Foldable baby carriage with security lock

A foldable carriage with security lock includes a plurality of members which are pivotally connected to each other and can be folded from an open to a closed position. One of the members includes a pivotally mounted latch which can engage a pin on another one of the members to hold the carriage in its open unfolded position. The latch is provided with a locking element which engages the other member so that the latch cannot be rotated to disengage the pin, unless the locking element is purposely retracted.

FIELD AND BACKGROUND OF THE INVENTION 
The present invention relates in general to baby carriages or strollers, 
and in particular to a new and useful carriage which includes a foldable 
frame and a security lock for preventing inadvertant folding of the frame. 
Strollers or baby carriages are known which have foldable frames of various 
configurations which are capable of being folded into a smaller size for 
easy carrying. 
A latch of some sort is usually provided which holds the baby carriage in 
its open or unfolded position. This latch can be activated or released to 
permit folding of the carriage frame. By design or after repeated use, it 
becomes increasingly easier to fold the baby carriage into its closed or 
folded configuration. An accidental movement of the latch may thus result 
in an undesired folding of the carriage, when for example an infant is 
sitting in the carriage. 
SUMMARY OF THE INVENTION 
The present invention is directed to a security lock for a baby carriage 
having a foldable frame which requires the purposeful unlocking of the 
latch before it can be moved to permit folding of the carriage frame. 
Accordingly, an object of the present invention is to provide a carriage 
having a foldable frame and lock combination which comprises a first frame 
member, a second frame member, a cross member pivotally connected to the 
first and second frame members, the first, second and cross members being 
moved between an open and a closed position. In the open position the 
first and second frame members are spaced from each other. In the closed 
position, which requires movement of the cross member in a closing 
direction, the first and second frame members are positioned adjacent each 
other to reduce the overall volume of the carriage. A latch is pivotally 
connected to the first or cross member with a latch engagement means 
connected to the other of the first and cross members that is engaged with 
the latch to hold the carriage in its open position. With movement of the 
latch to disengage it from its engagement means, the frame may be folded 
into its closed position. In the open position, the first and cross 
members both have portions which are adjacent each other. The latch and 
latch engagement means are connected to these adjacent portions of the 
first and cross member. A locking element is movably mounted to the latch 
from a first position which engages the mentioned portion of the first or 
cross member, and a second position which is disengaged from that portion. 
Biasing means are provided for biasing the locking element into its first 
or engaging position. An actuator is also provided for moving the locking 
element into its second position. The actuator has a quasi-stable position 
when it has disengaged the locking element from the mentioned portion so 
that any abrupt motion or an appropriate engagement of the actuator with a 
selected frame member will cause the locking element to return to its 
first position so that it is ready to reengage the first or cross members 
when the carriage is unfolded into its open position. 
A further object of the invention is to provide a carriage and security 
lock combination which is simple in design, rugged in construction and 
economical to manufacture. 
The various features of novelty which characterize the invention are 
pointed out with particularity in the claims annexed to and forming a part 
of this disclosure. For a better understanding of the invention, its 
operating advantages and specific objects attained by its uses, reference 
is made to the accompanying drawings and descriptive matter in which a 
preferred embodiment of the invention is illustrated.

Referring to the drawings in particular, a carriage having a foldable frame 
of the type utilized in the invention is shown in FIG. 1. The carriage 
frame 10 which is foldable supports a seat shown in phantom line having a 
back 14 supported by a first frame member 16 and a seat with sides 12 
supported by a pair of arm members 32 (one of which is shown) on either 
side of the carriage frame 10. A second frame member 18 is pivotally 
mounted to the two arms 32 at pivot point 36. Frame members 16 and 18 are 
both U-shaped so that they have one leg on each side of the carriage 
frame. The lower end of each leg of second frame member 18 rotatably 
receives an axle of a pair of rear wheels 22. 
The two legs of first frame member 16 are pivotally connected to an 
opposite end of each arm member 32 at pivot point 38. 
A cross member 20, 26 is pivotally mounted at pivot points 40 and 42 
between first and second members 16 and 18. The cross member is itself 
foldable at pivot point 44 and formed of a cross link 20 and a connecting 
link 26. 
The carriage frame 10 is a front frame member 34 which is pivotally mounted 
at 48 to second frame member 18 and pivotally mounted at 46 to link 26. 
The carriage frame includes two front frame members 34, one on each side 
of the frame, each of which pivotally and rotatably carries one or more 
front steering wheels 24. 
The U-shaped first frame member 16 carries at its top a handle 28 and the 
second U-shaped frame member 18 carries at its top a padded cross rail 30. 
Pivotally mounted to the lower end of first frame member 16 is a latch 50 
having an actuator bar 52 which extends across the width of carriage frame 
10. Two links 50 are provided, one for each leg of frame member 16, and 
bar 52 is connected to both of these links. 
Link 50 includes a recess or hook 56 shown in greater detail in FIGS. 2 and 
3, which hooks latch engagement means in the form of pin 54 to hold the 
frame in its open or unfolded position shown in FIG. 1. 
A spring 58 is connected between latch 50 and member 16 to hold hook 56 
into engagement with pin 54. 
When latch 50 is rotated in the direction of arrow 60 the carriage frame 
can be moved into its closed position. To accomplish this first frame 
member 16 is rotated counterclockwise with respect to pivot point 38 and 
42. Second frame member 18 rotates clockwise with respect to pivot points 
36 and 40. Front frame member 34 rotates in the direction of arrow 62 and 
the cross and connecting links 20 and 26 rotate with respect to pivot 
point 44 toward each other. In the folded or closed position of carriage 
frame 10, members 16, 18 and 34 lie substantially parallel and adjacent 
each other to form a very compact configuration. 
To prevent the inadvertant disengagement of latch 50 from pin 54, and in 
accordance with the invention, a security lock illustrated best in FIGS. 
4, 5 and 6 is provided. 
The security lock includes a locking member comprising a pin 64 which is 
movably mounted on the latch 50. In the latched and locked position as 
shown in FIG. 4, pin 64 extends over cross link 20 to prevent its movement 
in a closing direction for closing the frame. This movement is normal and 
up away from the page in FIG. 4. The engagement of pin 64 over the top of 
cross link 20 also prevents the rotation of link 50 in the direction of 
arrow 60. 
To permit folding of the carriage frame, an actuator head 67 which is fixed 
to pin 65 is rotated with the aid of an actuator arm 68 into the position 
shown in FIG. 5. This causes the withdrawal or retraction of pin 65 away 
from link 20 and into its sleeve 70. As best shown in FIG. 6, sleeve 70 
and actuator head 67 are both provided with beveled surfaces 72 and 74. 
Upon relative rotation of actuator head 67 with respect to sleeve 70, pin 
65 is pulled to the right. Pin 65 includes a stem 76 which is fixed in a 
bore 78 of actuator head 67. Biasing means in the form of spring 80 is 
engaged around stem 76 and seated in recess 82 of sleeve 70 to bias pin 65 
into its first engaging position shown in FIG. 4. The rotation of actuator 
head 67 with arm 68 acts against the bias of spring 80 through the aid of 
beveled surfaces 72, 74. 
When in the position shown in FIG. 5, flat stop surfaces 84 and 86 of 
beveled surfaces 72 and 74 engage each other. This establishes a 
quasi-stable position for the actuator head and arm. Any slight rotation 
of arm 68 dislodges surfaces 84 and 86 from each other and, due to the 
bias of spring 80, snaps pin 65 back to its first engaging position. This 
dislodging of the actuator from its quasi-stable position can be achieved 
either due to any abrupt motion of the carriage either when it is unfolded 
or folded due to the inertia of arm 68. 
A more positive release of pin 65 is achieved by selecting the length of 
arm 68, as shown in FIG. 2, to engage first frame member 16 after latch 50 
has been rotated sufficiently to disengage hook 56 from pin 54. With this 
engagement arm 68 rotates sufficiently to disengage stop surfaces 84, 86 
from each other and return the locking member to its first engaging 
position. Since the carriage is moving into its unfolded position, 
however, the latch does not yet engage the cross link 20. To permit 
engagement of pin 65 over cross link 20, pin 65 is provided with a beveled 
surface 88, facing link 20. 
While a specific embodiment of the invention has been shown and described 
in detail to illustrate the application of the principles of the 
invention, it will be understood that the invention may be embodied 
otherwise without departing from such principles.