BACKGROUND
OF
THE
INVENTION
The present invention relates to a
folding joint for a foldable play yard, and more
particularly to a safety folding joint which
prohibits the frame rods of the foldable play yard
from being forced to collapse by an error, so that
children can play in the foldable play yard safely.
Conventional play yards, in which
infants can be left to play, crawl, are commonly
not collapsible, therefore they need much storage
space when not in use. Recently, a variety of
foldable play yards have been disclosed, and have
appeared on the market. Because the frame
structures of regular foldable play yards are made
foldable by means of the operation of folding
joints, they tend to be forced to collapse when
infants play with the folding rails. If the frame
structure of a foldable play yard is suddenly
folded up by an error, infants may be jammed in the
collapsed frame structure. U.S. Pat. No. 4,934,025
discloses an improved hinge for foldable play
yards. The hinge comprises mating first and second
halves, each half with an axial bore adapted to
receive members to be pivoted with the hinge, an
offset portion formed in each hinge half with a
pivot pin extending centrally therethrough, the
mating halves adapted to be pivoted about the axis
of the pivot pin which is perpendicularly to, but
offset from the axes of the bores, interference
member located on the hinge halves to limit the
degree of pivoting of the hinge halves with respect
to each other, circumferential slots extending
through the surface of each hinge half for
receiving a radially projecting ring securable to
the received members to guide the rotational motion
of the hinge with respect to the rings and received
members. The ring is formed with ratchet teeth
cooperable with ratchet teeth in the adjacent hinge
half for securing the hinge in a locked or unlocked
rotational orientation. This structure of hinge
still has drawbacks. One drawing of this structure
of hinge is that the ratchet teeth of the hinge
wear quickly with use. Another drawback of this
structure of hinge is that the upper part of the
hinge tends to be forced to deform when the rails
are extended out, because only one pivot pin is
provided to support the hinge halves, Furthermore,
because the two rails are hinged together, they
will make a scissors action when they are forced
hinge halves are forced to collapse, and infants
tend to be jammed in the rails. U.S. Pat. No.
5,211,498 discloses a folding joint for a foldable
play yard which is an invention of the present
inventor, including a base frame having two
connecting members pivotably secured at the inside
for holding two rails permitting them to be held in
a longitudinally aligned position or folded up into
a collapsed position. The connecting members each
have an axial hole at one end for receiving either
rail, two through holes on two opposite side walls
thereof, and a tract connected between the two
through holes. The rails each have a pivot hole
secured between the two through holes by a headed
pin. The two rails are held in the longitudinally
aligned position when the head of the headed pin is
engaged in one through hole; and the two rails are
allowed to be folded up when the head of the headed
pin is rotated to the other through hole. This
structure of folding joint is functional, however
when infants play with the rails, the rails may be
forced to collapse, causing an accident to occur.
SUMMARY
OF
THE
INVENTION
The present invention has been
accomplished to provide a folding joint for a
foldable play yard which eliminates the aforesaid
drawbacks. According to the preferred embodiment
of the present invention, the safety folding joint
comprises a control member, two locating blocks
respectively pivoted to the control member and
coupled to and turned about two frame rods of a
rail of the foldable play yard, and two locking
sockets respectively, longitudinally slidably
mounted around the frame rods and forced by spring
means into engagement with the locating blocks to
lock the folding frame rods in a longitudinally
aligned position. When the locking sockets are
respectively and axially moved backwards and
disengaged from the locating blocks, the control
member is allowed to be turned relative to the
frame rods from a locking position to an unlocking
position, and therefore the frame rods are allowed
to be folded up.
BRIEF
DESCRIPTION
OF
THE
DRAWINGS
Fig. 1 is an exploded view of a folding
joint according to the present invention;
Fig. 2 is a bottom view of a locking
socket according to the present invention;
Fig. 3 is a sectional view of the
folding joint when set in the operative position
according to the present invention;
Fig. 4 is similar to Figure 3 but
showing the locking sockets unlocked;
Fig. 5 is similar to Figure 4 but
showing the control member and the locating blocks
turned through 180x angle relative to the frame
rods;
Fig. 6 is a sectional view of the
present invention, showing the folding joint folded
up;
Fig. 7 is a sectional view taken along
line VII-VII of Figure 3;
Fig. 8 is a sectional view taken along
line VIII-VIII of Figure 5; and
Fig. 9 is an applied view of the present
invention, showing the folding joint installed in
one rail of a foldable play yard.
DETAILED
DESCRIPTION
OF
THE
PREFERRED
EMBODIMENT
Referring to Figures 1 and 9, a safety
folding joint 1 in accordance with the present
invention, is adapted for use in a foldable play
yard to connect two frame rods of a folding frame
rod together, comprised of a control member 11, a
pair of locating blocks 2 respectively pivoted to
the control member 11 at two opposite sides, two
frame rods 4 respectively coupled to the locating
blocks 2, and two locking sockets 3 respectively
mounted around the frame rods 4. Because the
locating blocks 2, the locking sockets 3 and the
frame rods 4 are symmetrically connected to the
control member 11 at two opposite sides, the
structure and function of the folding joint 1 can
be understood from the following description.
Referring to Figures 2 and 3, and Figure
1 again, the control member 11 is a hollow member
adapted for holding one end of the locating block 2
on the inside. The locating block 2 comprises a
longitudinal through hole 24, a transverse through
hole 22 in the middle, a transverse pivot hole 21
near one end in parallel to the transverse through
hole 22, a projecting rod 25 longitudinally
extended from one end remote from the transverse
pivot hole 21, and a guide groove 23 inside the
longitudinal through hole 24 and extended between
two opposite ends of the transverse through hole
22. The locking socket 3 comprises a longitudinal
through hole 32, two longitudinal sliding grooves
33 bilaterally disposed in communication with the
longitudinal through hole 32, an outside annular
flange 31 raised around the periphery at one end,
an inside annular flange 37 raised around the
inside wall corresponding to the outside annular
flange 31 (see Figure 3), and a notch 34 disposed
at the outside annular flange 37 and adapted for
coupling to the projecting rod 25 of the locating
block 2. A spring 35 is mounted in the
longitudinal through hole 32 of the locking socket
3, and stopped at the inside annular flange 37.
The frame rod 4 comprises a front extension tube 41
mounted with a washer ring 36, a first transverse
pin hole 44 at one end of the front extension tube
41, and a second transverse pin hole 45 adjacent to
the front extension tube 41 and remote from the
first transverse pin hole 44.
Referring to Figures 1 and 3 again, the
front extension tube 41 of the frame rod 4 is
inserted through the longitudinal through hole 32
of the locking socket 3 into the locating block 2,
and then coupled thereto by inserting a locating
pin 42 into the transverse through hole 22 of the
locating block 2 and the first pin hole 44 of the
frame rod 4. Before coupling the frame rod 4 to the
locating block 2, a locating pin 43 is mounted in
the second transverse pin hole 45 of the frame rod
4. The length of the locating pin 43 is longer than
the outer diameter of the frame rod 4. Therefore,
when the locating pin 43 is mounted in the second
transverse pin hole 45 of the frame rod 4, the two
opposite ends of the locating pin 43 project out of
the periphery of the frame rod 4. When the frame
rod 4 is inserted through the longitudinal through
hole 32 of the locking socket 3, the two opposite
ends of the locating pin 43 are respectively
inserted into the longitudinal sliding grooves 33
of the locking socket 3 and moved therein.
Therefore, the locking socket 3 is prohibited from
rotary motion relative to the frame rod 4. Further,
the pivot hole 21 of the locating block 2 is
pivotably connected to the control member 11 by a
pivot 12. When assembled, the frame rod 4 with the
locating pin 42 can be turned within the locating
block 2 along the guide groove 23 between two
reversed positions (see Figures 7 and 8). However,
because one end of the locating pin 42 is moved in
the guide groove 23, the frame rod 4 is prohibited
from escaping out of the locating block 2.
Referring to Figures 4, 5, and 6, the
spring 35 imparts a forward pressure to the locking
socket 3, causing the notch 34 of the outward
annular flange 31 of the locking socket 3 to be
forced into engagement with the projecting rod 25
of the locating block 2, and therefore the locating
block 2 is constrained by the locking socket 3 and
the frame rod 4 and unable to be folded up. When
the locking socket 3 is pulled backwards to
compress the spring 35 and to disengage the notch
34 from the projecting rod 25 of the locating block
2 (see Figure 4), the control member 11 and the
locating block 2 can then be turned through 180°
angle relative to the locking socket 3 and the
frame rod 4 (see Figure 5), for permitting the
safety folding joint to be folded up (see Figure
6).