Step stool for working at heights

Abstract

The objective is to have the worker stand on the center of the work surface F while performing their task. [Solution] A step stool 10 having a top part 20 with a work surface F and a base part 50 that contacts the floor surface, wherein the height of the work surface F is adjustable, and the work surface F is provided with an indicator to show the worker to stand on the center of the work surface F.

Description

Technical Field

[0001] The present invention relates to a stepladder.

Background Art

[0002] Conventionally, stepladders for working at heights have been known. Patent Document 1 discloses a stepladder whose height of the top plate portion can be changed stepwise by folding or assembling.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a stepladder, particularly when using it with the height of the top plate portion increased, if an operator stands on the peripheral portion of the working surface of the top plate portion to work, the stepladder will not be stable and the work efficiency cannot be achieved. The present invention has been made in view of the above problems, and an object thereof is to enable an operator to work while standing on the central portion of the working surface.

Means for Solving the Problems

[0005] The present invention is a stepladder having a top portion with a working surface and a base portion grounded on the floor surface, wherein the height of the working surface is changeable, and an index indicating to an operator to stand on the central portion of the working surface is provided on the working surface.

Effects of the Invention

[0006] According to the present invention, an operator can be made to work while standing on the central portion of the working surface.

Brief Description of the Drawings

[0007] [Figure 1] This is a perspective view showing an example of a step stool being at a low height. [Figure 2] This is a perspective view showing an example of a step stool being at a high height. [Figure 3] This is a plan view showing an example of the configuration of a step stool. [Figure 4] This is a right-side view showing an example of the configuration of a step stool. [Figure 5] This is a front view showing an example of the configuration of a step stool. [Figure 6] This is a bottom view showing an example of the configuration of a step stool. [Figure 7] This is a right-side view showing an example of a step stool with its height adjusted. [Figure 8] This figure shows an example of indicators applied to a work surface. [Figure 9] This figure shows an example of indicators applied to a work surface. [Figure 10] This figure shows an example of indicators applied to a work surface. [Figure 11] This figure shows an example of indicators applied to a work surface. [Figure 12] This figure shows an example of indicators applied to a work surface. [Modes for carrying out the invention]

[0008] The step stool 10 according to this embodiment will be described below with reference to the drawings. The step stool 10 according to this embodiment allows the height of the top part 20 to be changed in at least two stages. (First Embodiment) Figure 1 is a perspective view showing an example of the step stool 10 with a low height of the top 20. Figure 2 is a perspective view showing an example of the step stool 10 with a high height of the top 20. Figure 3 is a plan view showing an example of the step stool's configuration. Figure 4 is a right side view showing an example of the step stool's configuration. Figure 5 is a front view showing an example of the step stool's configuration. Figure 6 is a bottom view showing an example of the step stool's configuration. For the sake of ease of explanation, the front side is indicated as Fr, the rear side as Rr, the right side as R, and the left side as L, as necessary in each figure. Also, in Figures 1 and 2, the projection 32, which will be described later, is omitted from the illustration.

[0009] The step stool 10 of this embodiment includes a top part 20, a base part 50, and a height adjustment part 60. First, let me explain the celestial section 20. The top section 20 is the part on which workers stand when performing work at height. The top section 20 has a top plate 21 and side walls 34a, 34b, 35a, and 35b. The top section 20 is enclosed by the top plate 21 and the four side walls 34a, 34b, 35a, and 35b, and has an open space at the bottom. The top section 20 is made of synthetic resin and is integrally molded by injection molding, and the entire structure is colored as a first color, for example, blue, by mixing in a coloring agent.

[0010] The tabletop 21 is approximately square in plan view, with sides of 400mm to 600mm (preferably approximately 500mm), and its top surface functions as a work surface F. The tabletop 21 may also be rectangular with sides of 400mm to 600mm. The work surface F is provided with a shoe sole shape 70, which will be described later as an indicator. The top plate 21 has connecting members 22a and 22b at its left and right ends. The connecting members 22a and 22b are for connecting the step stool 10 to other step stools 10 located adjacent to it on the left and right. The connecting members 22a and 22b are bar-shaped and bent into a U-shape. The connecting members 22a and 22b rotate around an axis along the front-to-back direction from their state of being housed on the top plate 21, so that they are positioned beyond the outer edge of the top plate 21, as shown by the dashed line in Figure 3. When the connecting members 22a and 22b are housed on the top plate 21, they are positioned lower than the work surface F so as not to interfere with work.

[0011] The top plate 21 has connected parts 23a and 23b at its front and rear ends. The connected parts 23a and 23b are parts for connecting the step 10 to the connecting members 22a and 22b of other steps 10 adjacent to it in the front and rear directions. The connected parts 23a and 23b are formed in a concave shape downward from the working surface F. The connected parts 23a and 23b are connected at a position lower than the working surface F so as not to interfere with the work when the connecting members 22a and 22b are connected.

[0012] Also, the first positioning parts 24a and 24b are provided at the left and right ends of the top plate 21. The first positioning parts 24a and 24b are located in the region surrounded by the connecting members 22a and 22b. Also, the second positioning parts 25a and 25b are provided at the front and rear ends of the top plate 21. The second positioning parts 25a and 25b are located in the region surrounded by the connected parts 23a and 23b. The first positioning parts 24a and 24b and the second positioning parts 25a and 25b are each formed in a concave shape downward from the working surface F. Here, the depth dimension from the working surface F in the first positioning parts 24a and 24b is substantially the same as the depth dimension from the working surface F in the accommodation space in which the connecting members 22a and 22b are accommodated. Also, the depth dimension from the working surface F in the second positioning parts 25a and 25b is substantially the same as the depth dimension from the working surface F of the connected parts 23a and 23b.

[0013] Here, when two first positioning portions 24a and 24b connect the treads 10 in the front and rear directions, the leg portions 55 of the base portion 50 when stacking other treads 10 straddle over the two connected treads 10. Also, when two second positioning portions 25a and 25b connect the treads 10 in the left and right directions, the leg portions 55 of the base portion 50 when stacking other treads 10 straddle over the two connected treads 10. Therefore, the first positioning portions 24a and 24b and the second positioning portions 25a and 25b are each shaped such that the leg portions 55 of the tread 10 can be fitted from above. The stacked treads 10 are positioned by the first positioning portions 24a and 24b or the second positioning portions 25a and 25b. Therefore, it is also possible for an operator to perform work while standing on the stacked treads 10 with respect to the two connected treads 10.

[0014] Also, insertion portions 26a and 26b are provided at the left and right end portions of the top plate 21. The insertion portions 26a and 26b are located in the regions of the first positioning portions 24a and 24b, respectively, of the top plate 21. Also, two insertion portions 26a and two insertion portions 26b are each formed at a distance in the front - rear direction. Further, the insertion portions 26a and 26b are formed in a concave shape below the first positioning portions 24a and 24b. Note that the right side of the insertion portion 26a is open, and the left side of the insertion portion 26b is open. Also, insertion portions 27a and 27b are provided at the front and rear end portions of the top plate 21. The insertion portions 27a and 27b are located in the regions of the second positioning portions 25a and 25b, respectively, of the top plate 21. Also, two insertion portions 27a and two insertion portions 27b are each formed at a distance in the left - right direction. Further, the insertion portions 27a and 27b are formed in a concave shape below the second positioning portions 25a and 25b. Note that the insertion portions 27a and 27b are in the form of non - open holes and have drain holes on the bottom surface.

[0015] Here, the front insertion parts 26a and 26b are used to insert the leg bases 56 of the legs 55 when other step stools 10 are stacked, so as to straddle the two connected step stools 10 when they are connected at the front. The rear insertion parts 26a and 26b are used to insert the leg bases 56 of the legs 55 when other step stools 10 are stacked, so as to straddle the two connected step stools 10 when they are connected at the rear. On the other hand, the right-side insertion section 27a and the right-side insertion section 27b are used to insert the leg base 56 of the leg portion 55 when other step stools 10 are stacked, so as to straddle the two connected step stools 10 when other step stools 10 are connected on the right side. Also, the left-side insertion section 27a and the left-side insertion section 27b are used to insert the leg base 56 of the leg portion 55 when other step stools 10 are stacked, so as to straddle the two connected step stools 10 when other step stools 10 are connected on the left side.

[0016] Furthermore, the top plate 21 has third positioning portions 28 at each of the four corners, which are near the vertices of the square in a plan view. In a plan view, the shape of the surface of the third positioning portion 28 (including the insertion portion 29 described later) is a composite shape of a fan-shaped shape that spreads out from the vertices of the square and a hook-shaped shape that extends in the front-to-back and left-to-right directions. Each of the third positioning sections 28 is formed in a concave shape downward from the work surface F. The depth dimension of the third positioning section 28 from the work surface F is approximately the same as the depth dimension of the first positioning sections 24a, 24b and the second positioning sections 25a, 25b from the work surface F. Here, the third positioning section 28 is designed to accommodate the legs 55 of the base 50 when stacking one step stool 10 on top of another (see the dashed line in Figure 2). Therefore, each third positioning section 28 is shaped to accommodate the legs 55 of the step stool 10 from above. The stacked step stools 10 are positioned by the four third positioning sections 28. As a result, it is possible for a worker to stand on a stack of step stools 10 that are stacked on top of a single step stool 10 and perform their work.

[0017] Furthermore, the top plate 21 has insertion portions 29 at each of its four corners. Each insertion portion 29 is located within the region of the third positioning portion 28 on the top plate 21. The insertion portions 29 are also formed in a concave shape below the third positioning portion 28. Each insertion portion 29 is perforated and has a drainage hole at its bottom.

[0018] Furthermore, the edges of the top plate 21 have multiple connecting holes 30a, 30b, 31a, and 31b. Two connecting holes 30a are formed in close proximity to the right end of the top plate 21, spaced apart in the front-to-back direction. Similarly, two connecting holes 30b are formed in close proximity to the left end of the top plate 21, spaced apart in the front-to-back direction. Connecting pins for a bridge are inserted into the connecting holes 30a when a plate-shaped bridge is constructed between the step stool 10 and another step stool 10 located to the right of it. Likewise, connecting pins for a bridge are inserted into the connecting holes 30b when a plate-shaped bridge is constructed between the step stool 10 and another step stool 10 located to the left of it.

[0019] Two connecting holes 31a are formed in close proximity to the front end of the top plate 21, spaced apart in the left-right direction. Similarly, two connecting holes 31b are formed in close proximity to the rear end of the top plate 21, spaced apart in the left-right direction. Connecting pins of a bridge are connected to the connecting holes 31a when a plate-shaped bridge is placed between the step stool 10 and another step stool 10 located at a distance to the front of the step stool 10. Likewise, connecting pins of a bridge are connected to the connecting holes 31b when a plate-shaped bridge is placed between the step stool 10 and another step stool 10 located at a distance to the rear of the step stool 10.

[0020] Furthermore, multiple protrusions 32 are formed at intervals across the entire work surface F of the top plate 21 (see Figure 3). The protrusions 32 are approximately circular in plan view, and for example, have a diameter of 10 mm to 20 mm. The protrusions 32 are formed to project upward from the work surface F, and for example, the height dimension from the work surface F to the surface of the protrusion 32 is 1 mm to 2 mm.

[0021] Side wall 34a is formed by hanging downward from the right edge of the top plate 21, and side wall 34b is formed by hanging downward from the left edge of the top plate 21. Side walls 34a and 34b have the same structure, and only side wall 34a will be described here. The side wall 34a has a height of 100 mm to 300 mm (preferably approximately 150 mm), and its side is the exterior surface.

[0022] As shown in Figure 4, the side wall 34a has a pivot shaft 36 which serves as a pivot part for supporting the rotation of the support panel 61a of the height adjustment section 60. Here, the two pivot shafts 36 are fixed inside or within the side wall 34a at positions separated in the front-rear direction such that their axes along the front-rear direction coincide with each other. Furthermore, the two rotating shafts 36 are positioned off-center to the lower side of the side wall 34a in the vertical direction. However, the number of rotating shafts 36 is not limited to two; there may be one or three or more.

[0023] Furthermore, the side wall 34a has an opening 37 near the center that communicates with the space inside the top section 20. The opening 37 functions as a handle when a worker carries the step stool 10. The opening 37 also prevents the bridge from unintentionally floating up when the bridge is placed in place, by allowing the bridge lift-up prevention member to be inserted into the opening 37. Furthermore, the side wall 34a has an engaging portion 38 that extends downward from its lower end. The engaging portion 38 engages with the engaged portion 53 of the base 50 when the step stool 10 is modified so that the height of the top portion 20 is reduced.

[0024] Side wall 35a is formed by hanging downward from the front end of the top plate 21, and side wall 35b is formed by hanging downward from the rear end of the top plate 21. Side walls 35a and 35b have the same structure, and only side wall 35a will be described here. The side wall 35a has a height of 100 mm to 300 mm (preferably approximately 150 mm), and its side is the exterior surface.

[0025] As shown in Figure 5, the side wall 35a has a pivot shaft 39 for supporting the rotation of the folding panel 63a of the height adjustment section 60. Here, the two pivot shafts 39 are fixed inside or within the side wall 35a at positions separated in the left-right direction such that their axes along the left-right direction coincide with each other. Furthermore, the two rotating shafts 39 are positioned off-center to the lower side of the side wall 35a in the vertical direction. However, the number of rotating shafts 39 is not limited to two; there may be one or three or more. Furthermore, the side wall 35a has an opening 40 near its center that communicates with the space inside the ceiling 20. The opening 40 prevents the bridge from unintentionally floating up when the bridge is erected, by allowing the bridge lift-up prevention member to be inserted into it.

[0026] Next, the base portion 50 will be described. The base 50 is the part that makes contact with the floor surface. The base 50 has four side walls 51a, 51b, 52a, and 52b, and four legs 55. The base 50 is surrounded by the four side walls 51a, 51b, 52a, and 52b and has a space that opens in the vertical direction. The base 50 is made of synthetic resin and is integrally molded by injection molding, and the entire structure is colored blue as the first color by mixing in a coloring agent.

[0027] The base 50 is approximately square in shape when viewed from below, with sides of 400 mm to 600 mm (preferably approximately 500 mm), and substantially matches the shape of the top 20 in plan view. The height dimension of the base 50 is 50 mm to 100 mm (preferably approximately 75 mm), which is smaller than the height dimension of the top 20.

[0028] Side wall 51a is formed to cover the internal space of the base 50 from the right side, and side wall 51b is formed to cover the internal space of the base 50 from the left side. Side walls 51a and 51b have the same configuration, and only side wall 51a will be described here. As shown in Figure 4, the side wall 51a has an engaged portion 53 at approximately the center in the front-rear direction, into which the engaging portion 38 of the top portion 20 engages.

[0029] Side wall 52a is formed to cover the internal space of the base 50 from the front, and side wall 52b is formed to cover the internal space of the base 50 from the rear. Side walls 52a and 52b have the same configuration, and only side wall 52a will be described here. As shown in Figure 5, the side wall 52a has a pivot shaft 54 ​​for supporting the rotation of the folding panel 63a of the height adjustment section 60. Here, the two pivot shafts 54 are fixed inside or within the side wall 52a at positions separated in the left-right direction such that their axes along the left-right direction coincide with each other. However, there are not limited to two pivot shafts 54; there may be only one or three or more.

[0030] The legs 55 protrude downward in a convex shape from the side walls 51a, 51b, 52a, and 52b, respectively. Specifically, as shown in Figure 6, the legs 55 are formed at the four corners of the base 50, near the vertices of the square. In a view from below, the shape of the bottom surface of the leg portion 55, including the base 56, is a composite shape of a fan-shaped structure that spreads out from the vertex of a square and a hook-shaped structure that extends in the front-to-back and left-to-right directions. In other words, the shape of the bottom surface of the leg portion 55 is included in at least the shape of the third positioning portion 28 of the top portion 20 described above. Here, the fan-shaped radius of curvature of the leg portion 55 and the fan-shaped radius of curvature of the third positioning portion 28 are approximately the same. Therefore, when stacking the base portion 50 on top of another step stool 10, the leg portion 55 fits into the third positioning portion 28, allowing the two step stools 10 to be stacked in a stable state. Furthermore, since the shape of the bottom surface of the leg portion 55 is included in the shapes of the first positioning portions 24a, 24b and the second positioning portions 25a, 26b, the leg portion 55 that protrudes downward can also be fitted into the first positioning portions 24a, 24b and the second positioning portions 25a, 26b.

[0031] Furthermore, each leg portion 55 has a base 56 on its bottom surface. The base 56 prevents slippage between the floor and the leg portion 55 by making contact with the floor surface. The base 56 is connected to the bottom surface of the leg portion 55 and protrudes downward from the bottom surface. The base 56 is made of an elastically deformable material such as rubber. As shown in Figure 6, the base 56 is positioned at the four corners of the base portion 50, near the vertices of the square. In a bottom view, the base 56 is approximately circular. Here, the diameter of the circular base 56 and the diameter of the insertion part 29 are approximately the same, and the base 56, which protrudes downward, fits into the insertion part 29 of the third positioning part 28. Therefore, when the base 50 is stacked on another step stool 10, the base 56 fits into the insertion part 29, allowing the two step stools 10 to be stacked in a stable state. Furthermore, since the shape of the leg base 56 substantially matches the shape of the insertion portion 26a of the first positioning portion 24a, the insertion portion 26b of the first positioning portion 24b, the insertion portion 27a of the second positioning portion 25a, and the insertion portion 27b of the second positioning portion 25b, the leg base 56 that protrudes downward can also fit into the insertion portions 26a, 26b, 27a, and 27b.

[0032] Next, the height adjustment section 60 will be described. The height adjustment section 60 is a part for changing the height of the top section 20. When the height of the top section 20 is low, the height adjustment section 60 is located within the internal space of the top section 20 and the internal space of the base section 50, and when the height of the top section 20 is high, it is located between the top section 20 and the base section 50. The height adjustment section 60 has support panels 61a, 61b and folding panels 63a, 63b.

[0033] In the configuration shown in Figure 5, support panel 61a is located on the right side and support panel 61b is located on the left side, with support panels 61a and 61b facing each other through the space within the height adjustment section 60. Support panels 61a and 61b are made of synthetic resin and are integrally molded by injection molding. A coloring agent is mixed in to give the entire panel a first color, such as blue. Support panels 61a and 61b have the same configuration, and this description will focus on support panel 61a. The support panel 61a is a member that supports the folding panels 63a and 63b from the inside as they fold inward. By supporting the folding panels 63a and 63b, the height of the top section 20 is maintained at a high position. The center of the support panel 61a is slightly bent inward in the vertical direction, and ribs 62 are formed along the vertical direction. The support panel 61a rotates around a pivot shaft 36 on the side wall 34a of the top section 20. Specifically, the support panel 61a rotates between a nearly vertical state in which its lower end abuts the side wall 51a from the inside, and a nearly horizontal state in which its lower end is at the same height as the pivot shaft 36. In the nearly horizontal state, the support panel 61a is located in the space within the top section 20.

[0034] In the configuration shown in Figure 4, where folding panel 63a is located at the front and folding panel 63b is located at the rear, folding panels 63a and 63b face each other via a space within the height adjustment section 60. Folding panels 63a and 63b are rotatably connected by a pivot shaft 66, with an upper panel 64 and a lower panel 65, respectively. The upper panel 64 and the lower panel 65 can be folded so that they overlap each other. The upper panel 64 and the lower panel 65 are made of synthetic resin and are integrally molded by injection molding. A coloring agent is mixed in to color the entire panel a first color, for example, blue. Folding panels 63a and 63b have the same configuration, and this description will focus on folding panel 63a.

[0035] The folding panel 63a is supported by support panels 61a and 61b to prevent its inner surface from folding inward, thereby maintaining the height of the top section 20. The upper panel 64 of the folding panel 63a is rotatably supported against the side wall 35a of the top section 20 by a pivot shaft 39. The lower panel 65 of the folding panel 63a is rotatably supported against the side wall 52a of the base section 50 by a pivot shaft 54. The folding panel 63a is constantly subjected to a force that folds it inward due to its own weight. Therefore, when the support from support panels 61a and 61b is released, the folding panel 63a folds so that the upper panel 64 and the lower panel 65 overlap each other. When the folding panel 63a is folded, it is located in the space within the top section 20 and the space within the base section 50.

[0036] In the step stool 10 configured as described above, the case of changing the height of the top 20 will be explained with reference to Figure 7. Here, as shown in Figures 4 and 5, the worker rotates the support panels 61a and 61b via the pivot shaft 36 to position them within the space inside the top 20, starting from a high position of the top 20. At this time, the support panels 61a and 61b are overlapping each other within the space inside the top 20. Next, as shown in Figure 7, the folding panels 63a and 63b, with their support released by the support panels 61a and 61b, fold inward due to their own weight. As a result, the top portion 20 and the base portion 50 can be brought into contact with each other, and as shown in Figure 1, the height of the top portion 20 can be lowered. At this time, the engaging portion 38 of the top portion 20 engages with the engaged portion 53 of the base portion 50, thereby maintaining the low height of the top portion 20. Conversely, to change the height of the top section 20 from the state shown in Figure 1 to a higher state, the engagement between the engaging portion 38 of the top section 20 and the engaged portion 53 of the base section 50 is released, and the top section 20 is lifted. By lifting the top section 20, the folded folding panels 63a and 63b are unfolded. In addition, the support panels 61a and 61b rotate under their own weight so as to intervene between the folding panels 63a and 63b, and their lower ends come into contact with the side walls 51a and 51b of the base section 50, thereby maintaining the top section 20 in a higher position.

[0037] Thus, in this embodiment, the height of the top 20, i.e., the height of the work surface F, of the step stool 10 can be changed in stages. With such a step stool 10, when standing on the edge of the work surface F, the higher the height of the top 20, the less stable the footing becomes, and the less efficient the work becomes. Also, because the work surface F of the top 20 has anti-slip protrusions 32 on its edge, the worker may mistakenly think that it is okay to stand on the edge and work. Therefore, in the step stool 10 of this embodiment, an indicator is provided on the work surface F of the top part 20 to show the worker to stand in the center of the work surface F, thereby encouraging the worker to stand in the center of the work surface F and perform their work.

[0038] The indicators will be explained in detail below. <Example 1> The indicator shown in Figure 3 is the shape of the sole 70. The shape of the sole 70 consists of a pair: the shape of the right sole 71a and the shape of the left sole 71b. The shape of the right sole 71a and the shape of the left sole 71b are each composed of a toe portion 72 and a heel portion 73 separated from each other. The shape of the sole 70 is applied to the center of the work surface F. Specifically, if the length of the front to back of the work surface F is La, the shape of the sole 70 is located within a range of La × 2 / 5 in the front to back from the center O of the work surface F, and if the length of the left to right of the work surface F is Lb, it is located within a range of Lb × 2 / 5 in the left to right from the center O of the work surface F. By being located within this range, the worker can recognize that they need to stand in the center of the work surface F. Specifically, if La and Lb are approximately 500 mm, for example, the shape of the sole 70 is located within a range of approximately 400 mm × approximately 400 mm on each side. On the other hand, the shape of the sole 70 extends beyond at least one of the following ranges: La × 1 / 5 in the front and back from the center O of the work surface F, and Lb × 1 / 5 in the left and right from the center O of the work surface F. By having a part of the shape of the sole 70 extend beyond these ranges, the shape of the sole 70 can be made more noticeable. Specifically, if La and Lb are approximately 500 mm, for example, the shape of the sole 70 extends beyond a range of approximately 200 mm × approximately 200 mm on one side. In this embodiment, if the top part 20 has a concave shape that extends downward from the work surface F and includes a housing section and connected sections 23a and 23b for housing the connecting members 22a and 22b, the shape of the sole 70 is positioned so as not to reach the housing section or connected sections 23a and 23b.

[0039] Furthermore, to ensure that workers can easily see it, the shape of the sole 70 is a second color different from the color of the periphery of the work surface F (see hatching), for example, red. That is, the area of ​​the work surface F excluding the shape of the sole 70 is the first color, and the area including the shape of the sole 70 is the second color. In this way, by limiting the color of the work surface F to only two colors, the first and second colors, the shape of the sole 70 can be made more conspicuous. Furthermore, the shape of the sole 70 is achieved by applying paint to the work surface F. The thickness of the paint film is smaller than the height of the protrusions 32. Also, if the protrusions 32 are present within the area of ​​the sole shape 70, the paint is applied to the surface of the protrusions 32 as well. Therefore, the anti-slip effect of the protrusions 32 can be maintained even within the area of ​​the sole shape 70.

[0040] Thus, since the work surface F is provided with a shoe sole shape 70 that indicates to the worker that they should stand in the center of the work surface F, the worker can recognize that they need to stand in the center of the work surface F by visually identifying the shoe sole shape 70. Furthermore, by constructing the shoe sole shape 70 with the toe portion 72 and the heel portion 73 separated, the worker can recognize it as a shoe sole shape 70 at a glance. Furthermore, the shape of the sole 70 is not limited to cases where the paint is applied to the work surface F. For example, a separate component formed in the shape of a shoe sole 70 may be fixed to the work surface F. Specifically, a concave recess is formed in the work surface F in the shape of a shoe sole, extending downward from the work surface F, and the separate component formed in the shape of a shoe sole 70 is fitted into the recess. At this time, the separate component formed in the shape of a shoe sole 70 and the recess may be fixed, for example, with screws or adhesive, or by snap-fit ​​engagement. When the separate component formed in the shape of a shoe sole 70 is fixed to the recess, the surface of the separate component and the work surface F are substantially flush. The surface of the separate component formed in the shape of a shoe sole 70 also has anti-slip protrusions 32. The separate component formed in the shape of a shoe sole 70 is made of synthetic resin and is molded by injection molding. In this way, by making the shoe sole shape 70 a separate component, the shoe sole shape 70 can be easily made in different colors. Also, the shoe sole shape 70 can be easily applied to the work surface F. Furthermore, the shape of the sole 70 may be made of separate components for the toe portion 72 and the heel portion 73, or they may be connected. Also, by making the shape of the right sole 71a symmetrical with respect to the center line of the shoe width, it can be made common with the shape of the left sole 71b.

[0041] Alternatively, for example, a separate component formed in the shape of a shoe sole 70 in sheet form may be attached to the work surface F. In this case, a concave recess is formed in advance from the work surface F in the shape of a shoe sole, and the sheet formed in the shape of a shoe sole 70 is fitted into the recess. At this time, the sheet formed in the shape of a shoe sole 70 and the recess can be bonded together, for example, with an adhesive or with the adhesive layer of the sheet itself. In this way, by making the shape of a shoe sole 70 into a sheet, the shape of the shoe sole 70 can be easily made into a different color. Also, the shape of a shoe sole 70 can be easily applied to the work surface F. Furthermore, the shape of the sole 70 may be indicated by showing only the outline of the sole with a line of a predetermined thickness in a second color, while the inside of the outline of the sole may be the same first color as the periphery.

[0042] <Example 2> Next, we will explain the indicators related to Example 2. The indicator shown in Figure 8 is the shape of the sole 74. The sole shape 74 consists of a pair of shapes: the shape of the right sole 75a and the shape of the left sole 75b. The shape of the right sole 75a and the shape of the left sole 75b are approximately elliptical or oblong, respectively. The method of applying the sole shape 74 to the work surface F and the color of the sole shape 74 can be applied in the same manner as in Example 1.

[0043] <Example 3> Next, we will explain the indicators related to Example 3. The indicator shown in Figure 9 is a circular shape 76. The circular shape 76 is applied to the center of the work surface F. Specifically, the circular shape 76 is a circle that is larger than Lc × 1 / 4 and smaller than Lc × 1 / 2 from the center O of the work surface F, when one of the lengths of the front-to-back length and the left-to-right length of the work surface F is Lc. It is preferable that the circular shape 76 is formed so as not to extend to the housing portion or connected portion 23a, 23b, which are formed in a concave shape downward from the work surface F and house the connecting members 22a, 22b.

[0044] Furthermore, to ensure that workers can easily see it, the circular shape 76 is a second color, different from the color of the periphery of the work surface F, for example, red. That is, the area of ​​the work surface F excluding the circular shape 76 is the first color, and the area including the circular shape 76 is the second color. In this way, by limiting the work surface F to only two colors, the first and second colors, the circular shape 76 can be made more conspicuous. Similar to Example 1, the circular shape 76 can be formed by applying paint to the work surface F, attaching it as a separate component from the top part 20, or attaching it as a sheet. Furthermore, the circular shape 76 may be formed by indicating only the circular outline with a second color and a predetermined thickness, while the area inside the circular outline is the same first color as the periphery. It is also preferable to have anti-slip protrusions 32 both within and outside the area of ​​the circular shape 76.

[0045] <Example 4> Next, we will explain the indicators related to Example 4. The indicator shown in Figure 10 is a rectangular shape 77. The rectangular shape 77 is applied to the center of the work surface F. The rectangular shape 77 is similar in shape to a square or the shape of the work surface F in plan view. Alternatively, the rectangular shape 77 is a rectangle in which one side is larger than Ld × 1 / 2 and smaller than Ld × 4 / 5, when one of the lengths of the front-to-back length and the left-to-right length of the work surface F is Ld. The center O of the work surface F and the center of the rectangular shape 77 are approximately coincident. Preferably, the rectangular shape 77 is formed so as not to extend to the housing portion or connected portion 23a, 23b, which are formed in a concave shape downward from the work surface F and house the connecting members 22a, 22b.

[0046] Furthermore, to ensure that workers can easily see it at a glance, the rectangular shape 77 is a second color, different from the color of the periphery of the work surface F, for example, red. That is, the area of ​​the work surface F excluding the rectangular shape 77 is the first color, and the area containing the rectangular shape 77 is the second color. In this way, by limiting the work surface F to only two colors, the first and second colors, the rectangular shape 77 can be made to stand out. Similar to Example 1, the rectangular shape 77 can be formed by applying paint to the work surface F, attaching it as a separate component from the top part 20, or attaching it as a sheet. Furthermore, the rectangular shape 77 may be formed by indicating only the outline of the rectangle with a second color and a predetermined thickness, while the area inside the outline of the rectangle is the same first color as the periphery. It is also preferable to have anti-slip protrusions 32 both within and outside the area of ​​the rectangular shape 77.

[0047] <Example 5> Next, we will explain the indicators related to Example 5. The indicator shown in Figure 11 is a pattern 78 applied to the periphery of the work surface F. The pattern 78 is applied to the periphery of the work surface F, at each of the four corners. Specifically, the pattern 78 is roughly L-shaped or hook-shaped. When one of the lengths of the front-to-back length and the left-to-right length of the work surface F is Le, the pattern 78 is applied to the outside of a rectangle whose side is greater than Le × 1 / 2 and smaller than Le × 4 / 5, and whose center coincides with the center O of the work surface F. Note that, as shown in Figure 3, if there is a positioning section 28 formed in a concave shape downward from the work surface F, the pattern 78 may be applied closer to the center O, avoiding the positioning section 28.

[0048] Furthermore, so that workers can easily see the pattern 78, the pattern 78 is a second color different from the color of the central part of the work surface F, for example, red. That is, the area of ​​the work surface F that does not have the pattern 78 is the first color, and the area with the pattern 78 is the second color. In this way, by limiting the work surface F to only two colors, the first color and the second color, the central part that does not have the pattern 78 can be made to stand out. As in Example 1, the pattern 78 can be applied by painting paint onto the work surface F, attaching it as a separate component from the top part 20, or attaching it as a sheet. Alternatively, the pattern 78 may be represented only by its outline using a second color and a predetermined thickness, with the area inside the outline of the pattern being the same first color as the central part.

[0049] <Example 6> Next, we will explain the indicators related to Example 6. The indicator shown in Figure 12 is a pattern 79 applied to the periphery of the work surface F. The pattern 79 is applied to the periphery of the work surface F, at each of the four corners. Specifically, the pattern 79 is roughly grid-like. When the length of the work surface F is one of its lengths, Lf (front-to-back length and left-to-right length), the pattern 79 is applied to the outside of a rectangle whose side is greater than Lf × 1 / 2 and smaller than Lf × 4 / 5, and whose center coincides with the center O of the work surface F. Note that, as shown in Figure 3, if there is a positioning section 28 formed in a concave shape downward from the work surface F, the pattern 79 may be applied closer to the center O, avoiding the positioning section 28.

[0050] Furthermore, to ensure that workers can easily see the pattern 79, the grid lines forming the pattern are of a predetermined thickness, and these lines are painted in a second color, such as red, that is different from the color of the central part of the work surface F. The areas between the grid lines are painted in the same first color as the central part. By limiting the colors of the work surface F to only two colors, the first and second colors, the central part, where the pattern 79 is not applied, can be made more conspicuous. As in Example 1, the pattern 79 can be applied by painting paint onto the work surface F, attaching it as a separate component from the top part 20, or attaching it as a sheet.

[0051] As described above, by providing an indicator on the work surface F that shows the worker to stand in the center of the work surface F, it is possible to make the worker stand in the center of the work surface F while working. Therefore, even if the height of the top part 20 is changed to a higher position, the worker will be inclined to work in the center, so they can work in a stable position. Furthermore, since the work surface F has different colors applied to its center and periphery, workers can easily see the indicators at a glance. Because the work surface F has only two colors applied, the indicators are made more conspicuous.

[0052] Although the present invention has been described above with reference to the embodiments described above, the present invention is not limited to the embodiments described above, and modifications can be made within the scope of the present invention, and each embodiment and each example may be combined. In the embodiment described above, the shape of the third positioning portion 28 formed at the four corners of the top portion 20, which are near the vertices of the square in a plan view, was described as a composite shape of a fan-shaped shape spreading out from the vertices of the square and a hook-shaped shape extending in the front-to-back and left-to-right directions. However, it is not limited to this case, and may be roughly fan-shaped or roughly rectangular. Similarly, the shape of the leg portion 55 may also be roughly fan-shaped or roughly rectangular.

[0053] In the embodiments described above, the case in which the height adjustment unit 60 has support panels 61a, 61b and folding panels 63a, 63b was described, but it is not limited to this case. The height adjustment unit 60 can have any configuration as long as the height of the top part 20 can be changed in steps. In the embodiment described above, the approximately circular shape includes polygons that can be recognized as circular by the worker. [Explanation of Symbols]

[0054] 10: Step stool 20: Top part 21: Top plate 70: Shoe sole shape 74: Shoe sole shape 76: Circular shape 77: Rectangular shape 78: Pattern 79: Pattern

Claims

1. A step stool having a top part with a work surface and a base part that contacts the floor, wherein the height of the work surface is adjustable, A step stool characterized in that the work surface is marked with an indicator to show the worker where to stand in the center of the work surface.

2. The step stool according to claim 1, characterized in that the central part of the work surface and the peripheral part of the work surface are colored differently as indicators.

3. The work surface is coated with only two colors: a first color and a second color different from the first color. The step stool according to claim 2, characterized in that, as the indicator, the periphery of the work surface is coated with the first color and the central part of the work surface is coated with the second color.

4. The step stool according to any one of claims 1 to 3, characterized in that, as the indicator, the shape of the sole of a shoe is applied to the central part of the work surface in a color different from the color of the peripheral edge of the work surface.

5. The step stool according to claim 4, characterized in that both the surface shaped like the sole of the shoe and the surface other than the sole of the shoe have a plurality of anti-slip protrusions.

6. The step stool according to any one of claims 1 to 3, characterized in that, as the indicator, a circular or rectangular shape is provided in the center of the work surface in a color different from the color of the periphery of the work surface.

7. The step stool according to claim 6, characterized in that both the circular or rectangular surface and the surface other than the circular or rectangular surface have a plurality of anti-slip protrusions.

8. The step stool according to any one of claims 1 to 3, characterized in that the periphery of the work surface is decorated with a pattern of a different color from the color of the central part of the work surface.

9. The step stool according to claim 8, characterized in that the work surface is substantially square in plan view, and the pattern is applied to the four corners of the work surface.

Images