U.S. patent number 3,643,292 [Application Number 04/851,974] was granted by the patent office on 1972-02-22 for automatically interlockable hinge fitting.
Invention is credited to Otto Mayer.
United States Patent |
3,643,292 |
Mayer |
February 22, 1972 |
AUTOMATICALLY INTERLOCKABLE HINGE FITTING
Abstract
A lockable hinge fitting which usually forms part of folding
ladders, reclining chairs, etc., in which a pair of hinge arms are
connected one to the other turnable round a common axis. One hinge
arm carries a spring-loaded locking member which in its operative
position locks the hinge fitting in a desired angular position by
engaging one of a number of recesses circumferentially spaced apart
from each other on the periphery of the other hinge arm. An
unlocking lever is provided to move the locking member into its
inactive position where the locking member is locked by a pawl. The
pawl can be moved into its operative position in which it locks the
locking member in its inactive position by pawl-actuating means
during the movement of the unlocking lever in its unlocking
position. This pawl actuating means is preferably an integral part
of the unlocking lever or the pawl. According to the different
attachments of the hinge fitting, the pawl will either release the
locking member in any subsequent angular position defined by a
recess or only when a suitable pivotable movement of the hinge
fitting is performed. In both cases, the interlocking is performed
automatically.
Inventors: |
Mayer; Otto (D-7067
Pluderhausen, DT) |
Family
ID: |
5702590 |
Appl.
No.: |
04/851,974 |
Filed: |
August 21, 1969 |
Foreign Application Priority Data
|
|
|
|
|
Aug 23, 1968 [DT] |
|
|
P 17 75 524.7 |
|
Current U.S.
Class: |
16/325; 74/527;
74/575 |
Current CPC
Class: |
F16C
11/10 (20130101); A47C 1/026 (20130101); E06C
1/32 (20130101); Y10T 16/540243 (20150115); Y10T
74/20636 (20150115); Y10T 74/2133 (20150115); F16C
2350/00 (20130101) |
Current International
Class: |
A47C
1/026 (20060101); A47C 1/022 (20060101); E06C
1/00 (20060101); E06C 1/32 (20060101); E05d
011/10 () |
Field of
Search: |
;16/144,147 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
108,691 |
|
Jan 1968 |
|
DK |
|
402,312 |
|
Nov 1965 |
|
CH |
|
1,042,290 |
|
Sep 1966 |
|
GB |
|
Primary Examiner: Gilliam; Paul R.
Claims
I claim:
1. An automatically lockable hinge fitting, comprising;
a first hinge arm pivotably mounted about a hinge axis;
a second hinge arm, pivotably mounted about said hinge axis, having
a circular portion concentric with respect to said hinge axis and
at least one recess provided in the peripheral portion thereof;
a movably mounted, spring-loaded locking member carried by said
first hinge arm and slidably guided therein substantially radially
with respect to said hinge axis, said locking member being biased
to engage in an operative position said recess provided in said
second hinge arm and thereby define preferred angular positions of
both of said hinge arms;
an unlocking member, pivotably and coaxially mounted with respect
to said hinge axis and pivotable between a first and second
position, said unlocking member having a cam surface provided
thereon which abuts said locking member and moves said locking
member to an inoperative position in which it is disengaged from
said second hinge arm as said unlocking member is pivoted from its
first to its second position;
a pawl, pivotably and coaxially mounted with respect to said hinge
axis, and movable into and out of engagement with said locking
member when said locking member is situated in its inoperative
position, said pawl being frictionally coupled to said second hinge
arm so as to provide common movement therewith with respect to said
hinge axis, and being bifurcated at its outer end so as to provide
pawl arms at both sides of said locking member and a recess at the
outer end of said pawl, the contour of said recess substantially
conforming in its inner portion to the contour of said locking
member and widening in its outer portion to form a shoulder in the
pawl arm situated on the side of said locking member which is
approached when said unlocking member is pivoted from its first to
its second position, the radial distance between said shoulder and
said hinge axis being longer than the radius of the periphery of
said circular portion of said second hinge arm; and
a pawl abutment member, affixed to said unlocking member and
disposed in the pivotable path of said pawl, for engaging and
moving said pawl into locking engagement with said locking member
whenever said locking member is situated in its inoperative
position, said abutment member engaging said pawl during movement
of said unlocking member from its first to its second position,
a catch pivotably mounted on said first hinge arm engaging one arm
of said pawl, and a cam surface provided on said second hinge arm,
for engaging said catch and pivoting said pawl when said first and
second hinge arms approach 180.degree. alignment, and thereby
aligning said recess provided in said pawl with said locking member
and allowing said locking member to be received by said recess so
as to lock said first and second hinge arms with respect to each
other,
a second pawl, pivotably and coaxially mounted with respect to said
hinge axis and frictionally coupled to said second hinge arm, the
outer end of said second pawl being bifurcated so as to provide
pawl arms at both sides of said locking member and a recess at said
outer end, the contour of said recess substantially conforming in
its inner portion to the contour of said locking member and
widening in its outer portion to form a shoulder in the pawl arm
situated at the side of said locking member which is approached by
said second pawl when said second hinge arm is pivoted, the radial
distance between said shoulder of said second pawl and said hinge
axis being shorter than the radial distance between said shoulder
of said first pawl and said hinge axis, but longer than the radius
of the periphery of said circular portion of said second hinge arm,
said recess in said second pawl being wider than said recess in
said first pawl in the range of said shoulders, said pawl arm of
said second pawl which is opposite said pawl arm provided with said
shoulder being provided with a flank extending from the inner end
of said recess substantially obliquely with respect to the radial
direction about said hinge axis, in order to widen said recess at
its outer portion so that during the movement of said locking
member from its inoperative position to its operative position,
said locking member contacts said flank and pivots said second pawl
into a position suitably aligned with respect to said locking
member, in which aligned position said pawl arm provided with said
flank is moved out of the range of said shoulder which is provided
in said pawl arm of said first pawl.
2. An automatically lockable hinge fitting, comprising;
a first hinge arm pivotably mounted about a hinge axis,
a second hinge arm, pivotably mounted about said hinge axis, having
at least one recess provided in a circular, peripheral portion
thereof,
a movably mounted, spring-loaded locking member, carried by said
first hinge arm, biased to engage in an operative position said
recess provided in said second hinge arm and define thereby
preferred angular positions of both of said hinge arms,
an unlocking member, movably mounted about said hinge axis, and
pivotable between a first and second position, said unlocking
member including a cam surface which abuts said locking member and
moves said locking member into an inoperative position in which it
is disengaged from said second hinge arm as said unlocking member
is pivoted from its first position to its second position, and
a pawl, pivotably mounted on an axle parallel with said hinge axis,
and movable into and out of engagement with said locking member
when said locking member is situated in its inoperative position,
said pawl being frictionally connected with said second hinge arm
for common movement therewith with respect to said hinge axis, and
bifurcated so as to provide pawl arms at both sides of said locking
member and a recess at the outer end of said pawl which cooperates
with said locking member, the contour of said recess substantially
conforming in its inner portion to the contour of said locking
member and widening at its outer portion to form a shoulder on one
of said pawl arms on said pawl, the radial distance between said
shoulder and said hinge axis being longer than the radius of the
periphery of said circular portion of said hinge arm, and a face
cam on the other pawl arm of said pawl, said cam cooperating with
said locking member during movement into its inoperative position
and transmitting movement to said pawl during movement of said
locking member, so that a stop face provided on said pawl is moved
into the path of said locking member,
a second, pivotably mounted pawl, the outer end of which is
bifurcated so as to provide pawl arms at both sides of said locking
member and a recess at the outer end of said second pawl which
cooperates with said locking member, the contour of said recess
substantially conforming in its inner portion to the contour of
said locking member and widening in its outer portion to form a
shoulder at each pawl arm of said second pawl, said recess being
wider than the recess in said first pawl, said shoulder of said
second pawl being disposed on the side of said pawl being disposed
on the side of said pawl corresponding to said shoulder provided on
said first pawl, and said shoulder of said second pawl being
disposed on the side of said first pawl provided with said surface
cam and having a shorter distance from said hinge axis than the
other shoulder of second pawl,
said circular portion of said second hinge arm includes a plurality
of recesses on its periphery, the last one of said recesses having
a lateral edge which is inclined and ascends towards the periphery
of said circular portion, a cam being provided on said periphery at
the point at which said inclined edge ends, the top of which has a
longer distance from said hinge axis on said first shoulder of said
second pawl, said first shoulder and said inclined edge of said
recess being situated at the same side of said second pawl and said
recess, respectively.
Description
The present invention relates to lockable hinges.
More particularly, the present invention relates to an
automatically lockable hinge where a pair of hinge arms are
connected one to the other turnably round a common hinge axis, the
first hinge arm carrying a movably mounted and spring-loaded
locking member which is biased to engage in its operative position
a recess provided in the second hinge arm and to define thereby
preferred angular positions of both said hinge arms, an unlocking
member being movably mounted with respect to said locking member
and being movable between a first and a second position, a cam
surface being provided on said unlocking member, and said locking
member being biased to abut said cam surface which is so formed as
to move said locking member into an inactive position, in which it
is disengaged from said second hinge arm, when said unlocking
member is being moved from its first position into its second
position.
Hinges of this type usually form part of folding ladders,
adjustable supports, reclining chairs, swiveling windows, folding
cots, camping articles, etc.
It is a disadvantage of known hinges of this type that, after
having moved the locking member into its inactive position, the
unlocking member has to be actuated by the operator until the two
hinge arms have been moved into the intended position. After having
reached this position the unlocking member may be released,
whereupon the locking member returns into its operative position
and engages the second hinge arm, thus locking the hinge in its
intended position.
Generally it is an object of the present invention to provide an
improved hinge in which the unlocking member has not to be actuated
during the rotating movement of the two hinge arms, thus enabling a
more comfortable handling of articles equipped with a hinge or with
hinges, and in which the locking member will return automatically
into its operative position when the intended angular adjustment of
the hinge has been reached.
It is another object of the present invention to provide a hinge in
which the unlocking member is positioned adjacent one of the hinge
arms when the hinge is in its locked state, so as to prevent from
accidents caused by unintentional unlocking of the hinge, e.g., by
an unintended step onto the unlocking member of a hinge of a
folding ladder.
An additional object of the present invention is to provide a high
degree of stability of the hinge in its locked position.
According to the invention there is provided a pawl being mounted
movable with respect to said hinge axis and into and out of
engagement with the unlocked locking member respectively, said pawl
being frictionally connected with said second hinge arm for common
movement with respect to said hinge axis, said pawl being
positioned in the path of a pawl-actuating member and being capable
of being moved by said pawl-actuating member into locking
engagement with said locking member when this locking member is
situated in its inactive position, said pawl-actuating member being
connected with said inlocking member at least during the movement
of said unlocking member from its first into its second position to
be move into cooperative engagement with said pawl.
It is a further object of the invention to provide a hinge which
may be adapted to different fields of application in such a way
that it is either pivotable only into the next defined angular
position or into any desired angular position, after having
unlocked the locking member; in the latter case the locking may be
effected by a short counterrotation of the hinge after having
passed the desired angular position.
Especially when installed in ladders or camping cots, there is one
end position of the hinge in which both hinge arms are in a linear
alignment, i.e., including an angle of 180.degree.. If the locking
of both hinge arms can only be effected by a short counterrotation
of the hinge arms by which they are pivoted in the direction from
their widest opened position to their folded position, both hinge
arms must have reached a position in which they include an angle of
more than 180.degree. to reach an angular position of 180.degree.
at the end of the necessary counterrotation. This makes it
necessary to provide an appropriate and unsightly bead or recess
within the outer surface of at least one of the hinge arms.
Therefore, it is a further object of the present invention to
provide means which release the locking member immediately before
the hinge reaches its completely opened end position, thus enabling
a locking of the two hinge arms without any need for a
counterrotation of the hinge arms from a position beyond this
completely opened end position.
With respect to this object of the invention it is a preferred
feature of the present invention that the pawl is provided with at
least one face cam cooperating with said locking member during its
movement into its inactive position, said face cam of the pawl
being adapted to transmit a movement to said pawl during said
movement of the locking member, by which movement of said pawl a
stop face provided on said pawl is moved into the path of said
locking member.
The invention, both as to its construction and its method of
operation, together with additional objects and advantages thereof,
will be best understood from the following description of specific
embodiments thereof when read in connecting with the accompanying
drawings, in which:
FIG. 1 shows side elevations of a foldable ladder provided with
hinges according to the present invention;
FIG. 1a shows the ladder in its folded position,
FIG. 1b shows the ladder as a scaffold bridge,
FIG. 1c shows another form of the ladder and
FIG. 1d shows the ladder in a fourth form;
FIG. 2 is a sectional side view of a hinge according to the present
invention in a first embodiment, locked in its completely opened
end position;
FIG. 3 is a sectional side view of another embodiment of a hinge in
an intermediate position between the folded and the completely
opened position, the locking member being released but not yet in
engagement with the second hinge arm, the control lever shown in
FIG. 2 being omitted to show the other details more clearly;
FIG. 4 is a sectional side view of still another embodiment of a
hinge according to the present invention and in a completely opened
and unlocked position, the unlocking member being in its unlocking
position;
FIG. 5a is a sectional side view of the embodiment shown in FIG. 4,
however in an intermediate position and during a clockwise pivotal
movement of the second hinge arm with respect to the first hinge
arm, i.e., during a folding movement of the hinge;
FIG. 5b shows the locking member and two pawls of the hinge shown
in FIG. 5a, however during a counterclockwise movement of the
second hinge arm with respect to the first hinge arm;
FIG. 6 is a cross section taken along line VI--VI of FIG. 5a;
FIG. 7 is a sectional side view of a further embodiment of a hinge
according to the present invention in a completely opened and
locked position;
FIG. 8 is a sectional side view of the embodiment shown in FIG. 7,
however in its unlocked position;
FIG. 9 shows a sectional side view of the hinge shown in FIG. 8
during a clockwise pivotal movement of the second hinge arm with
respect to the first hinge arm;
FIG. 10 is a sectional side view of a further embodiment of the
present invention in a completely opened and locked position;
FIG. 11 is a sectional side view of a hinge similar to FIG. 10 in a
completely opened and unlocked position without the outer parts of
the hinge;
FIG. 11a shows a pawl with face cams on both sides thereof and in a
position similar to the position of the hinge shown in FIG. 11;
FIG. 12 is a sectional side view of the inner parts of a further
embodiment of a hinge fitting according to the present invention in
a completely opened position, the unlocking member being in its
unlocking position;
FIG. 13 is a sectional side view of the embodiment shown in FIG.
12, the unlocking member being omitted and the hinge being in an
intermediate position, in which the locking member is situated
immediately before its engagement with a recess of the second hinge
arm;
FIG. 14 shows the parts of the hinge shown in FIG. 13 in a position
nearly halfway between the folded and the completely opened
position:
FIG. 15 is a cross section of the hinge shown in FIG. 14 taken
along the axis of the pivot bolt connecting both hinge arms;
FIG. 16 shows a section of a locking member formed without cutting;
and
FIG. 17 shows a front elevation of the locking member seen in the
direction as indicated in FIG. 16 by an arrow XVII.
As far as possible similar parts of the different embodiments are
designated by like reference numerals.
The ladder shown in FIG. 1 comprises several straight beams 1,
adjacent ends of which are interconnected by hinges 2. These hinges
are arranged in such a way that they alternately have to be turned
into their opened position in opposite directions. In their
preferred positions shown in FIG. 1 the hinges can be locked. To
unlock the hinges they are provided with unlocking members 3.
Especially from FIG. 1b it may be seen that the unlocking members 3
of the central hinges are so positioned that in their locked
position they lie adjacent and in parallel with one hinge arm. Thus
it is impossible to unlock the hinge by mistake, e.g., by stepping
onto this unlocking members, as this unlocking members must be
turned away from the hinge arms if the hinge is to be unlocked.
The principle of the present invention will now be explained
firstly by reference to a very simple embodiment of the invention,
shown in FIG. 2.
In FIG. 2 the hinge 2 comprises a first hinge arm 10 and a second
hinge arm 14, both pivotably connected for rotation round a common
axis by a rivetted hinge bolt 12. Both hinge arms 10 and 14 are of
substantially U-shaped cross section, thus forming sidewalls 10a,
10b, and 14a, 14b (See FIG. 6) respectively, in which the rivetted
bolt 12 is mounted, and which enclose the inner parts of the hinge.
The sidewalls 10a, 10b, and 14a, 14b are connected at one edge by
bridge parts 10c and 14c, respectively. The other edges of the
sidewalls 10a, 10b, and 14a, 14b, respectively, are flanged as it
is indicated by reference characters 10d and 14d in FIG. 2, thus
forming a substantially closed hollow section. The sidewalls 10a,
10b, 14a, 14b may be reinforced by reinforcing plates 16
concentrically arranged with respect to bolt 12, and mounted
adjacent the outer or inner surface of these sidewalls.
The sidewalls 14a and 14b and the reinforcing plates 16 of the
second hinge arm 14 are recessed at their periphery 18, the
circumferentially spaced recesses 20 defining a plurality of
angular position in which the hinge may be locked. The opposite
edges of each recess extend substantially in a radial direction
with respect to the axis of bolt 12. The sidewalls 10a and 10b, and
the adjacent reinforcement plates of the first hinge arm 10 are
provided with parallel guides 22a and 22b (as shown in FIG. 6),
which extend radially with respect to bolt 12. A locking member 24
is slidably guided by these guides 22a and 22b. A guide pin 26 is
secured to the locking member 24 and extends through a bore 28
provided in an abutment 30 which is part of the first hinge arm 10.
A compression spring 32 is clamped between the abutment 30 and the
locking member 24.
A special recess 34 which serves to lock the hinge in its
completely folded position is provided with an inclined edge 36
ascending towards the following recess 20. This inclined edge 36
will move the locking member against the action of spring 32 when
the hinge is opened from its initially folded position, so as to
enable locking member 24 to slide along the periphery 18 of the
second hinge arm 14 and the respective reinforcement plate 16.
The sidewalls 14a and 14b of the second hinge arm 14 are positioned
within the space between sidewalls 10a and 10b of the first hinge
arm 10. Between sidewalls 14a and 14b a pawl 38 and a spacing
sleeve 40 are pivotally mounted on bolt 12. The unlocking member 3
is pivotally mounted on spacing sleeve 40. Adjacent locking member
24 the unlocking member 3 is provided with an eccentric cam surface
42 ascending radially with respect to bolt 12 towards an end stop
44. This cam surface is adapted to press locking member 24 against
the action of spring 32 into its inactive position when the
unlocking member 3 is pivoted in a counterclockwise sense. In its
inactive position locking member 24 has left the respective recess
20 which it has been engaging. Between end stop 44 and a bearing
bore 46, by which the unlocking member 3 is mounted on spacing
sleeve 40, the unlocking member is provided with a catch 48
protruding in the path of pawl 38 and adapted to engage pawl 38 and
to turn it in a counterclockwise sense when the unlocking member 3
is pivoted in the same sense.
The outer end of pawl 38 is bifurcated so as to form a recess 54
which is adapted to receive the locking member 24 when the locking
member is engaging one of the recesses 20 or 34 if the pawl is
situated in a suitable position. The contour of recess 54 is
adapted to the contour of locking member 24. By a shoulder 56 the
recess 54 is widened in the form of a step in its outer portion
beyond periphery 18, the shoulder being provided in pawl arm 50
which limits recess 54 in clockwise direction. Thus, this pawl arm
50 has two substantially radially extending flanks 58 and 60, the
inner flank 58 having a smaller distance from the opposed flank 62
of the other pawl arm 52 than the outer flank 60.
When unlocking the hinge by a counterclockwise turn of unlocking
member 3, pawl 38 will be engaged by catch 48 at a moment at which
locking member 24 has already been moved against the action of
spring 32 as far as to enable shoulder 56 to slide into engagement
with the front face 64 of locking member 24 until the outer flank
60 abuts the side face 66 of locking member 24.
The eccentrically ascending slope of cam surface 42 will not cause
any self-locking between this cam surface and locking member 24.
Assuming that during the unlocking of the hinge unlocking member 3
has been turned as far as possible in a counterclockwise sense,
i.e., beyond that position in which pawl 38 is engaged by catch 48,
and that unlocking member 3 will then be released, so locking
member 24 will press against cam surface 42 and will thereby pivot
the unlocking member 3 in a clockwise direction towards its initial
or rest position until the front face 64 of locking member 24 will
abut the shoulder 56 of pawl 38. Although the unlocking member 3 is
now released, the locking member 24 can not return into its
unlocked state and both hinge arms may be pivoted with respect to
each other.
The pawl 38 is pivotably mounted on bolt 12 and is clamped between
spacing sleeve 40 and sidewall 14a of the second hinge arm 14, so
that pawl 38 abuts side wall 14a under axial pressure, thus
providing a frictional connection between pawl 38 and the second
hinge arm 14.
After having released the hinge in the position shown in FIG. 2, a
pivotal movement can only be performed in a folding sense by
turning the second hinge arm 14 in a clockwise direction with
respect to the first hinge arm 10. During this movement pawl 38 is
at first also pivoted in a clockwise sense by the frictional
engagement of the second hinge arm 14 and pawl 38, until flank 62
of pawl arm 52 abuts the side face 68 of locking member 24. In this
position the shoulder 56 has been moved out of engagement with the
front face 64 of the locking member 24 so that this locking member
24 may now advance up to the periphery 18 of the second hinge arm
14, thereby further pivoting the unlocking member 3 towards its
rest position by exerting pressure onto the cam surface 42. If the
pivotal movement of the hinge is continued, a recess 20 will
advance to an alignment with locking member member 24, so that the
locking member can advance into this recess 20 and also into recess
54 of pawl 38, thereby further exerting pressure onto the cam
surface 42 of unlocking member 3 and pivoting it back to its rest
position.
As is obvious, after having unlocked the hinge, a folding pivotal
movement can only be performed between two adjacent recesses 20 (or
34 respectively) as the locking member 24 will engage the next
recess as soon as it comes into alignment with the locking member.
If the hinge is in an intermediate position, when it is unlocked,
and if the hinge is pivoted towards its opened position, i.e., a
counterclockwise pivotal movement of the second hinge arm 14 with
respect to the first hinge arm, pawl 38 abuts the side face 66 of
locking member 24 permanently, due to the frictional engagement of
pawl 38 and the second hinge arm 14. However, pawl 38 can not
participate in the pivotal movement of the second hinge arm.
Therefore shoulder 56 remains in its position engaging the front
face 64 of the locking member so enabling the hinge to be pivoted
across more than one defined hinge position, as the locking member
can not engage one of the recesses 20. When the desired position
has been reached it is necessary to continue the pivotal movement
insignificantly and to then perform a short counterrotation in a
counter clockwise sense by the second hinge arm with respect to the
first hinge arm, thereby turning pawl 38 in the same sense and
moving shoulder 56 out of engagement with the front face 64 of the
locking member 24, so that the locking member may now advance to
the periphery 18 and may snap into a recess 20, if the two hinge
arms 10 and 14 are in suitable alignment (see FIG. 3).
As is obvious from the above, after having unlocked the hinge it
may be pivoted towards its opened position as far as desired
without any possibility for the locking member 24 to snap
unintentionally into a recess 20. Also in its opened position, as
shown in FIG. 2, in which the hinge arms are aligned in a
180.degree. position, the locking member can not snap into its
corresponding recess 20. Without further constructional details it
is necessary to bring both hinge arms into an angular position of
more than 180.degree. and to perform a counterrotation from this
position to release the locking member. The hinge as shown in FIG.
2 has an aesthetically designed and pleasing appearance without any
unsightly recesses or beads in its outer surface. In the completely
opened position of the hinge the bridge parts 10c and 14c form a
continuous outer surface. Due to this latter constructional detail
the hinge can not exceed its 180.degree. position as is possible
with the embodiments of hinges shown in FIGS. 3 to 9, because the
bridge parts of these hinges are provided with recesses or
beads.
The hinge shown in FIG. 2 is provided with a special device which
immediately before both hinge arms reach their aligned, completely
opened end position pivots pawl 38 out of its active position in
which it locks locking member 24 in its inactive position, so as to
enable the locking member 24 to snap into a recess 20 as shown as
the hinge reaches its completely opened position. This special
device comprises a control lever 72 mounted on the first hinge arm
10 for pivotal movement round a pivot axis 70, which lies in
parallel with the pivot axis of the hinge, and an extension 74 of
the pawl arm 50 adapted to cooperate with the aforementioned
control lever 72, and a cam 76 of the second hinge arm 14.
The control lever 72 is biased by a spring 78 in a clockwise sense.
The control lever 72 is provided with two lugs 80 and 82, forming a
recess 84 between these lugs, into which recess the extension 74
protrudes. Biased by the torsion spring 78 the control lever 72
abuts with its shorter lug 82 the outer edge of the extension 74.
If the hinge is pivoted towards its opened position, immediately
before reaching the 180.degree. position the cam 76 abuts the lug
80 of the control lever 72 and turns this control lever 72 against
the action of the torsion spring 78 in a counterclockwise sense
during the further pivotal movement of the hinge, so that the
shorter lug 82 engages the extension 74 and turns the pawl 38 in a
clockwise sense as far as to reach the position shown in FIG. 2,
and thereby enabling the locking member 24 to snap into the recess
20 when the hinge has reached its 180.degree. position.
In FIG. 3 a further embodiment of the present invention is shown,
which is similar to the hinge as viewed in FIG. 2 but is not
provided with the special device for releasing the pawl 38
immediately before the completely opened position will be reached.
This makes it necessary to provide the bridge part 10c with a
recess 10e and to provide the bridge part 14c with a bead 14e,
which, as may be seen from FIG. 4 more clearly, enables a pivotal
movement exceeding the 180.degree. position to be performed.
Referring now to FIGS. 4, 5, and 6, there is shown a hinge, which
gives the possibility of pivoting the hinge, after having it
unlocked, across a plurality of angular positions defined by
recesses 20 either in a clockwise or in a counterclockwise sense,
without any possibility for the locking member 24 to snap into one
of the recesses 20, unless the locking is caused by a short
counterrotation as has been explained above in connection with a
counterclockwise pivotal movement of the second hinge arm 14.
The main difference between this embodiment and the embodiment
shown in FIG. 2, is that the special device for releasing the pawl
38 has been omitted and that a second pawl 86 is pivotally mounted
on bolt 12 between spacing sleeve 40 and the other sidewall 14b of
the second hinge arm 14. This second pawl 86 is also clamped
between its adjacent parts so that it abuts the sidewall 14b under
axial pressure, so as to provide a frictional engagement between
this second pawl 86 and the second hinge arm 14. The outer end of
the second pawl 86 is bifurcated so as to form a recess 88, which
in suitable alignment with the locking member 24 enables locking
member 24 to snap into its operative position. The second pawl 86
is provided with two pawl arms 90 and 92, the pawl arm 92
corresponding with pawl arm 52 of the first pawl 38 being provided
with a shoulder 94, so that a flank 96 of pawl arm 90 is opposed by
an inner flank 98 of the second pawl arm 92 and by an outer flank
100. The distance between flanks 96 and 98 is smaller than the
distance between flank 96 and the outer flank 100 and corresponds
with the distance between the side faces 66 and 68 of locking
member 24. The distance between the outer flank 100 and the opposed
flank 96 is much wider than the distance between flanks 60 and 62
of the first pawl 38. Furthermore, the flank 96 extends obliquely
with respect to the radial direction, so that the recess 88 widens
from its inner portion towards its outer portion. Thus, the locking
member 24 can pivot the pawl 86 in a clockwise direction, when
snapping into its operative position by engaging the oblique flank
96.
In FIGS. 5a and 5b pawl arm 52 of the first pawl 38 has been
omitted to show more clearly the form of the second pawl 86.
Furthermore in FIG. 5b the hinge arms 10 and 14 have been
omitted.
When the unlocking member 3 is actuated the cam surface 42 urges
the locking member 24 into its inactive position. Simultaneously
the first pawl 38 is pivoted by the catch 48 as far as to move
shoulder 56 under the front face 64 of the locking member 24 so as
to lock member 24 in its inactive position. The second pawl 86 will
substantially remain in its position in which recess 88 is in
alignment with the locking member 24. If now the second hinge arm
14 is pivoted in a clockwise sense, as shown in FIG. 5a with
respect to the first hinge arm 10, also both pawls 38 and 86 are
pivoted in the same sense by the second hinge arm 14 which they are
frictionally engaging. Shoulder 94 of the second pawl 86 has
already been moved into the path of the locking member 24 until
flank 100 abuts the side face 68 of the locking member 24 when the
shoulder 56 leaves the range of the locking member 24. When
shoulder 56 has completely left the range of locking member 24, the
latter is only allowed to advance up to shoulder 94, the distance
of which from the pivot axis, i.e., the axis of bolt 12, is less
than the distance between shoulder 56 and that axis, but greater
than the radius of the periphery 18. During further pivotal
movement of the second hinge arm 14 in a clockwise sense, the
second pawl 86 abuts locking member 24 and does not participate in
this further pivotal movement. The first pawl 38 is further pivoted
by the second hinge arm 14 until its flank 62 abuts the side face
68 of locking member 24. To advance locking member 24 into one of
the recesses 20 it is necessary to perform a counterrotation, i.e.,
a rotation in counterclockwise sense. As locking member 24 rests on
shoulder 94, and as the distance between this shoulder 94 and the
pivot axis is less than that between shoulder 56 and that pivot
axis, the first pawl 38 can only be pivoted by the frictional
engagement between the second hinge arm 14 and the first pawl 38
until flank 58 of the first pawl 38 abuts the side face 66 of
locking member 24. The second pawl 86 is pivoted until shoulder 94
has left the range of locking member 24, so that locking member 24
can advance up to the periphery 18, from where it snaps into the
next recess 20 when this comes into suitable alignment with the
locking member. If the second pawl 86 has somewhat exceeded the
suitable angula position, locking member 24 will come into
engagement with the oblique flank 96 and will pivot the second pawl
86 in a clockwise direction, until recess 88 has completely
received the locking member 24.
If the second hinge arm 14 is pivoted with respect to the first
hinge arm 10 in a counterclockwise sense after having unlocked the
hinge fitting (see FIG. 5b), the pawl 38 will remain in its
position, which serves for locking the locking member 24, and the
second pawl 86 will be pivoted in a counterclockwise sense until
the outer end of pawl arm 90 abuts the side face 66 of the locking
member 24. During further pivotal movement in a counterclockwise
direction both the pawls 38 and 86 will abut locking member 24 and
will not participate in the further pivotal movement, and locking
member 24 remains in its inactive position. By a counterrotation in
a clockwise direction shoulder 56 will leave the range of locking
member 24 before the shoulder 94 of the second pawl 86 will reach
the range of the locking member 24. In a similar manner as
explained with respect to FIG. 2 the locking member 24 will advance
to the periphery 18 of the second hinge arm 14 and will snap into
the next recess when the pivotal movement is continued.
To positively obtain a frictional engagement between the pawls 38
and 86 and the second hinge arm 14, both pawls are slightly curved
so as to elastically abut the adjacent sidewalls 14a and 14b,
respectively. However, any other suitable means may be provided to
obtain a frictional connection between the second hinge arm 14 and
the pawls.
The bridgeparts 10c and 14c as viewed in FIG. 5a are somewhat
different from that bridge parts shown in FIG. 4, as the bead 14e'
has a steplike form. Both these constructional details arc
equivalent.
Referring now to FIGS. 7, 8, and 9 there is shown another hinge
which, after having been unlocked, may be pivoted either in a
clockwise or in a counterclockwise direction, and which can be
locked by a short counterrotation. However, in this embodiment the
unlocking member 3' is pivotably mounted on a bolt 110, which is
secured to the first hinge arm 10. Two pawls 112 and 114 are
pivotably mounted on bolt 12. Short extensions 112a and 114a of the
pawls 112 and 114 respectively exceed beyond bolt 12 on the side
opposite to the main portions of the pawls. The unlocking member 3'
is provided with a lever arm 116 having an upright catch 118 near
its free end, which approaches the extensions 112a and 114a during
the unlocking movement of the unlocking member 3', thereby pivoting
both the pawls 112 and 114 into their active position, as viewed in
FIG. 8, in which these pawls are aligned with locking member 24. To
obtain an accurate alignment the lever arm 116 is provided with a
second upright catch 120 and both these catches 118 and 120 are so
positioned that they will engage the edges 112b and 114b of the
pawls 112 and 114 respectively on different sides of the bolt 12.
Thus, a rotational movement of pawls 112 and 114 is prohibited when
these pawls abut the catches 118 and 120.
The end of the first pawl 112 adjacent the locking member 24 is
tapered so that its front face 122 is as broad as the front face 64
of the locking member 24. The front face 122 of the pawl 112 is a
stop which serves for locking the locking member 24 in its inactive
position. The end of the second pawl 114 is bifurcated so as to
form a recess 128 the contour of which corresponds with the contour
of locking member 24. In a greater distance from the hinge axis
than the radius of the periphery 18 the pawl arms 124 and 126 are
provided with shoulders 130 and 132 respectively, which are adapted
to cooperate with the front face 64 of locking member 24. The
distance between the shoulders 130 and 132 and bolt 12 is somewhat
less than the distance between the front face 122 of the first pawl
112 and bolt 12. To limit the pivotal movement of the first pawl
112 in a clockwise direction the outer edge of pawl arm 124 is
provided with a stop 136, which protrudes in the path of the first
pawl 112. The pivotal movement of the second pawl 114 is limited by
the pawl arms 124 and 126 which will abut the locking member
24.
Contrary to the embodiments described above the cam surface 42' of
unlocking member 3' is short and is provided on a lever arm 138
which abuts the spacing sleeve 40 in the rest position of the
unlocking member 3', i.e., when the hinge is locked.
The locked position is viewed in FIG. 7. By pivoting the unlocking
member 3' in a counterclockwise sense the cam surface 42' moves the
locking member 24 against the action of the spring 32 out of its
operative position, in which it engages one of the recesses 20.
Simultaneously the catches 118 and 120 pivot pawl 112 in a
counterclockwise sense so that its stop or front face 122 engages
the front face 64 of the locking member 24, thereby holding the
locking member 24 in its inactive position when the unlocking
member 3' has been released. When the second hinge arm 14 is
pivoted with respect to the first hinge arm in a clockwise
direction, as viewed in FIG. 9, the frictional engagement of pawls
112 and 114 with the second hinge arm 14 will pivot pawl 112 out of
the range of locking member 24 and will simultaneously move
shoulder 132 under the front face 64 of the locking member 24,
thereby still holding locking member 24 in its inactive position,
but in a position a little bit nearer to bolt 12 than before.
Simultaneously the unlocking member 3' has been moved back into its
initial position. During a further pivotal movement of the second
hinge arm 14 in a clockwise direction pawl arm 126 abuts the side
face of locking member 24 and the first pawl 112 abuts stop 136 so
that both pawls can not participate in any further pivotal movement
since locking member 24 still rests on the shoulder 132. By a short
counterrotation of the second hinge arm 14, i.e., in
counterclockwise sense, the second pawl 114 will be pivoted until
locking member 24 leaves the shoulder 132 and is free to advance up
to the periphery 18. The first pawl 112 abuts the side face 66 of
locking member 24 and can not prevent the advancing movement of the
latter. As soon as one of the recesses 20 comes into alignment with
locking member 24 the locking member will snap into its operative
position.
If the second hinge arm 14 is pivoted in a counterclockwise
direction after having been unlocked, pawl 112 will move out of the
range of locking member 24 in the same direction, while the
shoulder 130 will move under the front face 64 of the locking
member 24. Thereby the unlocking member 3' has been moved back into
its initial position. The locking member 24 rests on the shoulder
130 until a counterrotation of the second hinge arm 12, i.e., in
clockwise direction, enables locking member 24 to leave shoulder
130 and to advance up to the periphery 18 and to snap into one of
the recesses 20.
The special device as shown in FIG. 2 which is adapted to release
locking member 24 shortly before the completely opened end position
of the hinge will be reached, needs an additional torsion spring 78
and an additional pin 70. It is therefore a somewhat expensive
detail which may be avoided by the embodiment of a hinge according
to FIGS. 10 to 17.
Referring now to FIGS. 10 and 11 the spacing sleeve 40 is
surrounded by a shorter spacing sleeve 40a on which is pivotably
mounted the unlocking member 3. A pawl 38a is mounted on the sleeve
40 which has a bifurcated end similar to the above described
embodiments. The bifurcated end is provided with a recess 54a to
receive the locking member 24. The pawl arms 140 and 142 of the
pawl 38a have a different form. At one side of the locking member
24 the pawl 38a has a pawl arm 140 which is hooklike and bent
towards locking member 24. The inner flank 144 of this pawl arm 140
forms a surface cam which is adapted to cooperate with locking
member 24 when the latter is moved into its inactive position by
means of the unlocking member 3. The other flank 146 is provided
with a shoulder 148 which divides the flank 146 to form an inner
portion 146a and an outer portion 146b. It can easily be seen from
FIG. 10 that by the form of surface cam 144 the locking member 24
will pivot the pawl 38a in clockwise sense when the locking member
24 is moved into its inactive position, thereby moving the shoulder
148 into alignment with the front face 64 of locking member 24.
After having released the unlocking member 3, under the influence
of the spring 32 which urges the locking member 24 against the cam
surface 42, the unlocking member 3 will return into its initial
position until locking member 24 will abut shoulder 48 as viewed in
FIG. 11.
Assuming that the unlocking has been performed in an intermediate
position of the hinge, the second hinge arm 14 may now be pivoted
either on a clockwise or in a counterclockwise direction with
respect to the first hinge arm 10.
If the second hinge arm 14 is pivoted in a counterclockwise
direction, due to the frictional connection between pawl 38a and
the sidewall 14a of the second hinge arm 14, pawl 38a is also
pivoted in a counterclockwise direction with respect to the first
hinge arm 10 and locking member 24 until the surface cam 144 abuts
the locking member 24, whereby the shoulder 148 leaves the range of
the locking member 24 and releases it, which may now advance
towards bolt 12 until the locking member 24 abuts the periphery 18
of the sidewalls 14a and 14b and the reinforcement plate 16. By
this advancing movement of locking member 24 towards the periphery
18 the locking member 24, which is still abutting the cam surface
42 of the unlocking member 3, has further pivoted the latter
towards its initial position. If the pivotal movement of the second
hinge arm 14 in a counterclockwise direction is continued the next
recess 20 will be aligned with locking member 24 so as to enable
the latter to snap into this recess to lock the hinge in this
angular position.
If the second hinge arm 14 is pivoted in a clockwise sense after
having moved the locking member 24 into its inactive position, the
sidewall 14a will also try to move pawl 38 in the same direction.
However, the flank portion 146b of pawl 38a is abutting the side
face 68 of locking member 24 and can not perform any pivotal
movement in a clockwise direction. Therefore, during the
continuation of the pivotal movement of the second hinge arm 14 in
a clockwise direction the locking member 24 remains in its inactive
position. This state may be changed by counterrotating the second
hinge arm 14 in a counterclockwise direction which, due to the
aforementioned frictional engagement will also move the pawl 38a in
a counterclockwise sense, thereby causing the shoulder 148 to
release locking member 24 which now will advance up to the
periphery 18, and will snap into the next recess 20 when this
recess comes into suitable alignment with the locking member
24.
The embodiment described with reference to FIGS. 10 and 11 makes it
possible to pass several recesses 20 during a pivotal movement of
the hinge from its opened position towards its folded position
without any locking of the hinge. If the hinge is to be locked in a
desired position, a short counterrotation is necessary to release
the locking member 24. However, in the opposite direction i.e.,
from the folded position towards the opened position, the hinge
will be automatically locked in each angular position defined by a
recess 20. As is obvious, this locking takes place at that very
moment at which the hinge reaches an angular position defined by a
recess 20, without any need for a counterrotation. Therefore the
hinge will also be locked in its completely opened end position
without any need for exceeding beyond this end position, so that
this embodiment is an advantage with respect to the additional or
special device shown in FIG. 2.
If a hinge is needed which automatically locks the hinge as soon as
the next defined angular position is reached, pawl 38a has to be
replaced by a pawl 38b, as viewed in FIG. 11a. Pawl 38b is provided
with two surface cams 144' and 144" at both sides of the locking
member 24. Between both surface cams 144' and 144" there is
positioned a radially and outwardly extending projection 150, the
outer end of this projection forming a stop face 148' cooperating
with this front face 64 of the locking member 24. At both sides of
the projection 150 there are provided recesses 154a and 154b
respectively, which are adapted to receive the locking member 24 in
its operative position. As is obvious from FIG. 11a, locking member
24 will either contact the surface cam 144' or the surface cam 144"
during its movement into its inactive position, thereby pivoting
pawl 38b in such a direction that the projection 150 is moved under
the front face 64 of locking member 24, thereby locking the locking
member in its inactive position. If the second hinge arm 14 is now
pivoted with respect to the first hinge arm 10 in one of the
possible directions, pawl 38b is moved so that the projection 150
releases the locking member 24, due to the frictional connection
between pawl 38b and the second hinge arm 14, thereby enabling the
locking member 24 to advance into one of the recesses 154a or 154b
respectively as soon as a recess 20 is in suitable alignment with
the locking member 24.
As has already been mentioned it may be desirable to have a hinge
which gives the possibility of turning the hinge in both directions
across a plurality of recesses 20 without any possibility for the
locking member 24 to lock the hinge unintentionally, but only after
a short counterrotation of the hinge. Such a hinge can be obtained
by adding a second pawl 86a to a hinge as shown in FIGS. 10 and 11.
The second pawl 86a is pivotally mounted on the spacing sleeve 40,
however on the other side of the unlocking lever 3, as can be seen
from FIG. 15. The second pawl 86a is frictionally connected with
sidewall 14b of the second hinge arm 14 so as to be pivotable
together with the second hinge arm. This embodiment is now
explained with reference to FIGS. 12 to 15.
It is to be noted, that a trouble-free function of the hinge does
not demand a positioning of the pawls on different sides of the
unlocking member 3, as has been shown only by way of example. Any
other arrangement is possible, provided that a frictional
engagement of the pawls and the second hinge arm is possible. So it
is possible to secure a friction plate to the second hinge arm 14
for common rotation therewith and to provide a frictional
connection between one pawl or both pawls and this friction plate
while the unlocking member may be situated adjacent one of the
sidewalls 14a or 14b.
The end of the second pawl 86a is bifurcated so as to provide a
recess 88a which is adapted to receive the locking member 24 in its
operative position, as viewed in FIG. 13. The recess 88a is wider
than the distance between the side faces 66 and 68 of locking
member 24. Lateral flanks of recess 88a are provided near its outer
end with steplike shoulders 148a and 148b. The distances of these
shoulders of the second pawl 86a from the pivot axis of the hinge,
i.e., the axis of bolt 12, is such that the shoulder 148a, being
situated on the same side of the recess 88a as shoulder 148 of the
first pawl 38a, has a smaller distance from the periphery 18 of the
second hinge arm 14 than shoulder 148, and that shoulder 148b on
the side of the surface cam 144 of the first pawl 38 is situated
somewhat nearer to the periphery 18 than shoulder 148a. However,
the shoulders 148, 148a, and 148b lie outwards from the periphery
18 of the second hinge arm 14, so as to enable shoulder 148b to
prevent locking the member 24 from engaging one of the recesses 20
of the second hinge arm 14.
In this embodiment the inclined edge 36 of the special recess 34
ends in a cam 35, which protrudes over the circular part of the
periphery 18 of hinge arm 14 in such an extent that the top of the
cam 35 has a somewhat greater distance from the pivot axis than the
second shoulder 148b of the second pawl 86a.
To show this embodiment very clearly unlocking member 3 is only
shown in FIGS. 12 and 15, and not in FIGS. 13 and 14. The position
of the elements of the hinge shown in FIG. 12 corresponds to an
unlocked position in which the unlocking member 3 has been pivoted
in a counterclockwise sense to move locking member 24 into its
inactive position. By engagement between locking member 24 and cam
surface 144 the first pawl 38a has been moved in a clockwise
direction and the shoulder 148 has been moved under the front face
of locking member 24 to lock the locking member in its inactive
position.
As in its operative position locking member 24 was within recess
88a or the second pawl 86a and as this second pawl is not moved
during the unlocking movement of unlocking member 3, locking member
24, and the first pawl 38a, the second pawl 86a will remain in its
position shown in FIG. 12, the hinge remains in its unlocked
position and may, if this is an intermediate position, be pivoted
in either direction.
If the second hinge arm 14 is pivoted with respect to the first
hinge arm 10 in a counterclockwise direction both pawls 38a and 86a
will be pivoted in the same direction, and thereby at first the
second shoulder 148b of the second pawl 86a will move under locking
member 24, and then the shoulder 148 of the first pawl 38a will
release the locking member to advance towards shoulder 148b, and
finally pawl arm 140 of the first pawl 38a and the corresponding
pawl arm 90a of the second pawl 86a will abut the side face 66 of
locking member 24, thereby preventing both pawls 38a and 86a from
any further movement. In this position the pivotal movement of the
second hinge arm 14 may be continued without any locking movement
of locking movement 24. The locking of the hinge can only be
effected when the second hinge arm 14 performs a short
counterrotation in a clockwise direction, as such a pivotal
movement will pivot both pawls 38a and 86a only so far that the
flanks of the recesses 54a and 88 adjacent shoulders 148 and 148a
respectively abut the side face of locking member 24 due to the
fact that locking member 24 has already been advanced up to the
shoulder 148b which lied closer to the periphery 18 than shoulders
148 and 148a. However, the pivotal movement of both pawls is
sufficient to release the locking member 24 from the shoulder 148b
so that locking member 24 may advance up to the periphery 18 from
where it will snap into the next recess 20 coming into suitable
alignment. In FIG. 14 is shown the position of the elements of the
hinge during a pivotal movement of the second hinge arm 14 in a
counterclockwise direction and before the counterrotation has
begun.
If the hinge is unlocked and the second hinge arm 14 is pivoted in
a clockwise direction with report to the first hinge arm 10 the
second pawl 86a is also pivoted in a clockwise direction until the
outer flank portion of recess 88a abuts the side face 68 of the
locking member 24, thereby bringing the shoulder 148a into the path
of the locking member 24. As already has been mentioned the locking
member 24 rests on the shoulder 148 since the unlocking movement
has been finished. If the pivotal movement of the second hinge arm
14 in a clockwise direction is continued the elements remain in
their respective positions and there is no possibility for the
locking member 24 to snap into one of the recesses 20. When a short
counterrotation in counterclockwise direction is performed, the
pawls 38a and 86a are pivoted in the same direction, so that the
shoulder 148 releases the locking number 24 before the second
shoulder 148b of the second pawl 86a comes into the path of locking
member 24. This enables locking member 24 to advance up to the
periphery 18 of the second hinge arm 14, from where it will snap
into the next recess 20 which comes into suitable alignment. To
insure that the shoulder 148b will not hinder the advancing
movement of locking member 24 towards the periphery 18, recess 88a
of the second pawl 86a is preferably wider than the corresponding
contour of the locking member 24.
If the hinge is in its completely folded position, locking member
24 engages the special recess 34. If the hinge is opened from this
folded position, locking member 24 slides along the inclined edge
36 until it reaches the top of cam 35. Thereby the locking member
24 has been lifted to such an extent that the second shoulder 148b
of the second pawl 86a can be moved under the front face 64 of the
locking member 24, thereby holding the locking member 24 in its
inactive position, so that a continuation of the pivotal movement
of the hinge can not be interrupted by the locking member 24 until
a short counterrotation is performed, which will enable the locking
member 24 to engage one of the recesses 20.
In order to make the frictional connection between the pawls and
the sidewalls 14a and 14b respectively of the second hinge arm 14
as much as possible independent from the tensile stress within bolt
12, the pawls 38a and 86a are mounted on a spacing sleeve extending
between the reinforcement plates. Since the unlocking member 3 is
mounted on a shorter sleeve 40a surrounding the spacing sleeve 40,
the unlocking member is mounted between both pawls 86a and 38a.
In some applications of the improved hinge according to the present
invention, e.g., adjustable head rests in automobiles, adjustable
telephone swivel arms, or more generally, hinges with an axially
branching arm which is pivotable around 360.degree. , etc., it is
of advantage if the unlocking member 3 is not mounted on bolt 12
but on the first hinge arm 10, as bolt 12 is not within the normal
range of the hand of the operating person. The unlocking member 3
may be formed as a one or a double armed hand lever which is
connected with the locking member 24 or an extension thereof, e.g.,
the guide pin 26, by a linkage, cable, Bowden cable, etc.
Especially the embodiments shown in FIGS. 10 to 15 make it possible
to produce hinges by a simple mass production without expensive
cutting operations. Therefore it is an advantage if the locking
member 24 is also manufactured without a cutting operation. The
locking member as shown in FIGS. 16 and 17 is made from coiled
stock by punching and is the bent in form of an oblong ring. An
upset pin 26 can simultaneously with this bending step be secured
to the locking member by pressing. By this method favorable radii
may be obtained at 24b, 24c, and 24d, which hitherto have been
machined by cutting operations. These radii are important with
respect to the engagement between the locking member, the guide for
the locking member in hinge arm 10, and the several recesses which
are adapted to receive the locking member.
The proposed form of the locking member 24 enables the production
of a universally applicable, unexpensive, and reliable hinge.
It is to be noted that hinges according to the present invention
are especially advantageous in constructions where a number of
hinges have to be pivoted simultaneously, since after having
actuated the unlocking members of the hinges the hinges can be
adjusted at least in the next hinge position without any need for a
continued actuating of the unlocking members.
The embodiments shown in FIGS. 4 to 6, 7 to 9, and 12 to 15 can be
provided with a torsion spring which biases the hinge arms 10 and
14 into their folded position. This is advantageous especially in
reclining seats for automobiles and it makes it possible to adjust
the hinge on both sides of the seat by reclining or by performing a
movement of the body in opposite direction when an unlocking member
on one side of the seat has been actuated which is also connected
to the unlocking member of the hinge at the other side of the
reclining seat. Thus, it is possible to actuate the unlocking
member for a very short period by one hand and then to adjust the
reclining seat without any necessity of taking off the hands from
the steering wheel.
If coaxially aligned hinges are used in pairs the bolts 110 (see
FIGS. 7 to 9) can be made in the form of a connecting rod which may
be connected rigidly between the unlocking members 3' and which may
serve as a step when the hinges are attached to ladders. In this
case preferably only one unlocking member is provided with a
handle. Furthermore, this connecting rod may be enclosed by a
protective tube.
Bolt 12 may be divided in a radial plane and may be formed as a
tubular rivet on opposite sides of the hinges. The connecting rod
which is rigidly connected between the unlocking members of both
hinges may be mounted within the bores of the tubular rivets.
However, it is also possible to form the tubular rivets of the
coaxially aligned hinges as one single connecting tube so that a
rod connecting the unlocking members of both hinges may be mounted
within this connecting tube.
* * * * *