JPH0328488A - Ladder made of rubber - Google Patents

Abstract

PURPOSE:To improve stability and impact resistance by a method wherein a ladder installed to a quay is formed such that a side pillar part and a step part are both made of rubber, and a flexible core having both ends reinforced with a rigid material is embedded in a step member. CONSTITUTION:A pair of pillar members 2 made of cylindrical rubber are secured to a quay, and step members 3 are mounted at equal intervals therebetween to form a ladder 1. In the step member 3, both ends of a flexible member 9b, e.g. a wire rope, are formed such that a core 9 reinforced with a rigid material 9a is covered with rubber. Even when an impact is exerted due to collision of a ship therewith, a whole is resiliently deformed, and a permanent strain is prevented from remaining. This constitution provides a ladder which is excellent in stability during climbing up and down of the ladder and increases a life.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field in Icheon] The present invention relates to a rubber ladder suitable for use on barge quays, etc.

[Conventional technology]

Conventionally, iron ladders have been used as ladders for use on quays of barges, etc. However, iron ladders are susceptible to permanent deformation due to impacts from ship collisions or falling objects, and once permanent deformation occurs, they cannot withstand repeated use. Therefore, iron ladders used on quay walls and the like have a drawback of having an extremely short lifespan.

In order to eliminate these drawbacks of iron ladders, Utility Model Publication No. 63-48800 proposes a cylindrical fender shape with a pair of parallel side pillars formed of rubber and integrally formed of the same rubber. Connected at regular intervals by multiple horizontal bars,
A quay ladder is shown buried inside this pier with tension members such as chains fixed at both ends inside the side pillars, slightly loosened. This ladder's side pillars have the same structure as fenders, so they act as a buffer against ship collisions, preventing permanent deformation and damage. Since it is buried in the yellow beam in a loose state, it has the effect of being able to flexibly follow the distance between the side columns on both sides when it widens or narrows due to a ship collision.

[Problem to be solved by the invention]

As mentioned above, the ladder described in Utility Model Publication No. 63-48800 eliminates the disadvantages of conventional iron ladders in that it prevents permanent deformation and extends the life of the ladder. It was found that there was a problem in that tensile bodies such as chains were buried in the horizontal beams in a slightly loose state, which caused them to flex too much when people got on them, causing them to wobble and become unstable when being lifted and crushed. One way to solve this problem is to make the horizontal bars thicker by thickening the rubber of the horizontal bars, but this requires a large amount of rubber, which increases the cost and makes the horizontal bars thicker. It becomes difficult to understand,
Furthermore, since it becomes difficult to deform, a new problem arises in that the fender function is impaired.

The present invention has been made in order to solve the problems of the prior art, and is to provide a wooden quay wall that does not suffer from permanent deformation due to ship collisions or falling objects, and has good stability because it does not wobble when going up and down. It is an object of the present invention to provide a rubber ladder suitable for use in, etc.

[Means to solve the problem]

The ladder of the present invention that achieves the above object includes a pair of cylindrical rubber side pillars arranged in parallel, and a step having both ends bored in the opposing walls of the pair of side pillars. A plurality of rubber step members are provided which protrude into the internal space of the side column portion through the member hole and have locking portions having a larger diameter than the step portion 4 insertion hole formed at both ends thereof. Each rubber step member is characterized in that a core material is embedded therein, the core material being made of a rigid member near both ends and a flexible member being i'iI in the center.

[For production]

Both ends of each rubber step member are cylindrical rubber. A locking part that protrudes into the internal space of the side column made of aluminum and has a larger diameter than the hole in the stem knob member is formed, and the core material of the step member is made of a flexible member in the center. Therefore, when a load is applied to the step member, the step member and the cylindrical rubber side pillars in contact with the locking portions at both ends undergo WfI deformation, and immediately after the load is removed. It will return to its original shape and no permanent distortion will remain. Further, since both ends of the core material of the step/soop member are made of a rigid member, the step member does not sink much when the ladder is moved up and down, resulting in good stability.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the structure of the step member of the rubber ladder of the present invention, and is an enlarged sectional view of section D in FIG. 3. Also the second
The figure is a plan view of the ladder of the present invention attached to a quay, FIG. 3 is an IE diagram thereof, and FIG. 4 is a partially enlarged view of FIG. 2.

The rubber ladder 1 of the present invention consists of a pair of parallelly arranged rubber side pillars 2.2 and a plurality of step members 3, 3... supported by these side pillars 2.2. It is. Each side pillar portion 2 is formed into a rectangular tube shape and has an internal space 4. As is clear from FIG. 4, a reinforcing iron plate 6 extending in the longitudinal direction is embedded in the rear wall 2a of each side column 2, and a plurality of mounting holes 2b (FIG. 4) are provided at appropriate locations. It is perforated. The rear wall 2a is fixed to the quay wall 8 by passing through these mounting holes 2b, inserting bolts 7 into the quay wall 8, and tightening them with nuts 10. A nut insertion hole 2d is bored in the front wall 2C of the side column portion 2.

A step member insertion hole 2f is formed in each of the opposing side walls 2e, 2e of the pair of side pillars 2.2 at a distance Md from the rear end edge of the side pillar 2.

The rubber step member 3 has both ends 3a. 3a (first
4(a) and 4(b) extend through the step member insertion hole 2f of the side column 2 and protrude into the internal space 4 of the side column 2, and have a diameter larger than that of the step member insertion hole 2f at both ends 3a+3a. A locking portion 3b is formed.

The step member 3 has both ends 3a. A core material 9 in which the vicinity of 3a is made of a rigid member and the central part 3C is made of a flexible member.
is buried. In the illustrated embodiment, the rigid member of the core 9 is a steel pipe 9a and the flexible member is a wire rope 9b extending into a steel pipe 9a and a steel pipe 9a. A part of the made pipe 9a is caulked. FIG. 5(a) is a view taken along the line A-A of the step member where the steel pipe 9a loaded with the wire rope 9b is not caulked, and a view taken along the line B-B of the portion where the steel pipe 9a is caulked. is shown in FIG. 5(b), and FIG. 6 is a view taken along the line C--C of the central portion 3c of the step member 3 in which the wire rope 9b is embedded. In order to make it easier to grasp the step member when going up and down the ladder, as shown in FIG.
A plurality of protrusions 3d, 3d, are provided at appropriate intervals in the circumferential direction.
... is formed in the longitudinal direction.

When a vertical or lateral load is applied to the step member 3 of the ladder 1 configured in this way, the rubber side pillars 2.2
The opposing side walls 2e, 2e are pulled by the step member 3 and deformed so as to be brought to the center, and the step member 3 bends at its center 3c. When the load is removed, the side columns 2, 2
Then, the step member 3 returns to its original state.

[Example of change]

In the above embodiment, the flexible member of the core material 9 of the step member 3 is made of a wire rope, but is not limited to this, and may be a synthetic fiber robe, a chain, or a band-like member having sufficient strength and flexibility. Other members may be used as long as they are appropriate.

Further, the rigid member of the core material 9 is not limited to a steel pipe, but may be of other shapes such as a rod shape or a plate shape. In this case, other fixing methods can be used to fix the flexible member to the rigid member, such as bolting, welding, or pressing with a plate. Further, in the above embodiment, an unevenness for preventing the wire rope 9b from coming off may be provided inside the portion of the steel pipe 9a that is caulked. Further, the shape of the side pillar portion is not limited to the rectangular shape, but may be a cylindrical body having a cross section of another polygon, circular shape, elliptical shape, or the like.

〔Effect of the invention〕

As described above, according to the present invention, both ends of each rubber step member protrude into the internal space of the cylindrical rubber side column, and a locking portion having a larger diameter than the step member insertion hole is formed. In addition, since the step member is made of a flexible member in the center, when a large impact such as a ship collision or falling object is applied to the step member, the step member and its ends will be damaged. The cylindrical rubber side pillars that the stop parts come into contact with are each elastically deformed and immediately return to their original shape after the impact has disappeared, and no permanent deformation remains, so the life of the ladder can be extended. Further, since the core material of the step member is made of a rigid member at both ends, the step member sinks less when the ladder is moved up and down, and therefore has good stability and there is no sense of anxiety when going up and down the ladder.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the structure of the step member of the ladder of the present invention, Fig. 3 is an enlarged cross-sectional view of section D, Fig. 2 is a plan view of the ladder of the invention in a state attached to a quay, and Fig. 3 is the same. Front view, Figure 4 is a partially enlarged view of Figure 2, Figure 5 (a) is the first
5(b) is a view taken along the line B-B in FIG. 1, and FIG. 6 is a view taken along the line C-C in FIG. 1. DESCRIPTION OF SYMBOLS 1... Ladder, 2... Side pillar part, 2f... Step member hole, 3... Step member, 3b... Locking part, 4... Internal space of side pillar, 9...・core material

Claims (2)

[Claims] (1) A pair of cylindrical rubber side pillars arranged in parallel;
Both ends protrude into the internal space of the side pillars through step member insertion holes bored in the opposing walls of the pair of side pillars, and these ends extend beyond the step member insertion holes. A plurality of rubber step members each having a large-diameter locking portion are formed, and each rubber step member has a core member made of a rigid member near both ends and a flexible member in the center. A rubber ladder characterized by being buried. (2) The rigid member is a steel pipe, and the flexible member is a wire rope, each end of the wire rope is extended into the steel pipe, and the steel pipe is caulked. 2. A rubber ladder according to claim 1, characterized in that: