TECHNICAL FIELD
The present disclosure relates to a simplified staircase that can be easily installed on a sloping surface such as a mountain slope or a slope land.
BACKGROUND
A conventional mountain road staircase typically includes two flexible long girder supports, a plurality of girders fixed at regular intervals in the longitudinal direction between them, and a plurality of piles that fix the girder to the ground.
SUMMARY
With regard to this type of the simplified staircase, there is a request to prevent slipping between the shoes of the person going up and down the stairs and the girder. In particular, it is desirable that it is difficult to slip even if the surface of the girder or the sole of the user's shoe is wet or snow or mud is attached due to snowfall and rain. In particular, it is desirable to prevent slipping, especially when a person goes down the stairs. Furthermore, it is desirable to have the ability to use on slopes with a steeper slope than conventional products. One objective of the present disclosure is to increase the ability to avoid occurrence of slipping between a shoe and a girder in a simplified staircase.
Another objective is to provide a simplified staircase applicable to a steeper slope.
Other objectives of the present disclosure will be clarified from the following description.
In one aspect of the present disclosure, a simplified staircase that is installed on a sloping ground includes: a plurality of girders that form a plurality of steps; one or more longitudinal connecting members that connect the plurality of girders in a vertical direction at intervals; a plurality of fixing piles that fix the plurality of girders to the sloping ground. At least one of the plurality of girders includes: one or more first protrusions that protrude from a front side of an upper surface of the at least one of the plurality of girders; and one or more second protrusions that protrude from a rear side of the upper surface of the at least one of the plurality of girders. The one or more second protrusions are higher than the one or more first protrusions in height.
According to one embodiment, one or more second processes are larger than one or more first processes in lateral dimensions.
According to one embodiment, one or more second processes are larger than one or more first processes in longitudinal dimensions.
According to one embodiment, one or more first processes or one or more second processes are elongated and wavy in the lateral direction in a planar view.
According to one embodiment, the at least one girder is a cylinder for receiving the arch or heel portion of the sole of a person going up and down a simplified staircase, and a first half of the sole of a person climbing a simplified staircase. One or more first protrusions are erected on the upper surface of the bridle, and one or more second protrusions are erected on the upper surface of the cylinder.
According to one embodiment, one or more second protrusions are erected in the vicinity of the rear end of the upper surface of the cylinder.
According to one embodiment, the upper surface of the cylinder portion is curved in an arc shape at the side view and bulges upward from the upper surface of the bridle.
According to one embodiment, a simplified staircase in which the first half from the highest point on the upper surface of the cylinder to the boundary with the brass portion is inclined in the posterior upward direction with respect to the upper surface of the brass portion.
According to one embodiment, one or more longitudinal connecting members are attached to each girder by means of a fixing pile without using a separate fixture.
According to one embodiment, the girder has a horizontal coupling mechanism for transversely connecting with other girders.
BRIEF DESCRIPTION OF DRAWING
FIG. 1 is a perspective view showing a simplified staircase according to one embodiment installed on a sloping ground.
FIG. 2 is a perspective view of the girder of the simplified staircase seen from the upper right front diagonally.
FIG. 3 is a perspective view of the girder from the upper left front side.
FIG. 4 a plan view of the girder.
FIG. 5 a left-side view of the girder.
FIG. 6 is a right-side view of the girder (an example of the positional relationship with the shoe when the user climbs the stairs is also shown).
FIG. 7 is a right-side view of the girder (an example of the positional relationship with the shoe when the user descends the stairs is also shown).
FIG. 8 is a front view of the girder.
FIG. 9 is a rear view of the girder.
FIG. 10 is a bottom view of the girder.
FIG. 11 is a photograph and explanatory diagram of the structure of connecting two girders horizontally from the bottom.
FIG. 12 is a plan view of a longitudinal connecting member according to a modification.
FIG. 13 is a left-side view showing an example of a configuration in which a longitudinal connecting member is attached to a girder using a fixed pile.
DESCRIPTION OF EMBODIMENT
Hereinafter, one embodiment of the present invention will be described.
As shown in FIG. 1, the simplified staircase 1 according to one embodiment is installed on a sloping ground 2 such as a mountain trail, a steel tower patrol path, or a slope, for example. In the following description, when expressing the positional relationship or direction of the simplified staircase 1 and its parts, the front, back, right, left, upper and lower directions or sides from the perspective of the person climbing the simplified staircase 1 are referred to as “front”, “back”, “right”, “left”, “up” and “down” directions or sides. In addition, the left and right directions are the “horizontal” direction, the front and rear directions are the “vertical” direction, and the upper and lower directions are the “vertical” direction.
The simplified staircase 1 includes a plurality of girders 3 that form a plurality of steps of the staircase, one or more (for example, a left and right pair) longitudinal connecting member 5 that interconnects the girders 3 of different steps in the longitudinal direction, and each girder 3 is fixed to the ground 2.
The girder 3 is a horizontal column-shaped object, and is installed on the ground 2 in a posture in which the longitudinal direction is almost identical in the lateral direction. The girder 3 has sufficient strength and rigidity required for outdoor stairs, and has weather resistance that can withstand wind and rain. It is desirable that the girder 3 be as light as possible and have a low cost so that it can be easily carried by a person. In consideration of these conditions, the girder 3 is made, for example, of FRP (fiber reinforced plastic), and is manufactured as an integral product by mold molding, for example, but the material and manufacturing method are not limited thereto.
Each girder 3 is fixed to the ground 2 using, for example, a pair of fixed piles 7 on the left and right. That is, there is a first through hole 19 (see FIG. 4)) at two locations near the left end and near the right end of the rear of the girder 3, and two fixing piles 7 are inserted into the two first through holes 19. These fixed piles 7 are shot into the ground with a hand hammer to the maximum depth. The head 7A of the fixing pile 7 is larger than the inner diameter of the first through hole 19, and the head 7A presses the girder 3 against the ground 2, thereby fixing the girder 3 to the ground 2. The surface of the portion that enters the ground of the fixing pile 7 has many convex or concave parts (not shown), and these convex or concave portions make it difficult for the fixing pile 7 to escape from the ground. It is desirable that the fixed pile 7 has sufficient strength and rigidity that can penetrate or break the roots of trees and rocks in the ground, and that it is not easy to corrode or deteriorate. In consideration of such conditions, the fixing pile 7 is, for example, made of anti-rust treatment or rust-resistant steel, but the material is not limited thereto.
One or more, for example, a pair of left-right and left-right longitudinally connected members 5, connect a plurality of girders 3 of different floors longitudinally at arbitrary intervals. Each longitudinal connecting member 5 is, for example, an elongated rod or rope, for example, having a length of about 5 meters to about 10 meters, is arranged longitudinally on the sloping ground 2, and is fixed to a plurality of girders 3. That is, there is a second through hole 23 (see FIG. 4) at two locations near the left edge and near the right edge of the front part of each girder 3. A component for fixing each longitudinal connecting member 5 is attached to each of the two second through holes 23, and each longitudinal connecting member 5 is fixed to the component. A comparative method, for example, as shown in FIG. 8 described above, can be used for this fixing method. According to this method, the J-shaped hook bolt is inserted into the second through hole 23 so that the spiral portion of the screw part goes upward from the second through hole 23 and the hook portion exits downward from the second through hole 23. Then, by tightening the nut screwed to the screw portion of the hook bolt, the vertical connecting member 5 is firmly fixed between the hook portion and the lower surface of the girder 3.
The form of each longitudinal connecting member 5 is not limited to an elongated rod or a rope shape. For example, the vertical connection member 5 may be a net-shaped or perforated sheet-shaped component as shown in FIGS. 1 to 3 disclosed in JP H03-049136 U, which is incorporated herein by reference. In that case, as in the fixing method, the longitudinal connecting member 5 may be fixed to the girder 3 by a fastener using a spiral bolt inserted into the second through hole 23. In FIGS. 1 to 3 of JP H03-049136 U, two longitudinal connecting members in the form of a net or a perforated sheet are connected to a plurality of girders, but instead of this, the width of one net-shaped or perforated sheet-shaped longitudinal connecting member is wider than that the above-described comparative example.
The longitudinal connection member 5 maintains a constant positional relationship (spacing) between the plurality of girders 3. Further, even if a part of the soil on the sloping ground 2 is washed away or collapsed by running water or the like, the vertical connection member 5 connects the plurality of girders 3 to the other girder 3 to prevent it from being washed away or falling together with the soil.
The longitudinal connecting member 5 has sufficient strength, rigidity, and weather resistance for the above purpose. Further, since it is necessary to curve the simplified staircase 1 in the curved ramp, it is desirable that the vertical connecting member 5 has some degree of flexibility and can be curved. Further, it is desirable that the longitudinal connecting member 5 be as light as possible and low cost so that it can be easily carried by a person. In consideration of such conditions, the longitudinal connecting member 5 is, for example, made of FRP (fiber reinforced plastic), but the material is not limited thereto.
Hereinafter, with reference to FIGS. 2 to 11, the girder 3 will be described in more detail.
As shown in FIG. 4, the lateral dimension (length) L1 of the girder 3 is a value that is almost the lowest as the width of the stairs on which a person goes up and down, for example, about 40 cm to about 60 cm (for example, 50 cm). The longitudinal dimension (depth) D1 of the girder 3 is approximately the lowest value in order to prevent a person climbing the stairs from stepping on the girder 3 with a shoe and not slipping, for example, about 8 cm to about 12 cm (for example, about 10 cm) (that is, about one-third to about one-half of the vertical dimension of an adult general shoe). As shown in FIG. 5, the vertical dimension (height) H1 of the girder 3 is a value that is almost the lowest as the height of one step of the staircase, for example, about 7 cm to about 12 cm (for example, about 9 cm).
The girder 3 has a cylinder portion 11 and a brass part 13, and they are made as an inseparable integrated product by, for example, mold molding. As can be seen from FIGS. 1, 2, 5 and 6, the cylinder portion 11 is a hollow abbreviated cylindrical object with closed left and right ends (the longitudinal short diameter of the substantially elliptical cross-section is, for example, about 7 cm to about 8 cm, and the vertical long diameter is, for example, about 10 cm to about 13 cm) It has a shape that looks like a part corresponding to about one-third of the area of the lower front side has been excised in the lateral view.
As shown in FIG. 4, a first through hole 19 is provided at each of the two locations near the left and right ends of the cylinder portion 11. Around each first through hole 19, a pocket 21 having a flat bottom surface is formed by concave downward from the upper surface 11A of the cylinder portion 11. The pocket 21 accommodates the head of the fixed pile 7 inside it so that the head does not protrude above the upper surface 11A of the cylinder 11.
The surface 35 (FIG. 5) corresponding to the inclined cut surface of the cylinder portion 11 is a contact plane that is in contact with the inclined ground 2. The cylinder 11 corresponds to a part of the riser board, the step nose, and the treads (a portion close to the step nose) in a general staircase. The external shape of the elliptical column of the cylinder section 11 imitates the log wood that has been used for a long time as a primitive simplified staircase, and it is easy to harmonize with the landscape of the mountainous area.
As shown in FIGS. 6 and 7, the cylinder 11 is most often stepped on by the arch or heel portion of the bottom of the shoe 61 of a person going up and down the simplified staircase 1.
The girder 3 has a certain dimension from the front end near the upper part of the cylinder portion 1 to the front end near the top of the cylinder portion 1 over almost the entire length of the girder 3, for example, about 3 cm to 5 cm (for example, 3.5 cm). The brass 13 corresponds to a part of the treads in a general staircase (that is, a flat portion separated from the step nose, for example, about 6 cm to about 12 cm forward, or for example, about 7 cm to about 10 cm).
As shown in FIG. 4, a second through hole 23 is provided at each of the two locations near the left and right ends of the brass portion 13. Around each second through hole 23, a pocket 25 having a flat bottom surface is formed by concave downward from the upper surface 13A of the brass portion 13. The bottom surface of the pocket 25 provides a seat surface for fixing the longitudinal connecting member, such as a tightening nut of the hook bolt described above or the head of the screw bolt described above.
As shown in FIG. 6, in most cases, the bell 13 is directly under the toe ball (the base of the fifth toe of the foot) 65 from the ball of the toe to the ball of the small toe of the foot 63 of the person climbing the simplified staircase 1 (the part where a large load and kicking force are applied when climbing), in short, the first half of the sole (the part in front of the arch).
As can be seen from FIG. 5, the upper surface 13A of the brass portion 13 is a plane. When the inclination angle with respect to the horizontal direction 41 of the inclined ground 2 on which the girder 3 is installed is a predetermined angle θ (for example, about 30 degrees to about 45 degrees, for example, about 35 degrees), the upper surface of the brass portion 13A is horizontal. At the bottom of the front end of the bridle 13, there is a contact patch 37 that is in contact with the sloping ground 2. The ground patch 37 of the brass portion 13 is located on an extension of the contact patch 35 of the cylinder portion 11.
As shown in FIG. 5, the upper surface 11A of the cylinder portion 11 is curved in an arc shape in the side view, and a predetermined height H2 (for example, about 10 mm to about 30 mm, for example, about 15 mm) expands upward from the upper surface 13A of the brass portion 13. Therefore, the portion located in the vicinity of the boundary line with the upper surface 13A of the cylinder portion 11A is inclined at a predetermined angle q (for example, about 10 degrees to about 30 degrees, for example, about 20 degrees) with respect to the upper surface 13A of the cylinder. When the upper surface 13A of the brass portion is horizontal, the first half 11B of the upper surface 11A of the cylinder portion (the portion close to the upper surface 13A of the cylinder) is inclined upward and backward from the horizontal.
The above-described upward bulge of the upper surface of the cylinder 11A and the inclination of the first half 11B upward and backward are the shoes of the person descending the simplified staircase 1. Further, the bulging and inclination of the upper surface 11A of the cylinder portion makes it possible to install the girder 3 on a sloped ground 2 that is steep by a slight angle (an angle smaller than the predetermined angle q for example, about 10 degrees) than the inclination angle θ (for example, about 40 degrees) shown in FIG. That is, when the girder 3 is installed on such a steep sloping ground 2, the upper surface of the brass 13A tilts upward forward, but the first half 11B of the upper surface 11A of the cylinder provides a horizontal scaffolding.
As shown in FIG. 4, on the upper surface 13A of the brass portion 13, a plurality of small protrusions 17 are erected at intervals in the horizontal and longitudinal directions at a plurality of locations over the substantially entire length of the brass portion 13 (the area excluding the pockets 25 and 25 at both ends). As can be seen from FIGS. 2 to 4, the small processes 17 are arranged in a plurality of rows (e.g., 10 columns) in the horizontal direction and a plurality of rows (in the vertical direction (e.g., 2 rows). Each small protrusion 17 is a horizontal shape in planar view, and its lateral dimension is longer than the longitudinal dimension. For example, the thickness of the planar view of the small protrusion 17 is, for example, about 3 mm to about 7 mm (for example, about 4 mm), the vertical dimension with curvature is, for example, about 7 mm to about 12 mm (for example, about 10 mm), and the horizontal dimension is, for example, about 20 mm to about 40 mm (for example, about 30 mm). The height of each small protrusion 17 is about 3 mm to about 7 mm (for example, about 4.5 mm). Further, each small protrusion 17 is bent into a wave shape in a planar view, and has a portion extending in the lateral direction and a portion extending in an oblique direction with respect to the lateral direction.
A plurality of small protrusions 17 on the upper surface 13A of the brass part serve to prevent slipping between the person's shoes and the girder 3, especially when a person climbs the simplified staircase 1. As described above, as shown in FIG. 6, a person who climbs the staircase 1 often steps on the brim 13 in the first half of the sole, and adds a kicking force to the first half of the sole to move forward. In order to transmit its kicking force to the ground, the first half of the sole of many shoes has a slip inhibition irregularity. The laterally elongated and wavy curved shape of the plurality of small processes 17 on the upper surface of the brass 13A, their relatively small longitudinal dimensions, and the plurality of rows and plurality of rows allow the small processes 17 to engage with the irregularities of the first half of the sole, making it difficult to slip longitudinally and slip laterally of the shoe 61. Thus, the small protrusion 17 on the upper surface 13A of the brass mainly suppresses slip between the shoe 61 of the person climbing the stairs 1 and the girder 3.
The gaps between the small protrusions 17 provide a way for mud, soil, snow, etc. to flow out of the upper surface of the brass 13A when mud, soil, snow, etc. are placed on the upper surface 13A, thereby suppressing mud, soil, snow, etc. from stopping on the upper surface of the brass 13A. This action also helps to suppress slip between the shoe 61 and the girder 3.
As can be seen from FIGS. 4-7, in the vicinity of the rear end of the cylinder portion 11 descending slightly posterior downward from the top of the upper surface 11A of the cylinder portion 11, a plurality of large protrusions 15 are erected at intervals in the horizontal direction in a plurality of places over the substantially entire length of the cylinder portion 11 (the area excluding the pockets 21 and 21 at both ends). As can be seen from FIGS. 2 to 7, each large protrusion 15 on the upper surface 11A of the cylinder is larger than each small protrusion 17 on the upper surface 13A of the brass in horizontal dimensions, vertical dimensions, and height (for example, about 1.3 times to about 3 times larger, and the height is particularly significantly about 3 times larger). A plurality of (e.g., 6) large protrusions 15 are arranged in a row in the transverse direction. Each large protrusion 15 is a horizontal shape in planar view, and its lateral dimension is larger than the longitudinal dimension. For example, the thickness of the planar view of the large protrusion 15 is, for example, about 3 mm to about 7 mm (for example, about 5 mm), the vertical dimension including curvature is, for example, about 10 mm to about 20 mm (for example, about 15 mm), and the horizontal dimension is, for example, about 45 mm to 70 mm (for example, about 55 mm). The height of each protrusion 16 is, for example, about 10 mm to about 20 mm (for example, about 15 mm). Further, each large protrusion 15 is bent in a wavy shape in a planar view, and has a portion extending in the transverse direction and a portion extending in an oblique direction with respect to the transverse direction.
A plurality of large protrusions 15 on the upper surface 11A of the cylinder serve to prevent slipping between the person's shoe 61 and the girder 3 when a person ascends and descends the simplified staircase 1. As described above, as shown in FIG. 6, a person who climbs the staircase 1 usually steps on the tube 13 at the arch of the sole of the shoe or a portion near it. Further, as shown in FIG. 7, a person going down the stairs 1 usually steps on the tube 13 at the heel of the sole. Therefore, when going up or down stairs, the plurality of large protrusions 15 on the upper surface 11A of the tube are usually in contact with the arch or heel portion of the sole. The arch of the sole of many shoes is relatively large and concave upward, and the heel part has an unevenness of slip suppression. The high height as described above by a plurality of large protrusions 15 on the upper surface of the cylinder 11A allows the large protrusions 15 to engage with the large concave arch portion of the sole and the unevenness of the heel portion, thereby suppressing the longitudinal slip of the shoe 61. Further, the shape of the corrugated shape of the large protrusion 15 also suppresses the lateral slip of the shoe 61.
Furthermore, in the unlikely event that the heel portion of the shoe 61 of a person going down the stairs 1 slips on the tube 11 and flows backward (forward for that person), the flowing heel portion is received by a large protrusion 15 that rises high from the upper surface of the cylinder 11A. Since the large protrusion 15 is a relatively large size as described above, it has a large strength, and even if the heel part of the shoe 61 collides with it with a strong force, it withstands the impact and firmly holds the heel portion.
Referring to FIG. 4, the lateral spacing (gap width) S of the plurality of large protrusions 15 and 15 is wide enough to flow mud and snow on the upper surface of the cylinder 11A to the outside of the cylinder 11. Thereby, as described above, when the heel portion of the shoe 61 of a person going down the stairs 1 slips, the heel portion receives the large protrusion 15 and 15 with a high degree of certainty. Considering the size of children's shoes as well as adults, the distance S of the gap between the large protrusions 15 and 15 is preferably about 1 cm to about 5 cm, for example, more preferably about 1 cm to about 3.5 cm.
As can be seen from FIGS. 3, 8 and 10, a plurality of reinforcing ribs 51 are provided on the inner surface of the girder 3 to increase strength while reducing the overall weight of the girder 3.
As can be seen from FIGS. 3 and 8, the left and right two first through holes 19 of the girder 3 are each defined by a linearly extending cylinder wall 31 having a length close to the total height H1 of the girder 3. These two cylinder walls 31 constantly regulate the direction of the fixing piles 7 inserted into the two first through holes 19.
As can be seen from FIGS. 2 to 12, the two walls at both ends of the girder 3 in the horizontal direction are each provided with a connecting mechanism for connecting the girder 3 to another girder 3 in the horizontal direction without gaps. The transverse connection mechanism includes an engagement convex portion 27 and an engaged recess 33. For example, an engagement convex portion 27 is provided on the leftmost wall of the girder 3, and an engagement recess portion 33 is provided on the rightmost wall. In the central portion of the engagement convex portion 27, a bolt through hole 29 that transversely penetrates the engagement convex portion 27 is drilled. In the central portion of the engagement recess 33, a bolt through hole 34 that transversely penetrates the engagement recess 33 is drilled.
The engagement convex portion 27 protrudes in the right direction from, for example, the outer surface of the left end wall of the girder 3. The shape of the engagement convex portion 27 is a trapezoidal column extending in the vertical direction, and when viewed as a plane, it is a trapezoidal shape whose dimension expands as it goes to the right. The engagement recess 33 is recessed in the left direction from the outer surface of, for example, the rightmost wall of the girder 3. The shape of the engagement concave portion 3 corresponds to the shape of the engagement convex portion 27. Therefore, by inserting the engagement convex portion 27 of the girder 3 into the engagement recess 33 of the other girder 3 in the vertical direction, there is practically no gap between them, and even if they are pulled in the lateral direction, the two are not separated.
As shown in FIG. 12, when the engagement convex portion 27 of one girder 3 and the engagement recess 33 of the other girder 3 are completely engaged, the bolt through hole 29 in the engagement convex portion 27 and the bolt through hole 34 in the engagement recess 33 are communicated in a straight line. Then, by inserting the connecting bolts 53 into the bolt through holes 29 and 34 and tightening the nut 55, the engagement convex portion 27 and the engagement recess portion 33 are firmly fastened. Thus, the two girders 3 and 3 are connected in the horizontal direction, and the width of the staircase 1 is enlarged by 2 times. In the same way, if the three or more girders 3 and 3 are connected in the horizontal direction, the width of the staircase 1 can be enlarged by 3 times or more.
FIG. 12 shows a longitudinal connection member 71 that applies to a modification. FIG. 13 shows an example of a method of longitudinally connecting the girder 3 to the girder 3 on another floor using the longitudinal connecting member 71.
As shown in FIG. 12, the longitudinal connecting member 71 according to the modification is an elongated rod or rope, and is made of a robust and flexible material such as FRP. The total length of the longitudinal connecting member 71 corresponds to the maximum allowable distance between the two girders 3 and 3 arranged in the vertical direction (for example, about several tens of cm to about 1 m). A plurality of (for example, three) pile engagement rings 73 are provided at different positions in the longitudinal direction at the front end of the longitudinal connecting member 71, and a plurality (for example, two) pile engagement rings 73 are also provided at the rear end at different positions in the longitudinal direction. When the fixing pile 7 is inserted into the central hole of each pile engagement ring 73, the inner surface of the central hole is in contact with the outer surface of the fixing pile 7 with appropriate pressure. Due to the frictional force between the pile engagement ring 73 and the fixing pile 7, the longitudinal connecting member 71 does not detach from the fixing pile 7 unless a person tries to pull it out of the fixing pile 7 with a fairly strong force.
As shown in FIG. 13, when one girder 3 is fixed to the ground with a fixing pile 7, the fixing pile 7 is inserted into one pile engagement ring 73 at the front end of the longitudinal connecting member 71 from another girder 3 (omitted) next to the rear, and at the same time, another vertical connecting member 71 from another girder 3 (omitted) next to the front By inserting it into one pile engagement ring 73 at the rear end of another longitudinal connecting member 71, 71 is attached to the girder 3. At this time, since it is not necessary to fix the vertical connecting member 71 to the girder 3 separately using another component, the installation work of the simplified staircase 1 is simplified. The distance between the two girders 3 and 3 can be adjusted in a plurality of stages by selecting the pile engagement ring 73 through which the fixed pile 7 is passed.
In addition, when the fixing pile 7 is used for both the purpose of fixing the girder 3 and fixing the longitudinal connecting member as described above, instead of the longitudinal connecting member 71 having a length between the adjacent girders 3 and 3 shown in FIG. The longer longitudinal connecting member has a plurality of pile engagement rings 73 as shown in FIG. 12 not only at both ends but also throughout the middle. In this case as well, the spacing between the girders 3 can be changed by selecting the pile engagement ring 73 that engages the fixed pile 7.
As a further modification, as shown in FIGS. 1 to 3, one or more longitudinal connecting members in the form of a net or a perforated sheet are used.
The simplified staircase according to one embodiment described above and its components are illustrative examples only. The present invention can be implemented in a variety of different aspects without departing from the gist thereof.
Patent Application
20250198164
