Work Ladder Used as Working Platform

Abstract

A working ladder capable of serving as a working platform, comprises a ladder frame body having a front portion and a top; and a step assembly. The step assembly comprises at least a bottom step and an upper step located above the bottom step; the rear shaft comprises a bottom rear shaft and an upper rear shaft; two movable auxiliary support rods capable of swinging up and down are disposed in the front portion of the ladder frame body; an auxiliary shaft for the rear end of the bottom step to rest on is horizontally disposed on the top of the ladder frame body; when the auxiliary support rods are in a downward position, the rear end of the bottom step rests on the lowermost bottom rear shaft; when the auxiliary support rods are in a upwardly position, the bottom step moves upwardly to the top of the ladder frame body, and meanwhile the rear end of the bottom step rests on the auxiliary shaft. The steps of the working ladder can be used as working platforms.

Claims

1. A working ladder capable of serving as a working platform, comprising: a ladder frame body which can be expanded and folded, having a front portion and a top; and a step assembly which is disposed on the ladder frame body and able to be folded; wherein, the step assembly comprises at least two steps, each step having a front end and a rear end, arranged one above another at intervals, and a rear shaft for the rear end of each step to rest on; a bottommost step is a bottom step, and a step located above the bottom step is an upper step; the rear shaft comprises a bottom rear shaft for the rear end of the bottom step, an upper rear shaft for the rear end of the upper step; two movable auxiliary support rods capable of swinging up and down are disposed in the front portion of the ladder frame body, the front end of the bottom step is rotatably disposed between the two auxiliary support rods, and an auxiliary shaft for the rear end of the bottom step to rest on is horizontally disposed on the top of the ladder frame body; when the auxiliary support rods are in a downward position, the rear end of the bottom step rests on the lowermost bottom rear shaft; when the auxiliary support rods are in a upwardly position, the bottom step moves upwardly to the top of the ladder frame body, and meanwhile the rear end of the bottom step rests on the auxiliary shaft.

2. The working ladder of claim 1, wherein the ladder frame body comprises a pair of front side rails and a pair of rear side rails, the side rails of each pair are separated from each other into two sides, two side rails on a same side are hinged together, and the auxiliary support rods are rotatably arranged on front end surfaces of the front side rails.

3. The working ladder of claim 2, wherein the front end of the upper step is rotatably disposed between the two front side rails; the upper rear shaft is fixed between the two rear side rails; two upper connecting rods are rotatably connected to left and right sides of the upper step adjacent to the bottom step; two lower connecting rods are rotatably connected to lower portions of the two rear side rails; an end of an upper connecting rod and an end of a lower connecting rod on a same side are both rotatably connected to one side of the bottom rear shaft through a rotating shaft.

4. The working ladder of claim 3, wherein each of the two front side rails is fixed with an U-shaped fixed plates; the left and right sides of the front end of the upper step are rotatably disposed on the fixed plates, respectively; the auxiliary support rods are rotatably disposed within U-shaped grooves of the fixed plates.

5. The working ladder of claim 2, wherein the top of the front side rail and the top of the rear side rail on a same side are hinged together through a connecting member which is fixed on the top of the front side rail, and the top of the rear side rail is rotatably connected to the connecting member.

6. The working ladder of claim 1, wherein a first bore forming a first handle for pulling the bottom step is formed on the bottom step, and a second bore forming a second handle for pulling the upper step is formed on the upper step.

7. The working ladder of claim 1, wherein the front end surface of the upper step adjacent to the bottom step is arranged with recessed sections which are bent inwardly.

8. The working ladder of claim 1, wherein a connection structure for detachably connecting the bottom rear shaft or the auxiliary shaft is disposed on the bottom surface of the bottom step.

9. The working ladder of claim 8, wherein the connection structure comprises two holders and a driving structure for driving the holders to slide forward and back; limiting openings running through a width direction of the bottom step and having a shape matched with the bottom rear shaft or the auxiliary shaft are disposed on the bottom surface of the bottom step; the holders are positioned on the bottom surface of the bottom step and are able to slide forward and back; two stoppers extending to the underneath of the limiting openings are disposed in rear portions of the holders; when the bottom rear shaft or the auxiliary shaft is located within the limiting openings, the stoppers are located below the bottom rear shaft or the auxiliary shaft.

10. The working ladder of claim 9, wherein the driving structure comprises a pull rod attached to the holders, and the pull rod is positioned on the bottom surface of the bottom step and able to slide front and back; a handle is connected to a tail end of the pull rod, and the handle is also positioned on the bottom surface of the bottom step and able to slide forward and back; the pull rod is U-shaped, and one of the holders is fixed on each of two straight rod portions of the pull rod; the handle is connected to a middle portion of a horizontal rod portion of the pull rod.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a perspective view of a working ladder capable of serving as a working platform according to an embodiment of the present invention (when the working ladder is used);

[0021] FIG. 2 is a perspective view of the working ladder of FIG. 1 when one portion of the working ladder is cut off;

[0022] FIG. 3 is a perspective view of a bottom step with the connection structure according to the embodiment of the present invention;

[0023] FIG. 4 is an exploded view of the bottom step with the connection structure according to the embodiment of the present invention;

[0024] FIG. 5 is another perspective view of the working ladder according to the embodiment of the present invention (when the working platform is in another status);

[0025] FIG. 6 is a perspective view of the working ladder of FIG. 5 when one portion of the working ladder is cut off; and

[0026] FIG. 7 is a perspective view of the working ladder according to the embodiment of the present invention (when the working ladder is folded).

DETAILED DESCRIPTION OF THE INVENTION

[0027] To enable a further understanding of the present invention content of the invention herein, refer to the detailed description of the invention and the accompanying drawings below:

[0028] FIG. 1-FIG. 7 show a preferred embodiment of the present invention.

[0029] A working ladder capable of serving as a working platform, comprises: a ladder frame body which can be expanded and folded, having a front portion and a top; and a step assembly which is disposed on the ladder frame body and able to be folded.

[0030] The ladder frame body comprises a pair of front side rails 7 and a pair of rear side rails 8, the side rails of each pair are separated from each other into two sides; the top of the front side rail 7 and the top of the rear side rail 8 on a same side are hinged together through a connecting member 9 which is fixed on the top of the front side rail 7, and the top of the rear side rail 8 is rotatably connected to the connecting member 9; support rods are disposed between the two front side rails 7 and also disposed between the two rear side rails 8.

[0031] The step assembly comprises at least two steps, each step having a front end and a rear end, arranged one above another at intervals, and a rear shaft for the rear end of each step to rest on; a bottommost step is a bottom step 1, and the step located above the bottom step 1 is an upper step 2, there is only one upper step 2 in this embodiment; the rear shaft comprises a bottom rear shaft 3 for the rear end of the bottom step 1 and an upper rear shaft 4 for the rear end of the upper step 2.

[0032] Two movable auxiliary support rods 5 capable of swinging up and down are disposed in the front portion of the ladder frame body; the movable auxiliary support rods 5 are rotatably disposed on front end surfaces of the front side rails 7; each of the two front side rails 7 is fixed with an U-shaped fixed plates 10; U-shaped grooves of the fixed plates 10 are arranged forward, and the auxiliary support rods 5 are rotatably disposed within the U-shaped grooves of the fixed plates 10.

[0033] The front end of the bottom step 1 is rotatably disposed between the two auxiliary support rods 5 through a rotating shaft 17; an auxiliary shaft 6 for the rear end of the bottom step 1 to rest on is horizontally disposed on the top of the ladder frame body; the auxiliary shaft 6 can be disposed between the two connecting members 9, or can be disposed on connecting arms on two sides of a tool box, as long as the auxiliary shaft is horizontally disposed in the upper portion of the ladder frame body; a first bore 16 forming a first handle for pulling the bottom step 1 is formed on the bottom step 1; the front end surface of the upper step 2 adjacent to the bottom step is arranged with recessed sections 22 which are bent inwardly, the recessed sections 22 are matched with the shape of two legs of a person in shape.

[0034] The front end of the upper step 2 is rotatably disposed between the two front side rails 7; the left and right sides of the front end of the upper step 2 are rotatably disposed on the fixed plates 10, respectively; the upper rear shaft 4 is fixed between the two rear side rails 8; two upper connecting rods 11 are rotatably connected to the left and right sides of the upper step 2 adjacent to the bottom step 1; two lower connecting rods 12 are rotatably connected to lower portions of the two rear side rails 8; an end of an upper connecting rod 11 and an end of a lower connecting rod 12 on a same side are both rotatably connected to one side of the bottom rear shaft 3 through a rotating shaft; a second bore 21 forming a second handle for pulling the upper step 2 is formed on the upper step 2.

[0035] When the auxiliary support rods 5 are in a downward position, the rear end of the bottom step 1 rests on the lowermost bottom rear shaft 3; when the auxiliary support rods 5 are in a upwardly position, the bottom step 1 moves upwardly to the top of the ladder frame body, and meanwhile the rear end of the bottom step 1 rests on the auxiliary shaft 6.

[0036] A connection structure for detachably connecting the bottom rear shaft 3 or the auxiliary shaft 6 is disposed on the bottom surface of the bottom step 1.

[0037] As shown in FIGS. 3 and 4, the connection structure comprises two holders 13 and a driving structure for driving the holders 13 to slide front and back; limiting openings 12 running through a width direction of the bottom step and having a shape matched with the bottom rear shaft 3 or the auxiliary shaft 6 are disposed on the bottom surface of the bottom step 1; the holders 13 are positioned on the bottom surface of the bottom step 1 and are able to slide front and back; two stoppers 131 extending to the underneath of the limiting openings 12 are disposed in rear portions of the holders 13; when the bottom rear shaft 3 or the auxiliary shaft 6 is located within the limiting openings 12, the stoppers 131 are located below the bottom rear shaft 3 or the auxiliary shaft 6.

[0038] The driving structure comprises a pull rod 14 attached to the holders 13, and the pull rod 14 is positioned on the bottom surface of the bottom step 1 and able to slide front and back; a handle 15 is connected to a tail end of the pull rod 14, and the handle 15 is also positioned on the bottom surface of the bottom step 1 and able to slide front and back; the pull rod 14 is U-shaped, and one of the holders 13 is fixed on each of two straight rod portions of the pull rod 14; the handle 15 is connected to a middle portion of a horizontal rod portion of the pull rod 14.

[0039] The working principle and process of the working ladder are as follows.

[0040] As shown in FIGS. 1 and 2, when the working ladder serves as a ladder, the ladder frame body is expanded, the rear end of the upper step 2 rests on the upper rear shaft 4. Meanwhile, when the movable auxiliary support rods 5 are turned down, the rear end of the bottom step 1 rests on the lowermost bottom rear shaft 3, the bottom rear shaft 3 is inserted into the limiting openings 12 of the bottom step 1, and the stoppers 131 of the holders 13 are located below the bottom rear shaft 3. In this case, the bottom step 1 serves as a step.

[0041] As shown in FIGS. 5 and 6, when the working ladder serves as a working platform, the handle 15 is pulled forward by a hand; the handle 15 drives the holders 13 to move forward; and the stoppers 131 of the holders 13 move forward to leave the underneath of the bottom rear shaft 3, that is, the stoppers 13 does not restrict the bottom rear shaft 3 anymore. Meanwhile, a hand is put into the first bore 16 of the bottom step 1 to pull the bottom step 1 upward, so that the bottom step 1 is separated from the bottom rear shaft 3, then extended out from the front of the ladder frame body and turned up. Turning the bottom step 1 up drives the movable auxiliary support rods 5 to turn up, until the bottom step 1 is turned over the ladder frame body. Then, the rear end of the bottom step 1 rests on the auxiliary shaft 6, and the auxiliary shaft 6 is inserted into the limiting openings 12 of the bottom step 1. The handle 15 is pushed backward, the handle 15 drives the holders 13 to move backward, and the stoppers 131 of the holders 13 moves backward to the underneath of the auxiliary shaft 6, so that the rear end of the bottom step 1 is positioned on the auxiliary shaft 6. The front end of the bottom step 1 is supported by the movable auxiliary support rods 5, while the rear end thereof is supported by the auxiliary shaft 6. Thus, the bottom step 1 may serve as a working platform which allows a user to perform operations such as sawing, cutting or carving on this platform.

[0042] As shown in FIG. 7, during folding, a hand is put into the second bore 21 on the upper step 2 to pull the upper step 2 upward. The rear end of the upper step 2 is separated from the bottom rear shaft 3 and the upper step 2 moves upward, and meanwhile the front side rails 7 and the rear side rails 8 are folded. The upper step 2 drives the bottom step 1 to move upward through the upper connecting rods 11 and the lower connecting rods 12 until the working ladder is folded. The folding way is similar to that of the existing working ladders.

[0043] The protection scope of the present invention is not limited to each embodiments described in this description. Any changes and replacements made on the basis of the scope of the present invention patent and of the description shall be included in the scope of the present invention patent.