JPS60350Y2 - Anti-friction device for impact plates for fenders - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in fenders, and more particularly to means for equalizing the load and impact received by the plastic pads on the surface of the impact plate in a fender with an impact plate.

Comb fenders such as Imada π type and H type are widely used in port facilities, shipbuilding facilities, etc. all over the country.

As schematically shown in Fig. 1, these fenders are commonly equipped with an impact plate (protector) 2 made of a steel plate and an angle on the front side, and a protection plate 2 on the front side of the front plate 2a. is a plastic plate for anti-friction (plastic pad 10 made from a low-friction material such as polyethylene) 3,3...
... are directly fixed to the front plate 2a with bolts and nuts.

However, the outline of the hull that comes into contact with the plastic pads 3 of these fenders is not necessarily an accurate straight line or a simple curve, and may have large and small irregularities due to weld lines, rivets, portholes, drain pipes, various dovetail fittings, etc. Therefore, the hull that comes into contact with this pad will only come into contact with a portion of the pad on the convex portion.

For this reason, excessive friction and pressure are applied to the pad, damaging it, while also easily causing damage such as paint peeling and scratches on the hull side.

In addition, in some cases, the front plate 2, which is a support member of the pad,
Excessive stress is also concentrated on a and the pillars that support it.

Therefore, in reality, as a passive measure, attempts have been made to somewhat weaken the friction by sprinkling water on the sides of ships that are about to berth or have already berthed. There are limits to the amount of water available, and it is especially difficult to reduce friction with the swaying hull of a berthed ship.

The reason why the above problems occur when a ship berths is as follows.
This results in the fact that the contact between the hull and the pad is effectively a point or line contact, and furthermore, the friction between the two is sliding friction.

Among these two causes, for the former, it was considered that the contact with the hull was caused by rolling friction caused by rollers or rotating balls, but since the motion of the hull is a complex trajectory that is a combination of pitching, rolling, and both. Since directional rollers are unsuitable for this purpose, and rotating balls have drawbacks in their supporting means, no examples have been put into practical use.

This invention embodies the concept of maximizing the contact area between the pad and the hull by giving the pad the flexibility to respond to irregularities on the hull, thereby reducing friction between the hull and the pad. This provides an effective solution to the resulting failures.

In order to realize the above concept, the present invention adopts a method in which each unit of the plastic pad is movably attached to the front plate of the impact receiving plate via a rubber elastic body.

Referring to FIG. 2 (side sectional view), which is a typical embodiment of the invention, each plastic pad 3. It is fixed to the front plate 2a with bolts and nuts (6 and 6').

However, since the nut 6' side of the bolt 6 is tightened through the comb washer 5, each plastic pad will adjust to the unevenness of the hull S as the comb elastic butt 4 deforms, as shown by the imaginary line in the figure. 2a.

Because of this, each plastic pad is curved to follow the contours of the hull, so that all pads receive an average load, thus not only protecting themselves from wear, but also protecting the impact plates below them. In addition to preventing damage to the
It also has great effects on ships, such as preventing paint from peeling off and scratches on the ship's hull.

As mentioned above, as a result of preventing the local concentration of stress on the impact plate, the structure of the impact plate itself can be made lighter, and the comb elastic pad 4 also acts as a shock absorber. ,
As a result of these, the performance of the lower fender can be improved, and it can also be downsized, contributing to resource conservation, which are notable examples of indirect effects.

In the above example, the compressive elastic modulus of the rubber elastic pad 4 is 2k to reduce its thickness T1 by about 30%.

It is preferable to use a high compressibility elastomer that requires a force of about /self (=iLl'l'on7i).

However, if the designed contact pressure is smaller, a closed cell foam with an expansion ratio of 2 or less can also be used.

Furthermore, the thickness T2 of the rubber washer on the back of the front plate is pad 3.
It is preferable that the thickness of the pad is equal to or slightly larger than the thickness T□ (that is, T2≧T), and its thickness elastic modulus is also higher than that of the pad 4.

Note that the rubber washer 5 can of course be replaced by a spring washer.

Figure 3 shows an additional embodiment in which a through hole 7 is bored in the center of the plastic pads 3, 3, etc. of the previous example, and the tip of the water nozzle 8 is exposed into the small hole. It is.

As shown in the figure, the wooden nozzle opens perpendicularly to the water pipe 9 fixed to the back side of the upper plate 2a of the impact receiving plate, and its front part passes through the upper plate 2a, the elastic pad 4, and the plastic pad 3. It is located within the hole 7.

In consideration of the displacement of the pad 3, the tip of each nozzle 8 is preferably opened slightly rearward near the boundary between the comb elastic pad 4 and the plastic pad 3.

The end of the water pipe 9 is connected to a high-pressure hose 10 connected to a seawater pump and a strainer (not shown), so that high-pressure seawater can be injected from the tip of the nozzle 8 toward the hull if necessary.

This injection forms a water film on the interface between the hull S and the plastic pad 4, and this water film is maintained stably even if the shape of the interface between the hull S and the pad 4 changes from time to time. The friction between the two becomes even more intense.

Note that if narrow grooves are provided radially from the periphery of the through hole 7 in the center of each unit pad 4 toward the periphery of the pad,
Leakage from the pad surface can be further improved.

As described above, according to the present invention, the contact between the impact-receiving plastic pad and the ship's hull is evened out, thereby overcoming the obstacles when using conventional fixed plastic pads.

What's more, with a built-in water discharge means, which is an additional feature of the invention, the friction-reducing effect of water further reduces friction, completely solving the problem of friction between the hull and the plastic pad, and improving the hull's surface. It is of great value in terms of fender equipment, as it eliminates malfunctions such as peeling of paint, occurrence of scratches, and wear of plastic pads.

[Brief explanation of the drawing]

Figure 1 is a partial side sectional view showing the main parts of a conventional fender with an impact plate, Figure 2 is a sectional view similar to Figure 1 showing the main parts of the proposed anti-friction device, and Figure 3 is the main part of the proposed anti-friction device. FIG. 6 is a side cross-sectional view of an additional embodiment of the device; The meanings of the symbols in the diagram are as follows: 1: Fender, 2: Impact plate, 2a: Front plate, 3 Nibra stick butt, 4: Rubber elastic pad, 5: Rubber washer, 5': Washer , 6: bolt, 6': nut, 7: through hole, 8: nozzle, 9: water pipe, 10: high pressure hose.

Claims (4)

[Scope of utility model registration request] (1) A receiving insert plate characterized in that a protective plastic pad for the impact receiving plate of a fender is movably attached to the front surface of the impact receiving plate via a comb elastic body (rubber pad). anti-friction device. (2) The device according to claim 1, wherein the port for attaching the plastic pad is fixed to the impact plate via a metal washer or a comb washer. (3) The device according to claim (1) or (2), wherein the thickness of the metal washer or the Comb washer is greater than or equal to the thickness of the rubber elastic body (Com pad). (4) The compressive elastic modulus of the metal washer or the Comb washer is higher than that of the Comb elastic body (Com pad), according to any one of registered claims (1) to (3). Device.