
[0039] FIG. 25 is a rear view of a contact surface of the knob.
[0040] FIG. 26 is a cross-sectional of an inner element and an
outer element where the outer element has integrated locking
elements.
[0041] FIG. 27 is a cross-sectional view of the arrangement shown
in FIG. 26 where the inner element is locked to the outer
element.
[0042] FIG. 28 is a partial cross-sectional side view of the
arrangement shown in FIG. 26.
[0043] FIG. 29 is a cross-sectional view of different embodiments
of the locking elements in the outer element.
[0044] FIG. 30 is a front side view of an outer element that has
flaps punched out.
[0045] FIG. 31 is a left view of the outer element shown in FIG.
30.
[0046] FIG. 32 is a side view of the outer element shown in FIG.
30.
[0047] FIG. 33 is a front view of the outer element shown in FIGS.
30-32.
[0048] FIG. 34 is a left view of the device shown in FIG. 33.
[0049] FIG. 35 is a side view of the device shown in FIG. 33.
[0050] FIG. 36 is a front view of an alternative embodiment.
[0051] FIG. 37 is a front view of the embodiment shown in FIG. 36
where the operating member is pressed to lock the inner element
relative the outer element.
[0052] FIG. 38 is a front view of the embodiment shown in FIG. 36
where the operating member is blocked in a locked position.
[0053] FIG. 39 is a front view of a locking member.
[0054] FIG. 40 is a perspective view of the locking member shown in
FIG. 39.
[0055] FIG. 41 is a cross-sectional view along the lines A-A of the
locking member shown in FIG. 39.
[0056] FIG. 42 is a front view of a wedge.
[0057] FIG. 43 is a perspective view of the wedge shown in FIG.
42.
[0058] FIG. 44 is a perspective view of a cap.
[0059] FIG. 45 is a side view of the locking member, wedge, cap and
actuating member in an assembled position.
[0060] FIG. 46 is a view of operating member, actuating member and
the wedge in an assembled position.
DETAILED DESCRIPTION OF THE INVENTION
[0061] The device shown in FIG. 1 is the handle of an implement
comprising an inner element 1 with hole 2 for attachment of a
suitable implement. The inner element 1 is fitted into an outer
element 3 with a certain clearance. In this case the inner and out
elements 1 and 3, respectively, are tubular with suitable diameters
and are thus turnable in relation to each other. The inner element
1 is detachably locked to the outer element 3 with the aid of a
locking member 4. When not actuated the locking member 4 is locked
by spring elements, the function of which will be further explained
later in the description. A handle is fitted over the top of the
outer element 3, below which an operating member 5 is turnably
attached. Compression of the operating member 5 in the direction of
the arrow J releases the locking device 4 and the inner element 1
can then be turned and displaced in relation to the outer element
3. It is thus possible to adjust the handle of the implement to the
desired length and also to turn the implement to the desired angle
without the operator having to bend down. In practice adjustment of
the handle is effected by the operator moving his/her hand down
from the gripping handle 6 and pressing the operating member 5
towards the outer element 3. Thanks to the placing of the operating
member 5 in the upper part of the handle of the implement, the
operator need not bend his/her wrist during operation.
[0062] Furthermore, only one hand is required for the adjustment
since, upon compression of the operating member 5 in the direction
of the arrow J, the hand will also grip the outer element 3. The
properties described above are of great benefit to those who
frequently use such implements with handles. One such occupational
category is cleaning staff who spend most of their working hours
using cleaning handles, the length of which must frequently be
adjusted.
[0063] The device in accordance with the invention consists of
three logical units: the locking member, the operating member, and
an actuating member therebetween via which actuation of the
operating member is transmitted to the locking member. One of the
aims of the invention has been to achieve reliable locking with
small operating force and short operating distance. This aim is
achieved with an embodiment of the locking device as shown in FIGS.
2 and 3. The locking member 4 here consists of a partially slotted
rod, suitably of reinforced plastic, which is whole at the top and
forms an attachment collar 10, the latter being permanently
connected to the outer element 3. The lower part 8 of the rod is
partly separated from the upper part by a slot 17, the depth of the
slot being such that a relatively narrow neck connects the upper
part 10 and the lower part 8. The lower part 8 is cleft in axial
direction by a wedge-shaped groove 13 and thus forms two jaws 9
that are radially displaceable. Friction pads 12 are fixed on the
inside of these jaws 9, the pads being shaped to the envelope
surface of the inner element. These friction pads 12 may suitably
be made of rubber and can be taped to the inside of the jaws 9, or
of a rubber profile with ridges that can be inserted into
corresponding grooves in the jaws 9 (not shown in the drawing). The
jaws 9 are pressed with relatively strong force by the spring
elements 11 against the inner element 1 which is thus locked
against the outer element 3 via the friction pads 12. A wedge 14
fits into the groove 13 and is in connection with an actuating
member 7. This wedge 14 slides against the opposing edges in the
groove 13. The angle between these edges is so large that
self-locking of the wedge cannot occur and, when not actuated by
the operating member 5, this wedge 14 is always in the lower
position as shown in FIG. 2. FIGS. 4 and 5 show the locking device
4 when disconnected.
[0064] Under the influence of an operating force from the operating
member 5 the actuating member 7 is drawn in the direction of the
arrow F. The wedge 14 is thus drawn in the direction of the arrow G
into the groove 19 in the attachment collar 10. This groove 19 also
runs through the outer element 3 so that the wedge 14 can be freely
drawn in the direction of the arrow G. The wedge-shaped groove 13
is thus separated in tangential direction as indicated by the
arrows H. A small gap thus appears between the friction pads 12 and
the inner element 1 so that this can easily be displaced in
relation to the outer element 3 in the direction of the arrows I,
and can also be rotated. Under the influence of the operating force
the lower part 8 tends to bend and must therefore be support by a
peg 18 in the slot 17. Said peg 18 is rigidly attached to one of
the jaws 9 and, during the operation, slides against the edge of
the attachment collar 10. The wedge 14 is provided with internal
and external guiding edges 22,21, respectively, which keep the
wedge in place in the groove 13. For the sake of clarity the lower
part of the external guiding edge 21 is not shown in FIGS. 2 and 4.
Operation of the locking member 4 is thus performed via an
actuating member 7.
[0065] The actuating member 7 preferably comprises a thin tape for
which there is room in the narrow tap between the inner element 1
and the outer element 3, which is extremely advantageous. The tape
may be made of high-quality reinforced plastic, but is preferably
made of high-strength spring steel which is commercially available
in desired widths down to a thickness of 0.2 mm. The advantages of
such a steel tape are that it is strong and flexible but relatively
inelastic upon tensile stress.
[0066] The steel tape is bent perpendicularly outwards, fitted into
a through-slot 16 in the wedge 14 and bent downwards on the upper
side of the wedge 14. A through-hole is provided at the lower end
of the steel tape, into which the attachment screw 15 is fitted and
screwed into the wedge 14. The spring elements 11 preferably
consist of rings of spring steel which are standard products. The
advantages of this type of spring element are that they produce a
compact construction and that they enclose the jaws, thereby
supporting the jaws 9 along the entire envelope surface below which
the friction pads 12 are secured. The friction pads 12 can thus be
pressed against the inner element 1 from a long time without
causing any deformation in the jaws 9 that might impair the locking
function.
[0067] FIG. 6 shows a view, partly in cross-section, of a preferred
embodiment of the invention. To save space the outer element 3 is
shortened here and the operating member 5 is therefore a shorter
distance from the locking member 4 than is shown in FIG. 1. The
tongue 51 of the operating member 5 fits into slots in the outer
element. This tongue 5 is considerably narrower than the inner
diameter of the outer rod and is provided with a groove 55 riding
on a lower edge 54 of the upper groove of the outer element 3. The
operating member 5 can thus be turned around the edge 54 in the
direction of the arrow J. During this rotation the portion 52 is
moved in towards the free space 58 inside the outer element 3 and
forms a stop against the upper edge of the inner element so that
this cannot prevent rotation due to wedging. For the same reason
the portion 52 comprises an outwardly directed shoulder 53 which,
when the operating member is inactive, protrudes through a lower
slot in the outer element 3.
[0068] When the operating member 5 is turned towards its stop
position the shoulder 53 is in such a position that it stops the
inner element 1 so that this cannot prevent rotation by wedging.
The operating member 5 also comprises a wider grip 57 for
comfortable operation. The actuating member 7 is attached in the
operating member and in this embodiment is in the form of a steel
tape screwed to the operating member by means of the screw 56. The
steel tape rests against the edge of the operating member 5 and
follows this edge in towards the innermost edge of the tongue 51,
shaped with a radius. When the operating member 5 is compressed in
the direction of the arrow J, the tongue 51 is rotated upwards
towards the gripping handle 6. The steel tape is thus pulled in the
direction of the arrow F and the wedge 14 in the direction of the
arrow G. The inner element 1 is thereby disconnected from the outer
element 3 and can be freely displaced and rotated in relation
thereto without being impeded by the actuating member 7 since this
is so narrow that it only marginally fills the gap between the
inner and outer elements 1 and 3, respectively.
[0069] Practical tests have shown that if the operating member 5 is
actuated with a compressive force of 25 N for an operating distance
of 30 mm, an extremely reliable locking function can be released,
thereby resulting in very convenient operation for the operator.
Instead of hooking the operating member in the edge 55 of the outer
element 3 it would also be possible to store the tongue 51 of the
operating member 5 in a shaft running through the hollow in the
centre of the outer element 3. This results in a smaller lever and
the angle of rotation will be correspondingly greater.
[0070] FIG. 7 shows an embodiment of the operating member 5 having
the advantage of not intruding into the outer element 3 and
therefore not stopping the inner element 1, which can thus be
freely pushed past the operating member 5 to the desired position.
The operating member 5 is here turnably journalled in a yoke 25 via
the axis 26. The yoke 25 partially surrounds the outer element 3
and is rigidly connected thereto. The actuating member 7 protrudes
through a slot 27 in the envelope surface of the outer element
3.
[0071] FIGS. 8 and 9 show an embodiment of the invention in which
the actuating member 7 is omitted. The operating member 5 comprises
a U-shaped section partially surrounding the locking member 4 with
two flanges 61, two circular pins 60 being attached on the inside
of one of the flanges. A pin is rigidly attached on the inside of
the opposite flange, on a level exactly between the pins 60, fitted
into corresponding holes in the rear of the lower part 8. This
opposing pin, which is thus hidden in the figures, defines the
centre of rotation upon compression of the operating member 5. Pins
60 are fitted into corresponding semi-circular grooves 62 in
opposing edges of both jaws 9. Under the influence of a compressive
movement of the operating member 5 in the direction of the arrow J,
the wedge-shaped groove 13 is separated in tangential direction in
the direction of the arrows H. A small gap thus appears between the
friction pads 12 and the inner element 1, whereupon this can easily
be displaced in relation to the outer element 3 in the direction of
the arrows I, and can also be rotated. This embodiment has the
advantage of being cheaper to manufacture and gives a very reliable
and easily operated disconnection if operation need not occur at a
distance from the locking member.
[0072] In the above description the invention has been applied to
the handle of an implement. However, it can naturally be applied in
all areas in which elements need to be telescopically displaced and
rotated in relation to each other. The same inventive concept, with
an operating member placed at a distance from the locking device,
can be applied to other types of locking members than those
described above. However, it is preferable for the locking device
to be locked under influence of the spring element. The desired
displacement of the jaws 9 may also be achieved in many other ways
besides those described above. In the above description the jaws 9
are connected by a neck to an attachment collar 10. However, the
jaws 9 can naturally be displaceably attached to the outer element
3 in some other way, e.g. they may consist of separate parts
inserted into rectangular grooves in the outer element 3, or made
in one piece with the outer element. The spring elements 11 may,
furthermore, be designed in widely different ways and still give
the same compressive function. The invention has been described
above as applied to rods and pipes with circular cross section. The
same inventive concept can naturally also be applied to rods and
pipes with other cross sections, e.g. rectangular. The invention
can also be varied within the scope of the claims in ways obvious
to one skilled in the art.
[0073] The invention can be further varied within the scope of the
claims as follows: FIGS. 10,11,12 show partial views of an
embodiment of the invention where the actuating member 7 is
omitted. The operating member 5 comprises a U-shaped section which
partially surrounds the attachment collar 10 of the locking member
4 with two flanges 61.
[0074] Holes are arranged in the flanges for trunnion pins 70 that
are attached in the envelope surface of the attachment collar 10.
These trunnion pins 70 define the centre of rotation upon
compression of the operating member 5. Furthermore, as previously,
two radially displaceable jaws 9 are arranged to be opened under
the influence of the wedge 14. The wedge 14 is provided with an
upwardly directed extension 73 which engages in a driving slot (not
shown) in the interior of the operating member 5. A split washer 72
fulfils the same function as the peg 18 described earlier. The
lower part of the locking member 4 is covered by a cap 71, shown in
section in FIGS. 12 and 13. The cap fits against the support
flanges 73. FIG. 12 shows the locking device in disconnected
position. The operating member 5 has been turned about the trunnion
pins 70 by means of a compressive force J against the outer element
3.
[0075] The upwardly directed extension 73 of the wedge 14 is thus
drawn upwards in the figure and the wedge 14 has thus released the
locking device so that the inner element 1 can move freely in
relation to the outer element 3.
[0076] FIGS. 13 and 14 show another embodiment of the invention.
The inner element 1 is here turned to face the operator and the
lower end of the outer element 3 forms an attachment for an
implement through a hole 2. The locking member 4 is secured in the
lower part of the inner element 1 and fitted into the outer element
3. The locking device 4 comprises radially displaceable jaws 9
provided externally with friction pads. These are pressed outwards
by spring elements so that the inner element 1 is locked against
the outer element 3. Neither the friction pads nor the spring
elements are shown in the figure. Influenced by a wedge 14 with two
oppositely facing, angled sliding surfaces fitting corresponding
oppositely facing sliding surfaces on the inside of each jaw 9. An
actuating member 7 is attached to one part of the wedge 14.
[0077] This actuating member 7 is fitted into the inner element and
no space is therefore required for it between the inner and outer
elements, thus facilitating assembly. The actuating member 7 is
attached by its other end to the operating member 5. When the
operating member 5 is moved in the direction of the arrow J, the
actuating member 7 is drawn in the direction of the arrow F and the
wedge 14 presses the jaws 9 together, thereby releasing the locking
member. The locking member 4 may naturally be designed in many ways
within the scope of the inventive concept.
[0078] FIGS. 15,16 and 17 show yet another embodiment of the
invention.
[0079] The locking member 4 here comprises a housing 81 in which a
locking wedge 82 and a lever 85 are pivotably journalled via pins
83 and 86.
[0080] Influenced by a spring 84 the locking wedge is pressed
against corresponding wedge-shaped grooves in the inner element 1.
The locking force can be varied as desired depending on the wedge
angle.
[0081] When the actuating member 7 is drawn in the direction of the
arrow F, the lever 85 is turned so that the protruding piece 87
presses down the protruding piece 88 in the locking wedge 82. The
locking wedge 82 is thus drawn out of the wedge-shaped slot 80 in
the direction of the arrow G, and the inner rod is freely movable
in axial direction. This type of locking member 4 can thus also be
operated by an operating member at the desired distance.
[0082] The inventive concept of operation being performed at a
distance from the locking member can naturally be applied to many
different types of locks, including shape-dependent locks in
accordance with FIG. 18 where a number of rectangular holes 89 are
arranged in an axially directed recess in the inner element 1,
similar to the wedge-shaped groove 80 in FIG. 17. A pivotable lock
catch 82 can cooperate with the desired hole 89 so that stepwise
control of the axial position between the inner element 1 and the
outer element 3 can be achieved with an arrangement having a lever
85 etc, similar to that shown in FIGS. 15 and 16. This type of lock
can be varied in many ways, such as by replacing the holes 89 with
grooves produced by a press operation, for instance. The advantage
of shape-dependent locks is that they are generally cheaper to
manufacture and require considerably less operating force than
friction-dependent locks.
[0083] Most known locks for telescopically displaceable elements
are based on the principle of radially displaceable locking
elements applying force on the inner rod.
[0084] FIGS. 19-38 show variants on the principle of applying force
on the inner rod by means of tangentially displaceable locking
elements. The advantage of this is that the locking forces are
greater, due to the wedge action, despite relatively small
operating force.
[0085] FIGS. 19 and 20 show an inner rod 1 surrounded by a locking
housing 102 in which locking elements 103 can be displaced
tangentially towards the inner rod. Thanks to the angles a wedging
action is obtained such that the locking forces FL are greater than
the operating forces FM.
[0086] FIG. 21 shows a locking yoke 112 having locking surfaces
103. The locking yoke is inset in a recess in an outer rod 102. The
inner rod is thus locked against the locking surfaces 103 and the
opposing inner surface of the outer rod when the locking yoke 112
is moved to the left in the figure.
[0087] FIG. 22 shows a locking yoke 112 based on the same principle
as in FIG. 21. The locking yoke is operated by a knob 115 with an
inclined contact surface against the outer rod.
[0088] FIGS. 23 and 24 show the outer rod of a section with
integrated locking element 103. The inner rod is pressed against
the locking surfaces by the inclined contact surface of the
operating knob 115 via recesses 113 in the outer rod.
[0089] FIG. 25 shows the contact surface of the knob 115.
[0090] FIGS. 26-28 show an outer rod 102 with integrated locking
elements 103.
[0091] FIG. 29 shows how the locking elements 103 can be
pressed/embossed directly in the outer rod or shaped as separate
elements 104 in a different material, e.g. rubber which can be
inserted into grooves punched out in the outer rod.
[0092] FIGS. 30-32 show an outer rod with a part 104 having flaps
105 punched out. Locking elements 103 are pressed into these and
operating holes punched out.
[0093] FIGS. 33-35 show a locking device with outer rod 102 as
shown in FIGS. 30-32, an inner rod 1 and an operating member 108
with lever 117. The operating member 108 is provided with two pins
109 operating in holes 106. The pins 109 are located on one flange
116 of the member 108. On the opposite flange is a guide pin 110
that operates in a guide hole in the outer rod. A compression
spring 111 is tensioned between the outer rod 2 and the lever 117.
The operating member 108 is moved in the direction of the arrow A,
whereupon the flaps 105 are drawn towards each other by the pins
109 and the locking elements 103 are pushed in tangential direction
towards the inner rod which is thus clamped with considerable
force. The lock is opened by pressing the lever 117 of the locking
device towards the outer rod.
[0094] FIGS. 36-38 show an alternative embodiment of the device
illustrated in FIGS. 33-35. In FIG. 36 the operating member is in
unlocked position and the inner rod 1 can move freely in relation
to the outer rod 102. The operating member 108 is connected as
above to the outer rod 102 via pins acting in operating holes. When
the lever 117 of the operating member 108 is pressed in the
direction of the arrow A, the inner rod 1 is clamped tightly in the
same way as above. Operation of the blocking member 120 blocks the
operating member in locked position. The blocking member comprises
a catch 121 and spring flaps 123, one of each side of the outer
rod, which are attached on a tubular part 124 surrounding the outer
rod. The blocking member 120 also comprises an operating lever 122.
The blocking member, like the operating member, is suitably
manufactured from injection-moulded reinforced plastic. A spring
function is thus easily achieved in the flaps 123. This blocking
member many be designed in many ways. It may, for instance, be
provided with several catches permitting selection of the desired
locking force. However, it is desirable for a locked position to
give sufficient locking force regardless of normal variations in
rod dimensions. This is enabled by the elasticity of the punched
flaps 105 so that a certain resilience arises that prevents any
variations in rod dimensions from affecting the locking function.
The lock is easily opened by pressing the operating lever 122 in
the direction of the arrow B. This embodiment has the advantage of
requiring little space in its normal, locked position since the
operating lever 108 is pressed against the outer rod.
[0095] FIGS. 39-46 show preferred embodiments of components of the
invention, in which, FIG. 39 illustrates a locking member seen from
the front, FIG. 40 illustrates the locking member in accordance
with FIG. 39 seen in perspective, FIG. 41 illustrates a
cross-section through the locking member in accordance with FIG. 39
along the line A-A, FIG. 42 illustrates a wedge seen from the
front, FIG. 43 illustrates the wedge in accordance with FIG. 42
seen in perspective, FIG. 44 illustrates a cap seen in perspective,
FIG. 45 illustrates locking member, wedge, the cap in section, and
actuating member when assembled, FIG. 46 illustrates operating
member, actuating member and wedge, with the operating member in
section.
[0096] The function of the embodiment of the locking member 4 in
FIGS. 39, 40 and 41 is particularly good. The upper part comprises
an attachment collar 10 as previously. The lower part 8 comprises
two jaws 9, the inner surface of which shall be provided with
friction pads 12 and the outer surface of which constitutes a
support surface for spring elements 11. These components 12 and 11
are not shown in the figures but preferably consist of
self-adhesive rubber sheet and split rings of spring steel,
respectively, as described earlier. It is particularly favourable
for the support surfaces of the jaws 9 for these spring steel rings
11 to be slightly elliptical as shown in FIG. 41 so that the small
axis Q of the ellipse runs through the wedge-shaped groove 13 and
thus through the open part of the steel rings 11. Such a design
allows the pressure from the spring elements 11 to be distributed
uniformly across the circumference and the locking effect is
therefore greater since a greater area of the rubber sheet 12 is
engaged. It is also favourable to have a relatively large wedge
angle in the groove 13 since less of the operating force is then
required to overcome the friction and the degree of efficiency is
therefore greater. However, a larger wedge angle also means that
the length of the wedge will be less since the steel rings 11 must
encompass a larger part of the envelope surface of the jaws in
order to obtain the required locking force. A satisfactory opening
function also requires the separating force from the wedge 14 to be
distributed over as long an axial distance on the jaws 9 as
possible. This problem is solved with an embodiment in which the
separating force is achieved by two or more wedge elements. The
figures show how the groove 13 has been provided with two pairs of
facing wedge surfaces 203 with relatively large wedge angle, so
that the separating force on the jaws 9 is distributed over a
longer axial distance that would have been possible with one wedge
element and one pair of wedge surfaces. A wedge 14 as shown in
FIGS. 42 and 43 is provided on its lower side with two wedge
elements having two pairs of outwardly facing wedge surfaces 204.
These wedge surfaces cooperate with the wedge surfaces 203 of the
groove 13 when the wedge 14 is displaced upwards in axial direction
and extremely good opening function is achieved. FIGS. 42 and 43
also show a nut recess 205 for receiving a square nut and a
helicoidal groove 206, said helicoidal groove 206 running through
the wedge 14 from the nut recess 205 up to the upper wedge element
in axial direction. The helicoidal groove 206 is open at the top in
its lower part of the wedge and open at the bottom in its upper
part. These two grooves 205 and 206 in the wedge 14, together with
a combination of screw and nut, enable the position of the wedge to
be adjusted to suitable engagement with the groove 13 in the
locking member 4, as will be described in more detail below.
[0097] FIG. 44 shows a cap 71 designed to be fitted over the
locking member 4. The main function of the cap 71 is to protect the
locking device with its cooperating parts, but also to give the
construction a better design.
[0098] The cap 71 also has an important function in supporting the
wedge 14 so that it cannot fall out of the groove 13. This is shown
in FIG. 45 where the cap 71 is shown in section, fitted onto the
support rings 212, 213 and 214 of the attachment collar 10. The
inner surface of the cap 71 thus supports the outer surface 207 of
the wedge 14 with a certain clearance so that the wedge 14 can
slide axially in the groove 13 without falling out of the groove.
The advantage of this is that the wedge 14 may have much simpler
geometry since no outwardly facing guide edges 22 as in FIG. 3 are
needed. FIG. 45 shows an actuating member 7 in the form of a steel
tape with a hole in the lower part, passed over a screw 201. The
actuating member 7 is bent over a nut 200, the nut being screwed
onto the screw 201 and fitting partially into the nut recess 205.
The screw 201 is inserted into the groove 206 in the wedge 14 as
described earlier, and rests against an edge in the bottom of the
hole. Turning the screw 201 causes the nut 200 to move in axial
direction since the nut recess 205 and actuating member 7 prevent
the nut from rotating with the screw. The cap 71 is provided with a
hole 202 where a screwdriver can be inserted for adjustment of the
screw 201. This arrangement allows the position of the actuating
member 7 to be easily changed in relation to the wedge and the
wedge 14 can be adjusted to suitable engagement with the groove 13.
For the sake of clarity the washer 72 to be fitted into the groove
17 has not been shown in FIG. 45, nor the inner and outer
elements.
[0099] FIG. 46 shows how the wedge 14 cooperates with the operating
member 5 via the actuating member 7. The operating member, shown in
cross-section, is suspended in a shaft 26 threaded through holes in
the outer element 3. The operating member is partially inserted
into the groove 209 in the outer element. The lower part of the
operating member is provided with a hole for the shaft 26, said
hole defining the centre of rotation. Above the hole the operating
member has a curved, outwardly directed surface 211 with large
radius, for receiving the upper part of the actuating member 7.
This actuating member 7 is provided with a hole in its upper part
for the screw 208 which is screwed into a corresponding hole in the
operating member. To disconnect the lock the gripping surface of
the operating member 5 is pressed against the outer element 3 in
the direction of the arrow J. The screw 208 is thus rotated and the
actuating member 7 is drawn upwards in the direction of the arrow F
so that its upper part is bent over the surface 211. Since this has
a large radius, no damaging bending stresses occur in the actuating
member 7. When the actuating member 7 is drawn in the direction of
the arrow F, the wedge 14 is drawn in the same direction and the
jaws 9 of the locking member 4 are separated due to the action of
the wedge surfaces 204 and the lock is released as described
earlier. By turning the screw 201 the position of the wedge 14 in
relation to the actuating member can be altered in the direction of
the arrow P as described earlier.
[0100] This arrangement with a pulling actuating member is
advantageous since it can be in the form of a thin tape with no
buckling problems. It can also easily be adjusted to a suitable
tension through the above design. An actuating member protruding in
the form of a rod having a cross-section that will withstand
buckling is also possible, or a rod in a supporting groove. This
supporting groove may be integrated with the outer element and
possibly be half-open, with the opening towards the inside or the
outside of the outer element. Such an outer element can easily be
manufactured in the form of an aluminium section.
[0101] However, it is inevitable that a protruding actuating member
7 will require more material and more space, at least with the
preferred types of lock where relatively great forces are
transmitted.
[0102] If shape-dependent lock types are to be used, as in FIG. 18,
for instance, a protruding actuating member might be preferably
since the operating forces may then be considerably lower.
[0103] The embodiments with pulling or pushing actuating members
have in common that the actuating member 7 is displaceable along
the longitudinal axis of the outer element 3.
[0104] It is also possible for the operating force to be
transmitted by the actuating member being turned about a shaft
parallel with the longitudinal axis of the outer element 3. The
actuating member might then be a round rod inserted in a groove in
the outer element, or a pipe between the inner element 1 and the
outer element 3.
[0105] Common to these variants of the invention is that the outer
element 3 is provided at one end with a locking device 4 and an
operating member 5 spaced from the locking device 4 towards the
other end of the outer element.
[0106] While the present invention has been described in accordance
with preferred compositions and embodiments, it is to be understood
that certain substitutions and alterations may be made thereto
without departing from the spirit and scope of the following
claims.
* * * * *