JPH079757Y2 - Large depth screw propeller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a large-depth screw propeller suitable for use in large-depth diving research vessels and unmanned submersibles.

[Conventional technology]

As a conventional screw propeller, there is one as shown in FIG. 2, in which the propeller boss portion 2 is press-fitted into the taper portion 4a at the rear end portion of the propeller shaft 4 driven by a hydraulic motor, an electric motor, etc. The nut 3 is screwed into the male screw portion 4b. The propeller boss 2 and the propeller blade 1 are integrally formed.

The propeller boss portion 2 is fixed to the propeller shaft 4 by a key stop mechanism. That is, the key 5 is press-fitted in a groove cut in the inner circumference of the propeller boss portion 2 and the outer circumference of the tapered portion 4a of the propeller shaft 4, so that the propeller boss portion 2 and the propeller shaft 4 can rotate integrally. Is configured.

The nut 3 abuts on the rear end surface of the propeller boss 2 through the O-ring 8 and the external thread 4 of the propeller shaft 4.
It is screwed to.

The rear end surface of the propeller boss 2 is sealed from outside seawater by an O-ring 8 and the front end surface of the propeller boss 2 is sealed from outside seawater by the backup ring 6 and the U packing 7 '.

Thus, the key groove 9 of the propeller boss 2 and the void 9'in the rear end of the propeller boss 2 have a pressure resistant structure, and are formed by the nut 3 and the male screw portion 4b of the propeller shaft 4. The void 10 'also has a pressure resistant structure.

The reason for sealing the inside of the propeller boss section 2 is to prevent corrosion due to seawater and entry of foreign matter such as dust.

[Problems to be solved by the device]

By the way, if it is a normal surface watercraft, a submersible research ship for shallow depths, and an unmanned underwater vehicle, even if the conventional screw propeller shown in FIG. 2 is used, the keyway 9 and the void 9 ', 1
The 0'withstand voltage structure is very limited, has a large wall thickness, and does not pose a problem in terms of stress.

However, when the depth of use exceeds several thousand meters, the stress generated in the pressure resistant structure cannot be neglected, and some measure is required. As a measure against this,
Two measures can be considered: improvement of material strength and equalization of pressure.

Improvement of material strength is a technology that uses materials with high yield stress such as titanium alloy to withstand the stress when large depth pressure is applied. There are problems such as inviting.

On the other hand, if a conventional large-scale pressure equalizer is installed inside the propeller boss, the screw propeller is a rotating body, so the pressure equalizer is affected by centrifugal force and the shape of the propeller boss becomes large. There is a problem that the propeller water flow is disturbed and the propulsion efficiency is deteriorated.

The present invention is intended to solve such a problem, and by maintaining the shape of the propeller boss part as before, by providing a compact pressure equalizing means in a place where it is hardly affected by centrifugal force. An object of the present invention is to provide a large depth screw propeller capable of preventing deformation of the propeller boss portion due to large depth pressure.

[Means for Solving the Problems]

Therefore, the large-depth screw propeller of the present invention has a propeller boss portion fitted in the rear end portion of the propeller shaft, and abuts the rear end surface of the propeller boss portion through a sealing material and the rear end of the propeller shaft. A nut that is screwed into a male screw portion projecting rearward from the portion, and a key stopper mechanism provided between the inner circumference of the propeller boss portion and the outer circumference of the rear end portion of the propeller shaft. A cap having a bladder for equalizing pressure is mounted on the rear end face in a liquid-tight manner, and a key of the key-locking mechanism is provided from an inner part of the bladder through a screwing part of the nut and the male screw part. A filling liquid filled in a space reaching the groove is provided, and a pressure equalizing hole for guiding the external water pressure to the outer portion of the bladder is formed in the cap to balance the pressure of the filling liquid with the external water pressure. Characterized by There.

[Action]

In the above-described large-depth screw propeller of the present invention, when the external water pressure is guided to the outside of the pressure equalizing bladder through the pressure equalizing hole of the cap, the volume change of the filling liquid due to the external water pressure is absorbed by the deformation of the bladder. As a result, the hydraulic pressure of the filling liquid and the external water pressure are balanced.

That is, the bladder for pressure equalization is formed from a bag that expands and contracts (changes in volume), and dents inward due to an increase in external water pressure to absorb the volume change of the filling liquid due to external water pressure. To work.

〔Example〕

A large-depth screw propeller as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing a main part thereof.

A propeller boss 2 is press-fitted into a tapered portion 4a at the rear end of the propeller shaft 4 driven by a hydraulic motor or an electric motor, and a nut 3 is screwed into a male screw portion 4b of the propeller shaft 4. Then, the propeller boss 2 and the propeller blade 1
And are integrally formed.

The propeller boss 2 and the propeller shaft 4 are fixed by a key stop mechanism. That is, the key 5 is press-fitted in a groove cut in the inner circumference of the propeller boss portion 2 and the outer circumference of the tapered portion 4a of the propeller shaft 4, so that the propeller boss portion 2 and the propeller shaft 4 can rotate integrally. Is configured.

Further, the nut 3 abuts on the rear end surface of the propeller boss portion 2 through the O-ring 8 and at the same time as the male screw portion 4b of the propeller shaft 4.
It is screwed to.

Further, in the embodiment of the present invention, the rubber equalizing bladder 12 is applied to the void portion structurally generated at the rear end portion of the nut 3.
As a result, the pressure of the entire screw propeller is equalized. A bladder is a bag made of rubber that expands and contracts (changes in volume). Such a bag can be used to store hydraulic oil, oil-sealed containers, oil-sealed devices, etc. It is mounted to compensate for volume changes, and is commonly called a "pressure equalizing bladder" because of its use.

That is, a cap 3 ', which is mounted in a liquid-tight manner, is provided on the rear end surface of the nut 3, and these nut 3 and cap 3'are provided.
A rubber pressure equalizing bladder 12 is provided in the cap 3 ', with the peripheral portion sandwiched between and. The connection between the nut 3 and the cap 3'is fixed by a fixing screw 13, and the fixing screw 13 presses the outer peripheral portion of the bladder 12,
It plays the role of preventing oil leakage from the bladder 12.

The key groove 9 of the propeller boss 2 into which the key 5 is fitted and the inner portion 10 of the bladder 12 are communicated with each other by a pressure equalizing groove 11 formed by cutting out a part of the female screw portion of the nut 3. There is.

In this way, the key groove 9 in the key stop mechanism is passed from the inner side portion 10 of the bladder to the pressure equalizing groove 11 in the screwing portion of the nut 3 and the male screw portion 4b and the void portion 9'in the rear end of the propeller boss portion 2. The interior of the space A leading up to is filled with oil as a filling liquid for equalizing pressure, and the cap 3'is equalized so that the depth pressure of seawater is applied to the outer portion of the bladder 12. A hole 14 is formed.

Furthermore, the propeller boss section 2 has a sealing hole for sealing oil.
15 are provided.

The O-ring 8 on the nut 3 side seals oil in the propeller boss 2, and the backup ring 6, O-ring 7, presser plate 6'and fixing screw 6 "at the front end of the propeller boss. Has been.

With the above-described structure, in the embodiment of the present invention, when the deep pressure of seawater is guided to the outer side of the rubber equalizing bladder 12 through the pressure equalizing hole 14 of the cap 3 ', the inside of the propeller boss 2 is filled. The oil receives the seawater pressure through the bladder 12 and has the same hydraulic pressure as the seawater pressure.

That is, the minute volume change of oil due to the depth pressure is absorbed by the pressure equalizing bladder 12, and the oil pressure and the depth pressure of seawater are balanced with each other.

The volume change of the oil due to the depth pressure of several thousand meters is about 5%.

As described above, in the above-described large depth screw propeller of the present invention, since the pressure inside and outside the propeller boss 2 is configured to be balanced, it is possible to use an expensive material having a high yield stress for the propeller boss 2 or the like. Therefore, the propeller boss 2 can be safely used in the deep sea without increasing the thickness of the propeller boss 2.

Moreover, since the pressure equalizing bladder 12 as a pressure equalizing device is compactly provided along the rotation center axis of the screw propeller, the influence of the centrifugal force received by the bladder 12 is small, and the shape of the propeller boss portion 2 is The conventional large-scale pressure equalizing device is built in and the size is not increased, so that the screw propeller is maintained as usual, and the propulsion efficiency of the screw propeller is sufficiently maintained.

[Effect of device]

As described in detail above, according to the large depth screw propeller of the present invention, the following effects and advantages are obtained.

(1) Since the pressure inside and outside the propeller boss is balanced, even when used in the deep sea, the propeller boss does not deform due to the deep pressure, and the meat of the propeller boss etc. Increase the thickness,
There is no need to use expensive materials, resulting in a reduction in material costs.

(2) Since the pressure inside and outside the propeller boss is equalized by a compact means by a bladder provided in the cap, the shape of the propeller boss can be kept small as before, and thus the screw can be maintained. Propeller propulsion efficiency is sufficiently maintained.

(3) Since the pressure equalizing bladder is provided along the rotation center axis of the screw propeller, the influence of the centrifugal force exerted on the pressure equalizing bladder is small, and thus the pressure equalizing device normally operates.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an essential part of a large depth screw propeller as an embodiment of the present invention, and FIG. 2 is a vertical sectional view showing an essential part of a conventional screw propeller. 1 ... propeller blade, 2 ... propeller boss, 3 ...
... nuts, 3 '... caps, 4 ... propeller shafts, 4a ...
… Taper section, 4b …… Male thread section, 5 …… Key, 6 …… Backup ring, 6 ′ …… Presser plate, 6 ″ …… Fixing screw,
7,8 ... O-ring, 7 '... U packing, 9 ... key groove, 9' ... void, 10 ... inside of rubber equalizing bladder 12, 10 '... void, 11 ... … Equalization groove, 12 …… Rubber pressure equalizing bladder, 13 …… Fixing screw, 14 …… Equalization hole, 15 …… Enclosure hole, A …… Space.

Claims (1)

[Scope of utility model registration request] 1. A propeller boss fitted into a rear end of a propeller shaft, and a male screw part that abuts a rear end surface of the propeller boss via a sealing material and projects rearward from the rear end of the propeller shaft. And a key stopper mechanism provided between the inner periphery of the propeller boss portion and the outer periphery of the rear end portion of the propeller shaft, which is liquid-tightly mounted on the rear end surface of the nut. In addition, a cap having a pressure equalizing bladder is provided inside, and the space from the inner part of the bladder to the key groove of the key locking mechanism is passed through the threaded portion between the nut and the male screw portion. A filling liquid is provided, and a pressure equalizing hole for guiding the external water pressure to the outer portion of the bladder is formed in the cap in order to balance the pressure of the filling liquid with the external water pressure. Screw propeller.