HRP970121A2 - Hydraulic and gravity davit - Google Patents

Description

P5 According to the International Convention for the Saving of Life at Sea SOLAS 1974/83 and 92 and IMO Resolution 689, there must be lifeboats on passenger ships that are placed on board according to the exact conditions prescribed and must have devices for lowering and lifting that according to the mentioned regulations produced and tested. According to the latest SOLAS regulations in 1992, lifeboats on passenger ships may no longer be placed on the upper decks of the ship, but in "niches" on the lower decks in order to make the descent of the boat from the boarding deck to the sea as short as possible.

Placing boats in "niches", as well as their devices for lifting and lowering (hereinafter referred to as "soha"), significantly influenced the change in the construction of the soha due to the limited space in width and height.

As far as I know, on passenger ships built so far with boats placed in "niches", soha with several telescopic booms and very expensive hydraulics were used, according to the project of the company SCHAT DAVIT HAMBURG.

My project significantly simplifies and makes soha cheaper, and it can be realized in two versions,

1. Version with hydraulic cylinder called "HYDRAULIC SOHA",

2. Version with the district called "GRAVITATION SOHA".

Description of the invention

1. The regulation dictates that when the ship tilts by ±20° and the ship trims by ±10°, with the condition that the ship is in distress and has no power, the lifeboats must be able to be lowered. hydraulic accumulator, from picture no. 1, it can be seen that the soha is made of the following parts:

The stand 9, which is made of LPG profile a, serves as a guide for the branch 10, which can be pulled in and out. The boom is made of sheet steel of appropriate strength and has a box-shaped section. At the end of the boom, there is a swivel lever 11 (pendulum) over the top of which, with a pulley system, the boat is lowered. The energy accumulated in the form of hydraulic oil under pressure in the hydraulic accumulator 4 is used to eject the boom to the outermost position when the ship tilts at 20°. Activating the control 3 releases the brake of the winch 2, which is carried by the lifeboat via the rope 5. By releasing the brake, the winch 2 relieves the tension of the rope 5 and the hydraulic cylinder 7, which receives oil under pressure from the hydraulic accumulator 4, pushes the boom 10 to the outermost position. The hydraulic accumulator is constantly charged, and a small electro-hydraulic generator is used for charging during normal operation of the ship, and a manual hydraulic pump when the ship is in an accident. In normal operation of the ship, the pendulum 11 is in the closed position "A", and the cylinder 7 brings it to the open position "B", and it can only come when the branch 10 reaches the outermost position. The pendulum is held in the closed position by the lever mechanism 14 (fig. .3 and 4). The boat, against swaying during the navigation of the ship, during normal exploitation, is attached by means of a sea tie 13 in the cradle 12. The winch 2, for raising and lowering the boat, is mounted on the deck 1, from which the crew for handling and steering the boat is loaded into the boat. Passengers board the boat from deck 18 when the crew brings it alongside deck 18. The complete soha are attached by welding to the wall 17 deck 8 and the ship's shell 16.

2. With the Gravitational soha (picture 2), the ejection is achieved by means of the initial impulse created by the force of the spring 5 and then by gravity, because the tilt (base~9) is greater than the prescribed tilt of the ship to the opposite side. The elements of the soha are the base 9, which serves as a guide and is made of an LPG support into which the branch 10 is inserted.

At the end of the branch there is a pivoting lever (pendulum) 11 over the top of which, with a system of pulleys 6 and rope 4 and winch 2, the rescue boat is raised and lowered.

As with the hydraulic soha, activating the control 3 releases the brake of the winch 2, which allows the spring 5 in the initial position, and after gravity, to bring the boom 10 to the outermost position. Spring tensioning is done automatically by winch 2 when retracting the booms 10. is the same as with the hydraulic soha, and in the normal navigation of the ship it is in position "A" and can be released to position "B", only when the boom is extended to the outermost position, using the lever mechanism.

What is significantly different from other saws is the pendulum system, which shortens the extension stroke of the boom by the length "L" (fig. 1 and 2), i.e. by approximately 40% and 30% of the total boom stroke. By shortening the stroke of the branch, the following is achieved:

• Soha has only one branch that can be pulled out (the branch is not from multiple telescopes)

• bending moments are smaller and the read system is also gentler (lighter and cheaper)

• The hydraulic ejection cylinder is shorter and smaller in diameter, which makes it lighter and cheaper

• The hydraulic accumulator is smaller and cheaper

• Shortening the stroke of the branch by the length T gives us the possibility that the entire system with a "niche" of greater height can be performed as a gravity system (with a little help from the spring in the initial moment), so that hydraulics do not need to be used at all.

• By eliminating hydraulics from the extraction system, the entire field becomes cheaper and easier to maintain,

Application

On passenger ships where the height between the decks (alcove height) is small, only hydraulic soha can be installed.

In the case of passenger ships with a higher "niche" height, both hydraulic and gravity soches can be installed.

Claims (5)

1. Hydraulic and gravity hoists, which consist of a base into which the boom is inserted, the boom is retracted using a rope that pulls the winch and is pulled out using a hydraulic system, that is, a spring and gravity, it is indicated by the fact that at the end of the boom there is a pendulum through which the descent is made of the boat, which, in the upper position when the winch is stretched to the end, is locked by a special lever mechanism that opens automatically when the boom is extended to the outermost position, thus allowing the boat to be lowered with a shorter boom ejection length. 2. The hydraulic and gravity boom according to claim 1 and 2 is indicated by the fact that the branch has a rotating pendulum at its outer end that can be locked. 3. Hydraulic and gravity hoist according to claim 1 and 2, characterized by having a lever mechanism that automatically locks the pendulum when the winch retracts the boom to the end and automatically releases it when the boom is extended to the end. 4. The hydraulic boom according to claim No. 1 is indicated by the fact that it has a hydraulic system (hydraulic cylinder and hydraulic accumulator) that pushes the boom to the outermost position and turns the pendulum even when the ship is left without electricity. 5. Gravity area according to request no. 2, is indicated by the fact that it has a spring system that pushes out the boom until it begins to gravitate on its own, so that the boat can be lowered even when there is no electricity on board. energy.