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US 2003/0155178 A1Published application
Combined stepladder and hand truck assembly
OwnerHoe Gwan Yooinventor
Life of this patent
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Abstract
A combined stepladder and hand truck assembly is provided. The assembly comprises a first frame having two side rails, a second frame pivotally attached to the back side of the first frame and having two side rails, and a third frame pivotally attached to the front side of the first frame and having two side rails. Steps and bars are provided so that they form a parallel link together with the side rails of the first frame. Two casters attached at the lower end of the first frame. A tool tray is provided at the lower end of the third frame. The tray is kept vertical to the frames when the assembly is used as a hand truck, and is kept horizontal when the assembly is used as a stepladder and the third frame is rotated upward to support the tool tray in a high position.
Claims19
A combined stepladder and hand truck assembly comprising:
- a) a first frame having two side rails, each of the side rails having a lower end;
- b) a second frame pivotally attached to the back side of the first frame, the second frame having two side rails, each of the side rails of the second frame having an upper end and pivotally attached to the side rail of the first frame at the upper end;
- c) a third frame pivotally attached to the front side of the first frame, the third frame having two side rails, each of the side rails of the third frame having an upper end and a lower end and pivotally attached to the side rail of the first frame at the upper end;
- d) two bars;
- e) a plurality of steps, the steps pivotally attached to the side rails of the first frame and the bars so that the steps, the side rails of the first frame, and the bars form a parallel link;
- f) a lock securing the second frame with the first frame at an acute angle between the second frame and the first frame;
- g) two casters attached at the lower end of the side rail of the first frame;
- h) a fastener securing the third frame to the first frame;
- i) a tray rotatably attached to the third frame at the lower ends of the side rails of the third frame;
- and
- j) a stop limiting the rotation of the tray;
- wherein the assembly has a folded position, a hand truck position, a stepladder position, and a tool tray position;
- wherein in the folded position, the second frame and the third frame abut on the first frame, the lock is released, the fastener is released, the link is folded between the side rails of the first frame and the second frame, and the tray is folded between the side rails of the third frame;
- wherein in the hand truck position, the second frame and the third frame abut on the first frame, the lock is released, the fastener is released, the link is folded between the side rails of the first frame and the second frame, the tray is rotated downward until the tray abuts on the stop so that the tray is substantially vertical to the third frame;
- wherein in the stepladder position, the second frame is pivoted so that it makes the acute angle with the first frame, the lock is engaged, the third frame abuts on the first frame, the fastener is released, the link is unfolded so that the steps are substantially horizontal, and the tray is folded between the side rails of the third frame;
- and
- wherein in the tool tray position, the second frame is pivoted so that it makes the acute angle with the first frame, the lock is engaged, the third frame is rotated upward, the fastener is engaged, the link is unfolded so that the steps are substantially horizontal, and the tray is rotated until the tray abuts on the stop so that the tray is substantially horizontal.
14 more elements
A combined stepladder and hand truck assembly comprising:
- a) a first frame having two side rails, each of the side rails having a lower end;
- b) a second frame pivotally attached to the back side of the first frame, the second frame having two side rails, each of the side rails of the second frame having an upper end and pivotally attached to the side rail of the first frame at the upper end;
- c) a third frame pivotally attached to the front side of the first frame, the third frame having two side rails, each of the side rails of the third frame having an upper end and a lower end and pivotally attached to the side rail of the first frame at the upper end;
- d) two bars;
- e) a plurality of steps, the steps pivotally attached to the side rails of the first frame and the bars so that the steps, the side rails of the first frame, and the bars form a parallel link;
- f) a lock securing the second frame with the link at an acute angle between the second frame and the first frame;
- g) two casters attached at the lower end of the side rail of the first frame;
- h) a fastener securing the third frame to the first frame;
- i) a tray rotatably attached to the third frame at the lower ends of the side rails of the third frame;
- and
- j) a stop limiting the rotation of the tray;
- wherein the assembly has a folded position, a hand truck position, a stepladder position, and a tool tray position;
- wherein in the folded position, the second frame and the third frame abut on the first frame, the lock is released, the fastener is released, the link is folded between the side rails of the first frame and the second frame, and the tray is folded between the side rails of the third frame;
- wherein in the hand truck position, the second frame and the third frame abut on the first frame, the lock is released, the fastener is released, the link is folded between the side rails of the first frame and the second frame, the tray is rotated downward until the tray abuts on the stop so that the tray is substantially vertical to the third frame;
- wherein in the stepladder position, the second frame is pivoted so that it makes the acute angle with the first frame, the lock is engaged, the third frame abuts on the first frame, the fastener is released, the link is unfolded so that the steps are substantially horizontal, and the tray is folded between the side rails of the third frame;
- and
- wherein in the tool tray position, the second frame is pivoted so that it makes the acute angle with the first frame, the lock is engaged, the third frame is rotated upward, the fastener is engaged, the link is unfolded so that the steps are substantially horizontal, and the tray is rotated until the tray abuts on the stop so that the tray is substantially horizontal.
14 more elements
Dependencies are inferred from the claim text.