JP2000352285A - Stepladder with horizontally adjusting function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stepladder capable of relatively reducing a level difference and capable of maintaining a parallel state by easily grounding legs on the ground surface in an almost flat place. SOLUTION: This stepladder 1 with a horizontally adjusting function is a stepladder 1 having four legs 2A to 2D and becoming an almost rectangular shape in a diagram drawn by connecting the respective tips of the four legs 2A to 2D, and has a leg length adjusting means 3 for continuously extending/ contracting the respective leg lengths of either one set of legs 2A, 2C positioned on a diagonal line of a rectangle. A freely rotatable leg stand is suitably provided on the respective tips of the four legs 2A to 2D. The length adjusting means 3 is provided, and a level is suitably provided on a connecting arm 7 for joining respective ones of a set of legs 2A, 2C positioned on the diagonal line of the reactangle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stepladder with a horizontal adjustment function, and more particularly to a stepladder with a horizontal adjustment function suitable for construction work and work at a high place in a home.

[0002]

2. Description of the Related Art A stepladder conventionally used comprises, for example, four legs 21A to 21D, a step 22 for lifting and lowering, a hinge portion 23, a latch 24, and the like, as shown in FIG. In most cases, the leg lengths 21A to 21D are fixed.

When the stepladder 20 is used on a scaffold or the like having a step, the step is adjusted by using a plate or the like, but in reality, the stepladder is used in a state where the stepladder shakes or tilts. In many cases, safety was lacking.

In order to solve this problem, for example, Japanese Utility Model Laid-Open No. 63-159100 discloses a ladder having a function of adjusting the height of a leg in order to maintain a parallel state on a sloped slope. It has been disclosed.

[0005] In addition, in a four-legged stepladder, for the purpose of maintaining a parallel state, for example, Japanese Laid-Open Utility Model Publication No. 6-47493 and Japanese Laid-Open Utility Model Publication No. 8-1020 adjust the leg length of each leg. There is disclosed a technique for maintaining a parallel state on an inclined slope or a step.

[0006]

However, in the four-legged stepladder, it is necessary to adjust the leg length of each leg in order to maintain a parallel state even in a place where the level difference is relatively small and almost flat. Therefore, there are four parts to be adjusted, and there is a problem that the operation is complicated.

Therefore, the present invention has been made in view of the above-mentioned problems in the conventional stepladder and the like, and in a place where the level difference is relatively small and almost flat, the legs are easily grounded to the ground and parallelized. An object of the present invention is to provide a stepladder capable of maintaining a state.

[0008]

In order to achieve the above object, an invention according to claim 1 is a stepladder having a horizontal adjustment function, the stepladder having four legs, and the tip of each of the four legs. Are connected to each other to form a substantially rectangular shape, and a leg length adjusting means for continuously expanding and contracting each leg length of one of the pairs of legs located on a diagonal of the rectangle.

According to the first aspect of the present invention, another pair of legs having leg length adjusting means, with two legs located on the diagonal of a rectangle having no function of expanding and contracting as fulcrums, is provided. By continuously expanding and contracting, all four legs can be brought into contact with the ground.

[0010] The invention according to claim 2 is characterized in that each of the four legs has a rotatable footrest at a tip thereof. Thus, since the four legs have a rotatable footrest at each tip, the footrest can be rotated according to the shape of the ground or the like, and the parallel state can be more stably maintained. .

The invention according to claim 3 is characterized in that the leg length adjusting means is provided, and a level is provided on a connecting arm for connecting each of a pair of legs located on a diagonal of the rectangle. This allows the leg length adjustment work to be performed while checking the levelness.

According to a fourth aspect of the present invention, the connecting arm includes a first arm portion and a second arm portion for holding the first arm portion so that the first arm portion can be inserted therein. It is characterized by being fixed to a first arm and being insertable into the second arm together with the first arm. Thus, the level can be protected when the stepladder is stored.

[0013]

Next, a specific example of an embodiment of a stepladder with a horizontal adjustment function according to the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of a stepladder (hereinafter abbreviated as "stepladder") having a horizontal adjustment function according to the present invention.
The stepladder 1 is provided with four legs 2A to 2D, and is configured such that a figure drawn by connecting the tips of the four legs 2A to 2D becomes a rectangle, and the legs 2A, 2B, or 2 Between 2C and 2D, a step for elevating (hereinafter, referred to as “step”)
Step 7) is provided.

At the upper end of the stepladder 1, a ladder part 10A composed of the legs 2A, 2B and the step 7 and a ladder part 10B composed of the legs 2C, 2D and the step 7 are openably and closably connected. Hinge part 8 and ladder part 10A when using stepladder 1
A latch 9 for fixing the distance between the ladder portion 10B and the ladder portion 10B is provided.

Of the four legs 2A to 2D, one pair of legs 2A and 2C located on the diagonal of the rectangle includes:
Leg length adjusting means 3 for continuously expanding and contracting the leg lengths of these legs 2A and 2C is provided.

As shown in FIG. 2, the leg length adjusting means 3 includes a rotary shaft 4 having a male screw portion 4a screwed with a female screw portion 2a formed at the end of the leg 2A (2C) and a spherical end portion 4b. When,
It comprises a handle 5 for rotating the rotary shaft 4 in the direction of the arrow in the figure, and a footrest 6 rotatably supported by the spherical end 4b of the rotary shaft 4 around the spherical end 4b. You.

As shown in FIG. 1, the legs 2A and 2C
Is provided with a telescopic connecting arm 11, which is provided with two arm portions 11A, 1A and 1A.
1B.

The arm 11A is configured to be insertable into the arm 11B, and is extendable in the direction of arrow C in FIG. The end of the arm 11B is connected to the leg 2A and the leg 2A.
B (FIG. 1) is fixed so as to be rotatable around the rotary shaft bolt 12 at the step 7B bridged between them. A level 13 is provided on the upper surface of the arm 11A,
At the end, a fixing bolt 1 erected at a step 7A which is hung between the leg 2C and the leg 2D (FIG. 1) during use.
4 is formed with a locking recess 11a. Also, as shown in FIG. 3B, the legs 2A and 2B (FIG. 1)
The fixing bolt 15 that engages with the locking concave portion 11a of the arm portion 11A when the stepladder 1 is stored is erected at the step 7B bridged between the steps.

Next, a method of using the stepladder 1 having the above configuration will be described.

When the stepladder 1 is stored, that is, before use, the arm portion 11A is inserted into the arm portion 11B, as shown in FIG.
1a and the fixing bolt 15 are engaged. Here, since the level 13 is housed inside the arm 11B together with the arm 11A, the level 13 can be protected.

When using the stepladder 1, the arm 11A
The engagement between the locking recess 11a and the fixing bolt 15 is released,
The connecting arm 11 is extended by pulling out the arm 11A from the arm 11B, and the locking recess 11a of the arm 11A is engaged with the fixing bolt 14, as shown in FIG. At the same time, the gap between the ladder portion 10A and the ladder portion 10B is fixed using the latch 9 in FIG.

Next, at the place of use, the leg length adjusting means 3
The positions of the legs 2B and 2D having no legs are fixed, and then the handle 5 of the leg length adjusting means 3 provided on the legs 2A and 2C shown in FIG. By operating, four legs 2A of stepladder 1
2D is securely grounded to the ground, and the installation of the stepladder 1 is completed. At this time, since the level 13 is attached at the same level as that of the lowermost step 7, the leg length adjusting means 3 can be adjusted while looking at the level 13 at a lower position, so that workability is good.

In the above embodiment, the leg length adjusting means 3 having the rotary shaft 4 is used. However, the present invention is not limited to such a screw type, and a manual type or hydraulic type jack may be used. It is.

[0025]

As described above, according to the first aspect of the present invention, two pairs of two legs which are located on diagonal corners of a rectangle having no function of expanding and contracting are used as fulcrums. By continuously expanding and contracting the legs, all four legs can be grounded to the ground, so the level difference is relatively small,
It is possible to provide a stepladder that can easily keep the legs in contact with the ground and maintain a parallel state in a nearly flat place.

According to the second aspect of the present invention, since each of the four legs has a rotatable leg at the tip thereof, the leg is rotated according to the shape of the ground or the like, and is more stable. Thus, a stepladder that can maintain a parallel state can be provided.

According to the third aspect of the present invention, since the operation of adjusting the leg length can be performed while checking the levelness, it is possible to provide a stepladder that can more easily perform the operation of setting the stepladder. .

According to the fourth aspect of the invention, since the level can be protected when the stepladder is stored, a stepladder which is easier to handle can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a stepladder with a horizontal adjustment function according to the present invention.

FIG. 2 is a detailed view of a portion A in FIG.

FIGS. 3A and 3B are detailed views of a portion B in FIG. 1, wherein FIG. 3A is a perspective view showing a use state, and FIG.

FIG. 4 is a perspective view showing an example of a conventional stepladder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stepladder 2A-2D Leg 3 Leg length adjusting means 4 Rotating shaft 4a Male screw part 4b Spherical end part 5 Handle 6 Footrest 7 Step 8 Hinge part 9 Hatch 10A, 10B Ladder part 11 Connecting arm 11A, 11B Arm part 11a Locking concave part 12 Rotary shaft bolt 13 Level 14 Fixing bolt 15 Fixing bolt

Claims (4)

[Claims] 1. A stepladder having four legs, wherein a figure drawn by connecting the tips of each of the four legs is substantially a rectangle, and each of the steps is located on a diagonal of the rectangle. A stepladder with a horizontal adjustment function, comprising: leg length adjusting means for continuously expanding and contracting each leg length of one of the pairs of legs. 2. A stepladder with a horizontal adjustment function according to claim 1, further comprising a rotatable footrest at each of the four legs. 3. A level according to claim 1, wherein said leg length adjusting means is provided, and a level is provided on a connecting arm for connecting each of a pair of legs located on a diagonal of said rectangle. Stepladder with horizontal adjustment function. 4. The connecting arm includes a first arm portion and a second arm portion that insertably holds the first arm portion, and is configured to expand and contract itself, and the level is fixed to the first arm portion. 4. A stepladder with a horizontal adjustment function according to claim 3, wherein the stepladder can be inserted into the second arm together with the first arm.