This invention relates to baby strollers, and more particularly, to baby strollers designed for selective use on hard surfaces such as floors and sidewalks and also on soft surfaces such as sand, bare dirt, and grass.
U.S. Pat. No. 5,158,319 entitled ALL TERRAIN BABY CARRIAGE, issued Oct. 27, 1992 to Barbara and James Norcia, hereby incorporated herein by reference, discloses a carriage or stroller with selectively usable rollers for soft surfaces and conventional wheels for hard surfaces and represents a significant advance in the art. The rollers of the patent however, are provided with gear like ribs found to be unnecessary and in fact detrimental in collecting dirt, grass and other debris in use. Provision of the gear like ribs also adds significantly to manufacturing cost. Further, a hand operated mechanism for raising and lowering the wheels which elevate at least one roller can be unecessarily complex, unwieldy and awkward in use.
In view of the foregoing, it is the general object of the present invention to provide an improved all terrain stroller eliminating the gear like ribs on the rollers and substituting a simple yet effective and easy to operate foot pressure mechanism for raising and lowering the wheels which convert from hard to soft surface operation.
In fulfillment of the aforementioned object and in accordance with the present invention, an all terrain stroller is provided with front, rear and intermediate frame members, a seat for supporting a baby, a wheel assembly including at least one and preferably a pair of vertically movable wheels for selective travel over hard and soft surfaces, at least two transversely extending smooth surface rollers respectively mounted on said front and rear frame members for efficient travel over soft terrain, the aforesaid wheels projecting slightly below one of said rollers in their lower position whereby to elevate the roller above a hard surface, and a lever mechanism operable by foot pressure to raise and lower said wheels.
The stroller is also provided with a handle for pushing the same and the handle and all frame members are hingedly interconnected to permit the stroller to collapse for storage.
A pair of wheels mounted respectively at opposite ends of the roller on the front frame member are operable in both modes i.e, hard and soft surface operation. The are preferably approximately one inch larger in diameter than the roller.
Referring particularly to
Front and rear rollers 20 and 22 have smooth easily maintained surfaces throughout and are particularly well adapted to use on soft and irregular surfaces due to their large diameter and particularly their substantial length.
Intermediate the rollers 20,22, a wheel assembly indicated generally at 24 includes a pair of transversely spaced wheels 28,28 which are mounted on a transverse bracket member 30 supported at opposite ends by short arms 32,32 for ease in steering the stroller. Links 33,33 fix the arms 32,32 to a pivot shaft 34 which extends transversely and which has a double ended lever 36 fixed thereto and exposed at one end for convenient operation by the foot of an adult using the stroller. The shaft 34 is pivotally mounted at opposite ends in brackets 35,35 in turn supported by a front frame member 62. As will be obvious, foot pressure on the lever 36 will cause the shaft 34 to pivot and swing the arms 32,32 and bracket member 30 in one and an opposite direction raising and lowering the wheels 28,28. The bracket and wheels are biased toward their upper position by a spring 38 and a latch element 40,
Left and right hand front frame members 62,62 also support the aforementioned roller 20 on a shaft 60 carried at opposite ends by transversely spaced lower portions of the frame members. Left and right hand Intermediate frame members 44,44 also have front end portions hingedly connected to a front frame member. The members are in two sections hingedly interconnected with rear sections hingedly connected to the rear frame members 66,66. The handle 14 is also hingedly connected to the rear frame members so that the entire stroller is completely collapsible for storage.
In accordance with another aspect of the invention, a pair of wheels 52,52 are mounted coaxially with the rear roller 22 on a shaft 54 as best seen in
From the foregoing it will be apparent that the general object set forth above has been fully satisfied and an improved all terrain stroller both efficient in use and durable over a long service life has been provided. Further, the stroller can be manufactured at economic advantage.