JPH0227003Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dredger, and in particular, in order to enable the elevating motion of the rudder that is lowered to excavate the underwater bottom.
The present invention relates to a dredger that allows maintenance work to be easily and safely performed on the bearing portion of the trunnion shaft that pivotally supports the rudder.

[Prior Art] As shown in FIG. 4, a dredger is equipped with a rudder 1 that is lowered to the bottom of the water to perform dredging work. The rudder 1 is pivoted at its base end 1a via a trunnion shaft 4 rotatably supported by a bearing 3 formed in the hull 2, and is lifted up using the trunnion shaft 4 as a fulcrum to reach the bottom of the water, etc. It is starting to descend.

It is necessary to perform appropriate maintenance work on the bearing portion 3 that rotatably supports the trunnion shaft 4 that pivotally supports the ladder 1 in order to replace parts or the like.

[Problem to be solved by the invention] Conventionally, when maintenance work is performed on the bearing portion 3 of the trunnion shaft 4 that is disposed in a position that is in contact with or immersed in the sea surface L, the weight is extremely large. The large rudder 1 had to be removed from the hull 2. Therefore, since this cannot be done at sea, the rudder 1 must be placed in a dry dock and completely moved using a large crane, or a board may be placed under the rudder 1 to lift the trunnion shaft 4 from the bearing part 3. Ta.

However, it is uneconomical to put the dredger in a dry dock and use large cranes, etc. every time maintenance work is performed, and it is not possible to carry out sufficient and appropriate maintenance work due to the need for docking schedules, etc. There are possible cases.

Further, the work of lifting the trunnion shaft 4 from the bearing portion 3 was dangerous because there was a risk that the heavy ladder would fall.

The present invention was devised in view of the above-mentioned problems, and its purpose is to provide a dredger that can easily and safely perform maintenance work on the bearing part of the trunnion shaft that supports the rudder so that it can be lifted up and down. is to provide.

[Means for Solving the Problems] The present invention provides a dredger having a rudder that is vertically and vertically provided on the hull via a trunnion shaft formed at the base end, which has a V-shaped recess in the hull. Provided is a bearing portion including a bearing seat whose bottom portion is formed in an arc shape, and a bearing cover which is removably attached to a recessed portion of the bearing seat and forms a shaft insertion portion for supporting the trunnion shaft as a bearing; A shaft member is detachably attached to the hull and is provided between the center of gravity of the rudder and the trunnion shaft, and rotatably supports the rudder at a position where the trunnion shaft is rotated upward by the rudder's own weight. .

[Operation] With the above configuration, the bearing part pivots the trunnion shaft between the bearing seat and the bearing cover, thereby raising and lowering the rudder to perform dredging work. During maintenance work, the bearing cover is removed from the bearing seat, the trunnion shaft is removed, and the rudder is swung and deployed by its own weight using the bearing member as a fulcrum, exposing the bearing portion and the trunnion shaft.

[Embodiment] A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, a hull 2 of a dredger is provided with a rudder 1 that is lowered to the bottom of the water and performs dredging. This rudder 1 extends along the longitudinal direction of the hull, and has a tip 1b facing the bottom of the water.
A cutter 5 for excavating earth and sand is provided. On the other hand, the base end 1 located on the hull side of this rudder 1
A trunnion shaft 4 is provided at a. This trunnion shaft 4 is connected to a bearing portion 3 formed in the hull 2.
is rotatably supported. Therefore, Lada 1
is capable of being raised and lowered about the trunnion shaft 4 as a fulcrum.

The bearing part 3 that supports the trunnion shaft 4 here is
As shown in FIG. 2, the bearing seat 6 has a V-shaped recess with an arcuate bottom;
A semi-circular lower bearing piece 7 provided on the arcuate bottom 6a of the bearing seat 6, and a lower bearing piece 7 inserted into the recess of the bearing seat 6.
a bearing cover 9 forming a shaft insertion part 8 with a circular cross section for supporting the trunnion shaft 4 between the bearing cover 9 and a bush 10 disposed around the shaft insertion part 8 formed therein;
It is composed of.

The bearing cover 9 and the bearing seat 6 are detachably bolted to each other at flange portions 9a and 6b formed thereon. Further, the bush 10 is fitted onto the trunnion shaft 4, and the lower bearing piece 7 is fixed to the bush 10. When the trunnion shaft 4 is moved upward, the bush 10 and the lower bearing piece 7 are also removed from the bearing seat 6 together with the shaft 4. Further, the V-shape of the recessed portion of the bearing seat 6 follows the arc-shaped development locus drawn by the upward movement of the trunnion shaft 4, and is designed to guide the movement (the third
(see figure).

On the other hand, as shown in FIG.
A shaft member 11 that pivotally supports the rudder 1 is provided between the trunnion shaft 4 that pivotally supports the rudder 1 and the center of gravity G located in the longitudinal direction of the rudder 1. This shaft member 11 is detachably attached to the hull 2 and inserted into a bracket 12 provided on the rudder 1. This shaft member 11 functions as a rotational fulcrum for the ladder 1 when the bearing cover 9 of the bearing portion 3 is removed from the bearing seat 6. That is, as shown in FIGS. 1 and 3, the trunnion shaft 4 together with the lower bearing piece 7 and the bush 10 is moved upward by the rotational moment generated by the own weight of the rudder 1. ing.

Note that 13 is a cable for controlling the elevating motion of the rudder 1, and is wound around and let out by a winch (not shown).

Next, we will discuss the effect.

When performing maintenance work on the bearing part 3 of the trunnion shaft 4, the position of the rudder 1 is adjusted by the cable 13 as shown in FIG. Insert.

Next, the bearing cover 9 of the bearing part 3 is removed, and then the cables 13 are sequentially loosened.

In this way, the rudder 1 swings and unfolds using the shaft member 11 as a fulcrum due to its own weight, and as a result, as shown in FIG.
0, the trunnion shaft 4 with the lower bearing piece 7 is moved upward onto the ship while drawing an arcuate trajectory, and is sufficiently exposed from the sea surface L.

As described above, in the present invention, a shaft member 11 is provided between the trunnion shaft 4 and the center of gravity G located in the longitudinal direction of the rudder 1 as a rotational fulcrum that rotatably supports the rudder 1 from the hull 2. In addition, since the bearing part 3 is of a split type, the trunnion shaft 4 with the bearing parts such as the bush 10 and the lower bearing piece 7 can be moved upward by the weight of the rudder 1 and positioned on the ship. Moreover, maintenance of bearing parts can be performed safely.

In other words, the dredger can be docked in a dry dock, the rudder moved using a large crane, and the work can be carried out quickly and easily at sea, without the need for dangerous and uneconomical work such as having it supported on boards, etc. obtain.

Further, on the sea, there is no need to position the rudder at a high place, and since the tip portion 1b is submerged in the water and supported by a cable, the rudder can be supported relatively stably, and the work stability is also good.

In particular, the concave part of the bearing seat 6 is formed in a V-shape, and the bearing cover can be attached to and detached from the concave part, so that by moving the trunnion shaft 4 along the concave part, it can be detached or attached very easily and reliably. It is something that can be done.

Incidentally, the shaft member 11 is inserted only during maintenance, and is removed during dredging work, and the rudder 1 is lifted up using the trunnion shaft 4 as a fulcrum.

[Effects of the Invention] In summary, the present invention provides the following excellent effects.

A bearing part having a V-shaped bearing member and a bearing cover is provided on the hull, and a shaft member is provided that rotates the trunnion shaft upward by the weight of the rudder, so the trunnion shaft can be easily removed from the bearing part. It can be detached, and maintenance can be performed on the bearing part economically and safely at sea or elsewhere.

[Brief explanation of the drawing]

Figure 1 is a side view showing one embodiment of the present invention;
The figure is a side sectional view showing the bearing part of the trunnion shaft.
FIG. 4 is a side sectional view of the bearing portion showing a detached state of the trunnion shaft, and FIG. 4 is a side view showing the dredger's rudder in an up-and-down state. In the figure, 1 is a rudder, 2 is a hull, 3 is a bearing part, 4 is a trunnion shaft, 6 is a bearing seat, 8 is a shaft insertion part, 9 is a bearing cover, 11 is a shaft member, and G is the center of gravity of the rudder.

Claims (1)

[Scope of utility model registration request] A dredger having a rudder that is vertically and vertically provided on the hull via a trunnion shaft formed at the base end, wherein the hull includes a bearing seat having a V-shaped recess with an arcuate bottom; A bearing part is provided, the bearing part having a bearing cover that is removably installed in the recessed part of the bearing seat and forms a shaft insertion part for supporting the trunnion shaft as a bearing, and the bearing part is removably installed in the hull and is attached to the rudder. A dredger comprising a shaft member between a center of gravity and the trunnion shaft that rotatably supports the rudder at a position where the trunnion shaft is rotated upward by the own weight of the rudder.