Land vehicles – Wheeled – Tiltable vehicles – stabilized by attendant or article
Reexamination Certificate
2000-07-07
2002-11-05
Walsh, Donald P. (Department: 3611)
Land vehicles
Wheeled
Tiltable vehicles, stabilized by attendant or article
C280S030000, C280S047210, C280S047240, C182S016000, C182S021000, C182S104000
Reexamination Certificate
active
06474663
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a combined pair of ladders and transportation dolly device. More specifically, the device is such that in one mode of operation, the device is able to be used as a pair of ladders and in a further mode, the device permits tansportation of a load.
2. Information Disclosure Statement
In the prior art, it is known to combine a pair of step ladders with a platform such that the step ladders can be converted to a transportation dolly for transporting a load. The present invention provides a distinct improvement over the known arrangements in that a tie bar is provided for urging pivotal movement of the platform so that transportation of a load placed on the platform is facilitated.
Therefore, it is a primary feature of the present invention, to provide a combined pair of ladders and transportation dolly device that overcomes the problems associated with the prior art devices and which make a considerable contribution to the art of transporting packages and the like.
Other features and advantages of the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description contained herein with reference to the annexed drawings showing a preferred embodiment of the present invention.
SUMMARY OF THE INVENTION
The present invention relates to a combined pair of ladders and transportation dolly device. The device includes a first framework which has a first and a second end and a second framework which has a first and a second extremity. The first extremity of the second framework is pivotally secured to the first end of the first framework about a first pivotal axis. A loading platform is provided for supporting a load. The platform has a first and a second edge and the platform is pivotally secured to the second end of the first framework about a second pivotal axis. The second axis is disposed between the first and the second edges of the platform. A tie bar having a first and a second termination is arranged such that the first termination is pivotally secured to the second edge of the platform about a third pivotal axis. The second termination of the tie bar is pivotally secured to the second framework about a fourth pivotal axis. The fourth pivotal axis is disposed between the first and the second extremities of the second framework. A wheel is rotatably secured to the platform and the arrangement is such that in a first mode of operating the device, when the first and second frameworks are pivoted away from each other, the frameworks constitute a pair of ladders. Additionally, in a second mode of operation of the device, when the first and the second frameworks are pivoted towards each other, the wheel permits transportation of the device together with the load supported on the platform.
In a more specific embodiment of the present invention, the first framework includes a first and a second rail, the rails being spaced relative to each other. Also, the rails are disposed parallel relative to each other.
Furthermore, the first framework further includes a step having a first and a second side. The step extends between the first and the second rails.
More specifically, the first side of the step is secured to the first rail and the second side of the step is secured to the second rail. Additionally, the step is disposed between the first and the second ends of the first framework
The second framework includes a first railing and a second railing which is spaced relative to the first railing. Preferably, the railings are disposed parallel to each other and the second framework further includes a rung having a first and a second side. The rung extends between the railings.
The first side of the rung is secured to the first railing and the second side of the rung is secured to the second railing. Also, the rung is disposed between the first and second extremities of the second framework.
Moreover, the platform includes a first portion having a frontward and a rearward end for supporting the load. A second portion has a bottom and a top edge with the bottom edge being secured to the rearward end of the first portion and extending angularly from the rearward end such that the portions cooperate together to support the load.
The platform further includes a side member which is secured to and extends from the second portions towards the second edge of the platform. A second side member is secured to and extends from the second portion towards the second edge of the platform. The first and the second side members are disposed spaced and parallel relative to each other. The second pivotal axis extends through the first and the second side members.
The first, second, third and fourth pivotal axes are disposed parallel and spaced relative to each other.
The device further includes a further tie bar which is disposed spaced and parallel to the tie bar. The further tie bar has a further first termination and a further second termination. The third pivotal axis extends through the first termination and the further first termination. The fourth pivotal axis extends Through the second termination and the further second termination.
The device further includes a further wheel, the wheel and the further wheel being rotatable about the third pivotal axis.
Additionally, when the second framework is pivoted from the first to the second mode thereof, the tie bar urges the platform about the third pivotal axis such that the wheel causes the platform and the load disposed thereon to be raised so that the device operates in the second mode thereof.
Also, the device according to the present invention includes a handle which extends from the first end and the first extremity of the frameworks for stabilizing a user of the device when the device is being used in the first mode and for assisting a user in lifting the load when the device is being operated in the second mode thereof as a transportation dolly.
Many modifications and variations of the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description contained hereinafter. However, such modifications and variations fall within the spirit and scope of the present invention as defined by the appended claims.
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Archer David J.
Walsh Donald P.
Zeender F.
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