JPH0426504Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> This invention is mainly for fenders that are installed on quay walls and are made of rubber-like elastic material and have a roughly V-shaped cross section and are formed to an appropriate length. Regarding improvements.

<Prior Art> The basic structure of this type of fender, as shown in FIG. 3, consists of an impact receiving part 1, supporting parts 2, 2, and attachment parts 3, 3. Fender 4 with such a configuration
In general, the reaction force-strain curve when a load is applied to the impact receiving part 1 is as shown by curve A in FIG. 4. That is, the curve A has a portion A ₁ that rises at a steep slope, a portion A ₂ that is flat, and a portion A ₃ that rises again at a steep slope. For such fenders, the range of portions A ₁ and A ₂ of curve A is utilized.

Although the shape shown in FIG. 3 is the basic shape, there are many proposals for improving energy absorption performance, etc. For example, Japanese Patent Publication No. 56-9604,
These include Publication No. 58-153218, Publication of Japanese Utility Model Application No. 60-70629, and Japanese Patent Application Publication No. 189403/1983. However, in both cases, the reaction force-strain curves tend to be similar to those shown in FIG.

<Problems to be solved by the invention> Conventional fenders have a high initial reaction force, as shown by curve A in Figure 4, so if they are manufactured for large ships, they will not be suitable for small ships. There is a problem that the impact is large when docking and can damage small ships, and if it is manufactured for small ships, it cannot be used for large ships.

In addition, if the impact receiving part is not made of a special material but is made of the same rubber as the supporting part, if the compression ratio in the height direction of the fender reaches approximately 30% or more, the upper surface of the impact receiving part The middle part in the width direction is depressed. For this reason, the contact area with the ship's side becomes smaller, and the reaction force per unit area becomes larger, so in the case of large ships, the outer skin is often weak and there is a risk of damage. Furthermore, in this type of ship, the normally square upper surface (side contact surface) of the support part is flat, and the entire surface of the support part comes into contact with the ship during coming alongside, making it difficult to slip. There is also a problem in which damage occurs from 1a) and leads to breakage.

This invention aims to provide a fender that solves the above problems.

<Means for solving the problem> The means of this invention consists of an impact receiving part having a predetermined width and an appropriate length, and a space on the back of the impact receiving part that protrudes rearward from both sides, and the distance is larger than the front end. A fender comprising: a sidewall-like support section extending so as to be wider at the rear end; and a sidewall-like support section formed integrally with a rubber-like elastic material, and a flange-like attachment section provided at each rear end of the support section. In this case, a cross-sectional shape perpendicular to the length direction of the front surface of the impact-receiving portion includes an arcuate line forming a protrusion projecting forward at the center and first arcuate lines extending outwardly on both sides of the arcuate line. It is characterized by having a deformation line consisting of a straight line and a second straight line following the outer end of the first straight line and extending rearward on both sides substantially parallel to each other and continuing to the outer surface of the front end of the support part. shall be.

<Operation> According to this means, since there is a protrusion extending along the length in the widthwise center of the front surface of the impact receiving part, when it comes into contact with the side, the front end of the protrusion hits first and is pressed by the side. and transforms as follows. The convex portion is an arcuate line portion in the cross-sectional shape, and the arcuate line portion becomes a straight line that coincides with the gunwale at the contact portion with the gunwale, and the linear area gradually increases and the arcuate line area decreases. During this time, the supporting portion is also slightly compressed and deformed, and the impact receiving portion as a whole is bent in such a manner that the beams supported at both ends receive a concentrated load at the center. Therefore, in the process of reducing the arcuate line area, the first straight line comes into contact with the gunwale from the outer end, and the contact area gradually expands until most of the front surface of the impact area comes into contact with the gunwale. Once this happens, the deformation of the impact receiving part will settle down. After that, the compression of the struts gradually progresses, and the struts begin to curve outward in the middle of the fore-and-aft direction, and the degree of this gradually increases. It increases in size, and a part of the outer surface of both supports comes into contact with the gunwale.

The reaction force of the deformation process described above is caused by adding a rising part with a gentle slope to the bottom of part _A1 of curve A shown in Figure 4 on the reaction force-strain curve, and the whole is translated to the right by that amount. The state will be as follows. That is, at the initial stage of deformation, there is a portion where the deformation is large relative to the reaction force.

<Example> A first example is shown in FIGS. 1a and 1b. In the figure, 10 is an impact receiving part, 11, 11 is a supporting part, 12,
Reference numeral 12 denotes a mounting portion, which is formed to have a uniform cross-sectional shape and a predetermined length, and is integrally formed of rubber as a whole.

The impact receiving portion 10 is formed in a substantially plate shape, and has a convex portion 13 on the front surface, which is the side on the side in use. The convex portion 13 protrudes as shown by an arcuate line 13a in FIG. 1a. Continuing on both sides of the arcuate line 13a, first straight lines 10a, 10a extend outward and backward, respectively.
The second straight lines 10b, 10b extend in a 90 degree bent form to form the front surface of the impact receiving portion 10. A recess 14 is formed on the back surface of the impact receiving part 10 in correspondence with the convex part 13.

The support parts 11, 11 are formed in the form of side walls extending rearward from both outer sides of the back surface of the impact receiving part 10, and extend rearward at a predetermined angle therebetween.

The attachment portions 12, 12 are formed in a flange shape, expanding from the rear ends of the support portions 11, 11 to both sides. Although not shown, bolt holes for attachment to the quay are provided in the attachment parts 12, 12.

As shown in FIG. 1a, this fender 15 has a height (length in the longitudinal direction) of H, a protrusion amount of the convex part 13 of h, a width of the impact receiving part 10 of _W1 , and a width of the convex part 13. Assuming that W ₂ is h=0.1H, W ₂ =0.45W ₁ . In addition,
The thickness of each of the impact receiving part 10 and the supporting part 11 is approximately _0.2W1 .

The reaction force-strain curve of the fender 15 is as shown by B in FIG. 4, and has a rising portion _B1 with a gentle slope at the initial stage of deformation.

Due to the existence of this part _B1 , this fender 15
can accommodate small ships.

According to experiments related to the first embodiment, the convex portion 13
If the protrusion amount h is small, the distance between point 0 and point a on the curve B becomes small, and the fender performance for small ships deteriorates. In other words, it approaches curve A. If the amount of protrusion of the convex portion 13 is large, the curve B rises quickly after point C, and the energy absorption performance deteriorates. In addition, when the width W ₂ of the convex part 13 is small, when a deformation state that produces a large reaction force is reached, that is, after the point b of the curve B, the contact area between the convex part 13 and the gunwale decreases, and both sides thereof A considerably large gap is created in the ship, the contact area between the impact receiving part 10 and the ship side becomes small, and the reaction force per unit area increases. If the width W ₂ of the convex portion 13 is too large, the initial reaction force will be large, making it impossible to accommodate small ships. For this reason, the height h of the protrusion 13 is 0.03H to 0.3H, and the width W ₂ of the protrusion 13 is 0.3W ₁
It is desirable to be within the range of ~0.8W ₁ .

In the first embodiment, the recess 14 is provided on the back surface of the impact receiving part 10, but when compared with the fender 15a shown in FIG. Although the rising slope between 0 and a is somewhat steep, it is sufficient to accommodate small ships, so the concavity 14
shall be provided as necessary.

<Effects of the invention> According to this invention, by providing a convex portion on the front surface of the impact receiving part, contact is made at the convex part in the initial stage of coming alongside, so the corners on both sides of the impact receiving part, which were conventionally damaged, are reduced. No more damage. In addition, the reaction force-strain curve has a gentle slope part at the initial stage of deformation, and then becomes almost the same curve as the conventional one during the subsequent deformation process. Hot spots are removed. Furthermore, in the case of conventional fenders of this type where the entire impact receiving part is made of rubber, as the entire deformation progresses, depressions are formed on the impact receiving surface and this increases, resulting in an increase in the contact surface pressure. The problem is solved by providing the protrusion.

[Brief explanation of drawings]

FIG. 1 shows a first embodiment of this invention, a is a front view, b is a plan view, and FIG. 2 is a front view of another embodiment.
FIG. 3 is a perspective view of a conventional fender, and FIG. 4 is a graph showing a reaction force-strain curve showing the characteristics of the fender. DESCRIPTION OF SYMBOLS 10... Impact receiving part, 11... Supporting part, 12... Mounting part, 13... Convex part, 10a... First straight line, 1
0b...Second straight line.

Claims (1)

[Scope of utility model registration request] A receiving portion having a predetermined width and an appropriate length, and a side wall-like supporting portion extending rearward from both sides at a distance from the back of the receiving portion so that the distance is wider at the rear end than at the front end. and a fender integrally formed of a rubber-like elastic material and each having a flange-like attachment part at the rear end of the support part, at right angles to the length direction of the front part of the impact receiving part. The cross-sectional shape is an arcuate line forming a convex portion protruding forward at the center, a first straight line extending outwardly on each side of the arcuate line, and an outer end of the first straight line continuing backwardly on both sides. and a second straight line extending substantially parallel to each other and continuing to the outer surface of the front end of the support section.