JPH0311360Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement of a stepladder with casters.

Conventional stepladders used in libraries, etc. have casters at the bottom ends of all four legs, the front and rear frames of the tread are covered with stainless steel, and each leg is made of round or square pipes. Since they were made by bending and the tops of the legs were at the same height as the top tread, I often felt uneasy under my feet.

In addition, with this type of four-legged stepladder that has casters on each leg, the load is not applied evenly depending on the position of the tread, and if you step on the end of the tread, the stepladder will immediately wobble, which is extremely dangerous. It was hot.

It has already been proposed to provide casters at the lower ends of two of the four legs of a desk, but this was only for the purpose of making the desk easier to move, and was not a consideration for safety.

Furthermore, this type of stepladder with casters has a large number of parts, complicates the manufacturing process, and is expensive.

This invention eliminates these defects in conventional stepladders with casters, and the gist is that a hard rubber leg seat is fitted instead of casters at the lower end of each of the two front legs, and the two front legs are fitted with hard rubber leg seats instead of casters. A caster is provided only at the lower end of each hind leg, the upper and lower ends of the hind leg are connected by reinforcing pipes that intersect with each other, and the surface of each tread and the front and rear side frames are made of plastic or rubber sheets with anti-slip stripes. The front and rear ends of the sheet are wrapped around the U-shaped portions of the front and rear ends of the tread, and fixed pieces are fitted into the U-shaped portions, and the upper ends of the square pipes of the front and rear legs and the uppermost horizontal corner are fixed. This stepladder with casters is characterized in that the corner end of the pipe is connected with an elbow-shaped plastic or aluminum die-cast connecting member, and the horizontal square pipe is made higher than the height of the step board.

An embodiment of the stepladder with casters according to the invention will be described with reference to the drawings.

A hard rubber leg seat 2, 2 is fitted and fixed to each lower end of two front legs 1, 1 made of square pipe, and to each lower end of two rear legs 3, 3 made of square pipe similar to the front legs, Casters 4, 4 are provided.

The upper ends of the front legs 1, 1 and the rear legs 3, 3 and both ends of the uppermost horizontal square pipes 7, 7 are connected with elbow-shaped plastic or aluminum die-cast connecting parts 8, 8, and the front legs 1, 1 and The parts where the rear legs 3, 3 and the tread plates 11, 13 (described later) are installed are connected and integrated by the intermediate lower horizontal square pipe 5 and the intermediate upper horizontal square pipe 6, and the upper and lower parts are connected to each other by the inner surfaces of both sides of the rear legs 3, 3. Near the ends are connected and reinforced vertically with reinforcing pipes 9, 9 that intersect with each other, and the intersections are connected with bolts, nuts, etc. 10.

The front and rear ends of the lower tread plate 11 and the upper tread plate 13 are pre-shaped downwardly and inwardly into U-shapes 11a, 11b, 13a,
A plastic or rubber sheet 15 bent at 13b and forming an anti-slip stripe perpendicular to the stepping direction is covered on the surfaces of these treads and the front and rear side frames, and the front and rear ends of the sheet are attached to the U-shaped portions 11a, 11.
b, 13a, 13b, partially wrapped and fitted,
A fixing piece 16 is fitted into each U-shaped portion 11a, 11b, 13a, 13b to integrally fix the sheet to each step board.

The lower intermediate lower tread plate 11 is fixed to a bolt threading hole (not shown) horizontally drilled in the front half of the side surface of the intermediate lower horizontal square pipe 5 via the L-shaped fixing piece 5', and the intermediate upper horizontal square pipe 5 is fixed. The upper intermediate lower step plate 1 is inserted through the shape fixing piece 6' into a bolt screw hole (not shown) drilled horizontally in the rear half of the side surface of the pipe 6.
Fix 3 to make one piece.

The stepladder with casters having the above-mentioned configuration has a hard rubber leg seat fixed to the lower end of the front legs 1, 1 instead of casters, so that it does not slip carelessly, increases the sense of stability, and is stable regardless of the position where the stepboard is stepped. The casters 4, 4 provided at the lower ends of the rear legs 3, 3
Therefore, when moving, it can be easily moved to a desired position by grasping the front legs 1, 1 and lifting them slightly.

The upper and lower footboards 13 and 11 are made of plastic or rubber sheets 15 with anti-slip stripes formed thereon.
The front and rear ends of the sheet are covered with U-shaped parts 11a,
11b, 13a, 13b, and the fixing piece 16 was fitted to fix it to each footboard, so both ends of the sheet were wrapped around these U-shaped parts 11a, 11b, 13.
a, 13b, and the sheet will not shift or move during use, even without providing any other members.

Therefore, compared to the conventional stepladder surrounded by a stainless steel frame, it is easier to manufacture, and the uppermost corner is the same as the top of each of the front and rear legs 1 and 3 of the square pipe. It can be easily assembled by simply fitting the elbow-shaped connecting members 8 to both ends of the pipe 7 and connecting them.
Because it is made higher than the previous stepladder, there is no sense of danger underfoot, and it is extremely stable compared to conventional stepladders.

Furthermore, since the front and rear legs 1 and 3 are long, there is almost no waste in removing material from the long rectangular pipe.

[Brief explanation of drawings]

Figure 1 is a front view of the stepladder with casters according to this invention, Figure 2 is its back view, Figure 3 is a left side view of Figure 1 with the lower end of the front leg partially cut away, and Figure 4 is a left side view of Figure 1 with the lower end of the front leg partially cut away.
The figure is a plan view of Fig. 1, and Fig. 5 is a plan view of Fig. 4.
FIG. 6 is a perspective view of FIG. 1, which is a partially enlarged cross-sectional view. 1... Front leg, 2... Hard rubber leg seat, 3... Rear leg, 4... Caster, 5... Middle lower horizontal square pipe, 6... Middle upper horizontal square pipe, 7... Top horizontal angle Pipe, 8... Elbow type connection member, 9...
Cross-reinforced pipe, 10... Bolt, nut, 11
...Lower stepboard, 11a, 11b...Lower stepboard 11
U-shaped portion at the front and rear ends of 13... Upper tread plate, 13
a, 11b... U-shaped portion at the front and rear ends of the upper step board 13, 15... Plastic or rubber sheet with anti-slip stripes formed thereon, 16... Fixing piece.

Claims (1)

[Scope of Claim for Utility Model Registration] Front legs 1, 1 made of square pipes with hard rubber leg seats 2 fitted at each lower end; Casters 4, 4 also made of square pipes, and casters 4, 4 at each lower end.
rear legs 3, 3 provided with; elbow-shaped connecting portions 8, 8 connecting the upper ends of the front legs 1, 1 and the rear legs 3, 3 and both ends of the uppermost horizontal square pipes 7, 7; An intermediate lower horizontal square pipe 5 and an intermediate upper horizontal square pipe 6 which connect the front legs 1, 1 and the rear legs 3, 3 where the footboards are provided; 1
reinforcing pipes 9, 9 connected at 0 and having each end fixed near the upper and lower ends on each inner surface of the rear legs 3, 3; U-shaped portions 11a, 11b formed by bending the front and rear ends downward and inward; , and a tread plate 11 fixed to the front half of the lower horizontal square pipe 5 of the intermediate portion, and a U-shaped portion 13a formed by bending the front and rear ends downward and inward.
13b and fixed to the rear half of the intermediate upper horizontal square pipe 6; a tread plate 13 having a stripe perpendicular to the stepping direction and covering the surface of each tread plate 11, 13 and the front and rear frames; , the U-shaped portions 11a, 11b, 13 of each tread at the front and rear ends.
A stepladder with casters, comprising: a plastic or rubber sheet 15 rolled up and fixed in the interiors of a and 13b;