SELF-BALANCED PRESSURE HULL DEVICE

Abstract

A self-balanced pressure hull device, belonging to the field of pressure structure technology of deep-sea submersibles, being assembled by nesting, from inside to outside, a spherical inner housing, a spherical intermediate housing and a spherical outer housing around the sphere centre, pairs of symmetric coaxial connecting shaft components being connected between the spherical inner housing and the spherical intermediate housing and between the spherical intermediate housing and the spherical outer housing, respectively; axes of the two pairs of connecting shaft components are perpendicular to each other so as to enable the spherical inner housing and the spherical intermediate housing to rotate relative to each other, and the spherical intermediate housing and the spherical outer housing to rotate relative to each other; and each of the connecting shaft components in the two pairs being provided with a spring damper for resisting the axial impact between each two adjacent housings.

Claims

1. A self-balanced pressure hull device, wherein assembled by successively nesting, from inside to outside, a spherical inner housing, a spherical intermediate housing and a spherical outer housing around the sphere centre, pairs of symmetric coaxial connecting shaft assemblies being connected between the spherical inner housing and the spherical intermediate housing and between the spherical intermediate housing and the spherical outer housing, respectively; axes of the two pairs of connecting shaft assemblies being perpendicular to each other so as to enable the spherical inner housing and the spherical intermediate housing to rotate relative to each other, and the spherical intermediate housing and the spherical outer housing to rotate relative to each other; and each of the connecting shaft assemblies in the two pairs being provided with a spring damper for resisting an axial impact between each two adjacent housings, wherein the spherical inner housing is formed by connecting a hemispherical inner housing I and a hemispherical inner housing II, the spherical intermediate housing is fondled by connecting a hemispherical intermediate housing I and a hemispherical intermediate housing II, and the spherical outer housing is formed by connecting a hemispherical outer housing I and a hemispherical outer housing II; pairs of symmetric limiting buffers are provided between the spherical inner housing and the spherical intermediate housing and between the spherical intermediate housing and the spherical outer housing, respectively; a connecting line of the limiting buffers between the spherical inner housing and the spherical intermediate housing is perpendicular to an axis of connecting shaft assemblies between the spherical inner housing and the spherical intermediate housing; and a connecting line of the limiting buffers between the spherical intermediate housing and the spherical outer housing is perpendicular to a connecting axis of the intermediate inner housing and the spherical outer housing; the spherical inner housing is provided with an inner compartment hatch, the spherical intermediate housing is provided with an intermediate compartment hatch, and the spherical outer housing is provided with an outer compartment hatch, the inner compartment hatch, the intermediate compartment hatch, and the outer compartment hatch being each disposed with a circular hatch cover; an inner hatch cover is connected to an inner wall of the inner housing via an inner hatch cover connecting pin-shaft assembly, tightly pressed by an inner hatch cover press plate mounted on the inner wall of the inner housing, and sealed by an O-shaped seal ring; an intermediate hatch cover is connected to an outer wall of the inner housing via an intermediate hatch cover connecting pin-shaft assembly, tightly pressed by an intermediate hatch cover press plate mounted on an outer wall of the intermediate housing, and sealed by an O-shaped seal ring; and an outer hatch cover is connected to an outer wall of the outer housing via an outer hatch cover connecting pin-shaft assembly, tightly pressed by an outer hatch cover press plate mounted on the outer wall of the outer housing, and sealed by an O-shaped seal ring; and an inner hatch cover hose connector is connected to an outer hatch cover hose connector via an inner compartment hose and connector assembly to connect an inner compartment inside the spherical inner housing with an external auxiliary submersible, so as to maintain a standard air pressure in the inner compartment inside the spherical inner housing; an intermediate hatch cover hose connector is connected to the outer hatch cover hose connector via an intermediate compartment hose and connector assembly to connect an intermediate compartment between the spherical inner housing and the spherical intermediate housing with the external auxiliary submersible, so as to maintain a vacuum in the intermediate compartment between the spherical inner housing and the spherical intermediate housing; and an outer compartment between the intermediate housing and the outer housing is connected to the external auxiliary submersible via the outer hatch cover hose connector, so as to maintain an air pressure in the outer compartment between the intermediate housing and the outer housing at a half of a hydraulic pressure outside the submersible at its working depth, the outer hatch cover hose connector being a three-tier metal connector in a nesting mode, with inner, middle, and outer tiers being respectively connected to the inner, intermediate, and outer compartments via metal hoses; and the inner hatch cover hose connector, the intermediate hatch cover hose connector and the outer hatch cover hose connector being respectively connected to the inner hatch cover, the intermediate hatch cover and the outer hatch cover through threads and sealed by O-shaped seal rings.

2. The self-balanced pressure hull device according to claim 1, wherein the two connecting shaft assemblies between the spherical intermediate housing and the spherical outer housing are of the same structure and size, and each connecting shaft assembly comprises a spring damper, a pedestal, a connecting shaft, a slide bearing, an inner bearing bush, an outer bearing bush, a bearing press plate, and a screw, the slide bearing being fixed on the connecting shaft via the bearing press plate and the screw; the inner bearing bush being disposed between an inner wall of the slide bearing and the connecting shaft; the connecting shaft being supported on the outer wall of the spherical intermediate housing; the pedestal being supported on the inner wall of the spherical outer housing; the outer bearing bush being disposed between an outer wall of the slide bearing and the pedestal; and the spring damper being mounted on an outer side of the pedestal (152,162), with two ends being tightly pressed against the connecting shaft and a protrusion of the pedestal respectively; and the two connecting shaft assemblies between the spherical inner housing and the spherical intermediate housing are of the same structure and size, and each connecting shaft assembly comprises a spring damper, a pedestal, a connecting shaft, a slide bearing, an inner bearing bush, an outer bearing bush, a bearing press plate, and a screw, the slide bearing being fixed on the connecting shaft via the bearing press plate and the screw; the inner bearing bush being disposed between an inner wall of the slide bearing and the connecting shaft; the connecting shaft being supported on the outer wall of the spherical inner housing; the pedestal being supported on the inner wall of the spherical intermediate housing; the outer bearing bush being disposed between an outer wall of the slide bearing and the pedestal; and the spring damper being mounted on an outer side of the pedestal, with two ends being tightly pressed against the connecting shaft and a protrusion of the pedestal respectively.

3. The self-balanced pressure hull device according to claim 1, wherein the two limiting buffers between the spherical inner housing and the spherical intermediate housing are of the same structure and size, and each limiting buffer comprises an upper support plate, a middle support plate, a lower support plate, an upper hydraulic damper, and a lower hydraulic damper, the middle support plate being welded to the outer wall of the spherical inner housing; the upper support plate and the lower support plate being respectively disposed on a lower support plate upper pedestal and a lower support plate lower pedestal which are connected to the inner wall of the spherical intermediate housing; the upper hydraulic damper and the lower hydraulic damper being symmetrically arranged about the middle support plate; one end of each of the upper hydraulic damper and the lower hydraulic damper being connected to the middle support plate via a universal joint; the other end of the upper hydraulic damper being connected to the upper support plate via a universal joint; and the other end of the lower hydraulic damper being connected to the lower support plate via a universal joint; and the two limiting buffers between the spherical intermediate housing and the spherical outer housing are of the same structure and size, and each limiting buffer comprises an upper support plate, a middle support plate, a lower support plate, an upper hydraulic damper, and a lower hydraulic damper, the middle support plate being welded to the outer wall of the spherical inner housing; the upper support plate and the lower support plate being respectively disposed on a lower support plate upper pedestal and a lower support plate lower pedestal which are connected to the inner wall of the spherical intermediate housing; the upper hydraulic damper and the lower hydraulic damper being symmetrically arranged about the middle support plate; one end of each of the upper hydraulic damper and the lower hydraulic damper being connected to the middle support plate via a universal joint; the other end of the upper hydraulic damper being connected to the upper support plate via a universal joint; and the other end of the lower hydraulic damper being connected to the lower support plate via a universal joint.

4. The self-balanced pressure hull device according to claim 1, wherein the inner hatch cover press plate is connected to the inner housing via a mandrel assembly and tightly pressed by a screw assembly; the intermediate hatch cover press plate is connected to the intermediate housing via a mandrel assembly and tightly pressed by a screw assembly; and the outer hatch cover press plate is connected to the outer housing via a mandrel assembly and tightly pressed by a screw assembly.

5. The self-balanced pressure hull device according to claim 1, wherein diameters D.sub.1, D.sub.2, and D.sub.3 of the spherical inner housing, the spherical intermediate housing and the spherical outer housing meet the following proportional relationship: 2:3:4, the diameter of the spherical inner housing ranging from 2.2 m to 3.1 m.

6. The self-balanced pressure hull device according to claim 5, wherein diameters L.sub.1, L.sub.2, and L.sub.3 of the inner compartment hatch, the intermediate compartment hatch and the outer compartment hatch meet the following proportional relationship: 1:1:2, the diameter of the inner compartment hatch ranging from 0.7 m to 1.1 m.

7. The self-balanced pressure hull device according to claim 3, wherein the lower support plate upper pedestal and the lower support plate lower pedestal are two symmetric semi-pedestals, the two semi-pedestals being welded to rims of corresponding hemispherical housings respectively; and after the two hemispherical housings are assembled into a complete spherical housing, the upper support plate and the lower support plate are clamped in the two corresponding semi-pedestals respectively.

8. The self-balanced pressure hull device according to claim 1, wherein a counterweight is placed on each of the bottoms of the spherical inner housing, the spherical intermediate housing and the spherical outer housing.

9. The self-balanced pressure hull device according to claim 2, wherein the slide bearing is an integral self-lubricating bearing.

10. The self-balanced pressure hull device according to claim 2, wherein the spring damper is replaced with a rubber damper.

11. The self-balanced pressure hull device according to claim 2, wherein the inner hatch cover press plate is connected to the inner housing via a mandrel assembly and tightly pressed by a screw assembly; the intermediate hatch cover press plate is connected to the intermediate housing via a mandrel assembly and tightly pressed by a screw assembly; and the outer hatch cover press plate is connected to the outer housing via a mandrel assembly and tightly pressed by a screw assembly.

12. The self-balanced pressure hull device according to claim 3, wherein the inner hatch cover press plate is connected to the inner housing via a mandrel assembly and tightly pressed by a screw assembly; the intermediate hatch cover press plate is connected to the intermediate housing via a mandrel assembly and tightly pressed by a screw assembly; and the outer hatch cover press plate is connected to the outer housing via a mandrel assembly and tightly pressed by a screw assembly.

13. The self-balanced pressure hull device according to claim 2, wherein diameters D.sub.1, D.sub.2, and D.sub.3 of the spherical inner housing, the spherical intermediate housing and the spherical outer housing meet the following proportional relationship: 2:3:4, the diameter of the spherical inner housing ranging from 2.2 m to 3.1 m.

14. The self-balanced pressure hull device according to claim 13, wherein diameters L.sub.1, L.sub.2, and L.sub.3 of the inner compartment hatch, the intermediate compartment hatch and the outer compartment hatch meet the following proportional relationship: 1:1:2, the diameter of the inner compartment hatch ranging from 0.7 m to 1.1 m.

15. The self-balanced pressure hull device according to claim 3, wherein diameters D.sub.1, D.sub.2, and D.sub.3 of the spherical inner housing, the spherical intermediate housing and the spherical outer housing meet the following proportional relationship: 2:3:4, the diameter of the spherical inner housing ranging from 2.2 m to 3.1 m.

16. The self-balanced pressure hull device according to claim 15, wherein diameters L.sub.1, L.sub.2, and L.sub.3 of the inner compartment hatch, the intermediate compartment hatch and the outer compartment hatch meet the following proportional relationship: 1:1:2, the diameter of the inner compartment hatch ranging from 0.7 m to 1.1 m.

17. The self-balanced pressure hull device according to claim 2, wherein a counterweight is placed on each of the bottoms of the spherical inner housing, the spherical intermediate housing and the spherical outer housing.

18. The self-balanced pressure hull device according to claim 3, wherein a counterweight is placed on each of the bottoms of the spherical inner housing, the spherical intermediate housing and the spherical outer housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a front view of a complete section of a completely assembled self-balanced pressure hull device;

[0027] FIG. 2 is a left view of a complete section of a completely assembled self-balanced pressure hull device;

[0028] FIG. 3 is a top view of a complete section of a completely assembled self-balanced pressure hull device;

[0029] FIG. 4 is a partial enlarged sectional view of an outer hatch cover press plate assembly 7 and an outer hatch cover sealing member;

[0030] FIG. 5 is a partial enlarged sectional view of an intermediate hatch cover press plate assembly 8 and an intermediate hatch cover sealing member;

[0031] FIG. 6 is a partial enlarged sectional view of an inner hatch cover press plate assembly 9 and an inner hatch cover sealing member;

[0032] FIG. 7 is a partial enlarged sectional view of a three-tier nesting-mode outer hatch cover hose connector assembly 12 and a metal hose connector;

[0033] FIG. 8 is a partial enlarged sectional view of an intermediate hatch cover hose connector assembly 11 and a metal hose connector;

[0034] FIG. 9 is a partial enlarged sectional view of an inner hatch cover hose connector assembly 10 and a metal hose connector;

[0035] FIG. 10 is a partial enlarged sectional view of a connecting shaft assembly 15 between an inner housing and an intermediate housing;

[0036] FIG. 11 is a partial enlarged sectional view of a connecting shaft assembly 16 between an inner housing and an intermediate housing;

[0037] FIG. 12 is a partial enlarged sectional view of a connecting shaft assembly 17 between an intermediate housing and an outer housing;

[0038] FIG. 13 is a partial enlarged sectional view of a connecting shaft assembly 18 between an intermediate housing and an outer housing;

[0039] FIG. 14 is a partial bottom view of an inner hatch cover assembly 21 and an inner hatch cover press plate assembly 9;

[0040] FIG. 15 is a partial top view of an intermediate hatch cover assembly 20 and an intermediate hatch cover press plate assembly 8;

[0041] FIG. 16 is a partial top view of an outer hatch cover assembly 19 and an outer hatch cover press plate assembly 7;

[0042] FIG. 17 is a partial enlarged sectional view of a rotary buffering and limiting assembly 22 between an inner housing and an intermediate housing;

[0043] FIG. 18 is a partial enlarged sectional view of a rotary buffering and limiting assembly 23 between an inner housing and an intermediate housing;

[0044] FIG. 19 is a partial enlarged sectional view of a rotary buffering and limiting assembly 24 between an intermediate housing and an outer housing; and

[0045] FIG. 20 is a partial enlarged sectional view of a rotary buffering and limiting assembly 25 between an intermediate housing and an outer housing.

[0046] In the drawings: 1inner housing I, 2inner housing II, 3intermediate housing I, 4intermediate housing II, 5outer housing I, 6outer housing II, 7outer hatch cover press plate assembly, 71outer hatch cover press plate screw, 72outer hatch cover press plate, 73mandrel of the outer hatch cover, 8intermediate hatch cover press plate assembly, 81mandrel of the intermediate hatch cover, 82intermediate hatch cover press plate, 83intermediate hatch cover screw, 9inner hatch cover press plate assembly, 91mandrel of the inner hatch cover, 92inner hatch cover screw, 93inner hatch cover press plate, 10inner hatch cover hose connector assembly, 101inner hatch cover hose connector, 102inner hatch cover hose connector seal ring, 11intermediate hatch cover hose connector assembly, 111intermediate hatch cover hose connector, 112intermediate hatch cover hose connector seal ring, 12outer hatch cover hose connector assembly, 121outer hatch cover hose connector, 122outer hatch cover hose connector seal ring, 13intermediate compartment hose and connector assembly, 131intermediate compartment hose nut I, 132intermediate compartment hose seal ring I, 133intermediate compartment hose sealing bush I, 134intermediate compartment hose, 135intermediate compartment hose sealing bush II, 136intermediate compartment hose seal ring II, 137intermediate compartment hose nut II, 14inner compartment hose and connector assembly, 141inner compartment hose nut I, 142inner compartment hose seal ring I, 143inner compartment hose sealing bush I, 144inner compartment hose, 145inner compartment hose sealing bush II, 146inner compartment hose seal ring II, 147inner compartment hose nut II, 15connecting shaft assembly I between the intermediate housing and the outer housing, 151spring damper, 152pedestal, 153connecting shaft, 154bearing press plate, 155screw, 156inner bearing bush, 157slide bearing, 158outer bearing bush, 16connecting shaft assembly II between the intermediate housing and the outer housing, 161spring damper, 162pedestal, 163connecting shaft, 164bearing press plate, 165screw, 166bearing bush, 167slide bearing, 168bearing bush, 17connecting shaft assembly I between the inner housing and the intermediate housing, 171spring damper, 172pedestal, 173connecting shaft, 174bearing press plate, 175screw, 176inner bearing bush, 177slide bearing, 178outer bearing bush, 18connecting shaft assembly II between the inner housing and the intermediate housing, 181spring, 182pedestal, 183connecting shaft, 184bearing press plate, 185screw, 186inner bearing bush, 187slide bearing, 188outer bearing bush, 19outer hatch cover assembly, 191inner hatch cover seal ring, 192inner hatch cover, 193outer hatch cover connecting pin and shaft, 20intermediate hatch cover assembly, 201intermediate hatch cover seal ring, 202intermediate hatch cover, 203intermediate hatch cover connecting pin and shaft, 21inner hatch cover assembly, 211inner hatch cover seal ring, 212inner hatch cover, 213inner hatch cover connecting pin and shaft, 22rotary limiting buffer I between the inner housing and the intermediate housing, 221upper support plate, 222universal joint, 223upper hydraulic damper, 224universal joint, 225middle support plate, 226universal joint, 227lower hydraulic damper, 228universal joint, 229lower support plate, 2210lower support plate upper pedestal, 2211lower support plate lower pedestal, 23rotary limiting buffer II between the inner housing and the intermediate housing, 231upper support plate, 232universal joint, 233upper hydraulic damper, 234universal joint, 235middle support plate, 236universal joint, 237lower hydraulic damper, 238universal joint, 239lower support plate, 24rotary limiting buffer I between the intermediate housing and the outer housing, 241upper support plate, 242universal joint, 243upper hydraulic damper, 244universal joint, 245middle support plate, 246universal joint, 247lower hydraulic damper, 248universal joint, 249lower support plate, 2410lower support plate upper pedestal, 2411lower support plate lower pedestal, 25rotary limiting buffer II between the intermediate housing and the outer housing, 251upper support plate, 252universal joint, 253upper hydraulic damper, 254universal joint, 255middle support plate, 256universal joint, 257lower hydraulic damper, 258universal joint, 259lower support plate, 26counterweight on the inner housing, 27counterweight on the intermediate housing, and 28counterweight on the outer housing.

DESCRIPTION OF THE EMBODIMENTS

[0047] The working principle, connection, and assembly of a self-balanced pressure hull device of the present invention is described in detail below with reference to FIG. 1 to FIG. 15 of the patent.

[0048] As shown in FIG. 2 to FIG. 9, the present invention is assembled by successively nesting, from inside to outside, a spherical inner housing, a spherical intermediate housing and a spherical outer housing around the sphere centre. The spherical inner housing and the spherical intermediate housing, as well as the spherical intermediate housing and the spherical outer housing, are axially connected via a pair of slide bearings. Two axes are mutually perpendicular, such that the spherical inner housing and the spherical intermediate housing, as well as the spherical intermediate housing and the spherical outer housing, can rotate relative to each other. Each of the connecting shafts in the two pairs is provided with a spring damper at the outside, for resisting an axial impact between each two adjacent housings. The spherical inner housing is formed by connecting a hemispherical inner housing I 1 and a hemispherical inner housing II 2, the spherical intermediate housing is formed by connecting a hemispherical intermediate housing I 3 and a hemispherical intermediate housing II 4, and the spherical outer housing is formed by connecting a hemispherical outer housing I 5 and a hemispherical outer housing II 6.

[0049] FIG. 10 and FIG. 11 show a pair of shaft components connecting the intermediate housing and the outer housing. Because their structures and sizes are totally identical, they are described by using FIG. 9 as an example. The connecting shaft assembly between the intermediate housing and the outer housing includes a spring damper, a slide bearing pedestal, a connecting shaft, a slide bearing, bearing bushes, a bearing press plate, and a screw. The slide bearing uses an integral self-lubricating bearing, and lubricating grease is smeared in the first assembly.

[0050] The slide bearing is fixed on an outer compartment shaft 153 via a press plate 154 and a screw 155, and is supported by an outer compartment shaft pedestal 152. The spring damper 151 is mounted on an outer side of the pedestal 152, with two ends being tightly pressed against a protrusion. FIG. 12 and FIG. 13 show a pair of shaft components connecting the inner housing and the intermediate housing. Because their structures and sizes are totally identical, they are introduced by using FIG. 11 as an example. The connecting shaft assembly between the inner housing and the intermediate housing includes a spring damper, a slide bearing pedestal, a connecting shaft, a slide bearing, bearing bushes, a bearing press plate, and a screw. The slide bearing is fixed on an intermediate compartment shaft 173 via a press plate 174 and a screw 175, and is supported by an intermediate compartment shaft pedestal 172. The spring damper 171 is mounted on an outer side of the pedestal 172, with two ends being tightly pressed against a protrusion. The connecting shafts and the pedestals are welded to corresponding housings.

[0051] In order to ensure that the three compartment doors face upwards in the same directions under the balanced state of the housings, and to maintain a correct posture of the whole submersible, the following two measures are adopted: First, a counterweight is placed on each of the bottoms of the housings (as shown in FIG. 1), and the center of gravity is lowered. Secondly, two ends of the spring damper is connected to a corresponding housing or a rubber damper is used instead.

[0052] During actual operation of the submersible, in order to prevent connecting pipelines and other accessories from being damaged due to relative rotation between the three housings, it is required to limit relative rotation between each adjacent housings, and it is stipulated that an absolute value of a rotation angle between the adjacent housings is not greater than 15. Moreover, it is required to buffer relative rotation between each adjacent housings. FIG. 17 and FIG. 18 each show a rotary limiting buffer between the inner housing and the intermediate housing, and FIG. 19 and FIG. 20 each show a rotary limiting buffer between the intermediate housing and the outer housing. Because the limiting buffers are of the identical structures, they are described by using FIG. 17 as an example. The whole limiting buffer includes upper, middle, and lower support plates and corresponding pedestals, two symmetrically disposed hydraulic dampers, and four universal joints for connecting the hydraulic dampers and the support plates. A connecting line of the limiting buffers between the inner housing and the intermediate housing is perpendicular to a connecting axis thereof, and a connecting line of the limiting buffers between the intermediate housing and the outer housing is perpendicular to a connecting axis thereof. When the submersible is at a stable and balanced state, the two pairs of housing connecting shafts and limiting buffers are on the same horizontal plane. The middle support plates are welded to the housings, and the universal joints are welded to corresponding support plates. The upper and the lower support plate pedestals of the hydraulic damper are two symmetric semi-pedestals. The two semi-pedestals are welded to rims of corresponding hemispherical housings respectively. After the two hemispherical housings are assembled into a complete spherical housing, the upper support plate and the lower support plate of the hydraulic damper are clamped in the two corresponding semi-pedestals respectively.

[0053] To ensure sufficient space between each adjacent housings, it is stipulated that diameters D.sub.1, D.sub.2, and D.sub.3 of the inner housing, the intermediate housing and the outer housing meet the following proportional relationship: 2:3:4, the diameter of the inner housing ranging from 2.2 m to 3.1 m. Withstanding a high pressure, the intermediate housing and the outer housing need to use a high-strength alloy material. The titanium alloy is recommended, where thicknesses h.sub.2 and h.sub.3 are calculated according to the design depth of the submersible. Withstanding a low pressure, the inner housing may use common low-carbon alloy steel, where the thickness h.sub.1 is calculated according to the permissible stress of the material and a withstood air pressure.

[0054] As shown in FIG. 1, an inner compartment hatch, an intermediate compartment hatch, and an outer compartment hatch are successively disposed from the bottom up. The three compartment hatches are each provided with a circular hatch cover (as shown in FIG. 13, FIG. 14, and FIG. 15). An inner hatch cover 212 is connected to an inner wall of the inner housing via an inner hatch cover connecting pin-shaft assembly 213, tightly pressed by an inner hatch cover press plate 93 mounted on the inner wall of the inner housing, and sealed by an O-shaped seal ring 211. An intermediate hatch cover 202 is connected to an outer wall of the inner housing via an intermediate hatch cover connecting pin-shaft assembly 203, tightly pressed by an intermediate hatch cover press plate 82 mounted on an outer wall of the intermediate housing, and sealed by an O-shaped seal ring 201. An outer hatch cover 192 is connected to an outer wall of the outer housing via an outer hatch cover connecting pin-shaft assembly 193, tightly pressed by an outer hatch cover press plate 72 mounted on the outer wall of the outer housing, and sealed by an O-shaped seal ring 191.

[0055] The inner hatch cover press plate 93 is connected to the inner housing via a mandrel assembly 91 and tightly pressed by a screw assembly 92; the intermediate hatch cover press plate 82 is connected to the intermediate housing via a mandrel assembly 81 and tightly pressed by a screw assembly 83; and the outer hatch cover press plate 72 is connected to the outer housing via a mandrel assembly 73 and tightly pressed by a screw assembly 71.

[0056] In order to ensure that the three hatch covers can be opened and closed smoothly, it is stipulated that diameters L.sub.1, L.sub.2, and L.sub.3 of the inner compartment hatch, the intermediate compartment hatch and the outer compartment hatch meet the following proportional relationship: 1:1:2, the diameter of the inner compartment hatch ranging from 0.7 m to 1.1 m.

[0057] The inner compartment is connected to an external auxiliary submersible via an inner compartment metal hose and connector assembly 14, an inner hatch cover hose connector 101, and an outer hatch cover hose connector 121, so as to maintain a standard air pressure in the inner compartment inside the inner housing. The intermediate compartment between the spherical inner housing and the spherical intermediate housing is connected to the external auxiliary submersible via an intermediate compartment metal hose and connector assembly 13, an intermediate hatch cover hose connector 111, and the outer hatch cover hose connector 121, so as to maintain a vacuum in the intermediate compartment between the inner housing and the intermediate housing. An outer compartment is connected to the external auxiliary submersible via the outer hatch cover hose connector 121, so as to maintain an air pressure in the outer compartment between the intermediate housing and the outer housing at a half of a hydraulic pressure outside the submersible at its working depth.

[0058] The outer hatch cover hose connector 121 is a three-tier metal connector in a nesting mode, with inner, middle, and outer tiers being respectively connected to the inner, intermediate, and outer compartments. The inner compartment metal hose and connector assembly for connecting an inner compartment metal hose 144 and the outer hatch cover hose connector 121 includes a nut 141, a seal ring 142, and a sealing bush 143. The inner compartment metal hose and connector assembly 14 for connecting the inner compartment metal hose 144 and the inner hatch cover hose connector 101 includes a sealing bush 145, a seal ring 146, and a nut 147. The intermediate compartment metal hose and connector assembly for connecting an intermediate compartment metal hose 134 and the outer hatch cover hose connector 121 includes a seal ring 132, a sealing bush 133, and a nut 131. The intermediate compartment metal hose and connector assembly for connecting the intermediate compartment metal hose 134 and the intermediate hatch cover hose connector 111 includes a sealing bush 135, a seal ring 136, and a nut 137. The three hatch cover hose connectors are all connected to the hatch covers through threads, and sealed by the O-shaped seal rings.

[0059] An assembly process of the present invention is as follows:

[0060] (1) Housings in Three Layers

[0061] A housing member in each layer is a hemispherical structure, and two hemispherical housings are connected via bolts or welded (a welding manner is used as an example in this embodiment) to form a complete spherical housing. During actual assembly of the housings in three layers, an inner hatch cover 7 and other large-sized apparatuses are placed between the two hemispherical structures of an inner housing, and then the two hemispherical members of the inner housing are connected and welded to form a complete inner housing.

[0062] Two intermediate compartment shafts 173 and 183 are symmetrically welded at two ends of the inner housing, and then, slide bearings 177 and 187 smeared with lubricating grease are mounted on the two shafts respectively. Intermediate compartment bearing press plates 174 and 184 are closed, and intermediate compartment bearing press plate screws 175 and 185 are screwed into the plates. Intermediate compartment bearing pedestals 172 and 182 are welded on inner walls of two hemispherical members of an intermediate housing respectively, and intermediate compartment spring dampers 171 and 181 are mounted on outer sides of the intermediate compartment bearing pedestals 172 and 182 respectively. Middle support plates of rotary limiting buffers 22 and 23 between the inner housing and the intermediate housing are symmetrically welded on an outer wall of the inner housing. Then, in each rotary limiting buffer, one end of each of two hydraulic dampers with universal joints is welded to a corresponding middle support plate, where the two ends are symmetrically arranged at two sides of the middle support plate; and the other end is welded at one side of a corresponding upper or lower support plate. Two symmetrical semi-pedestals of upper and lower support plate pedestals of the hydraulic dampers for connecting the inner housing and the intermediate housing are welded on rims of corresponding hemispherical housings respectively. The two hemispherical members of the intermediate housing that carry upper and lower support plate semi-pedestals of the hydraulic dampers, the intermediate compartment shaft pedestals, and the intermediate compartment spring dampers are assembled at two sides of the inner housing with the intermediate compartment shafts. The intermediate compartment shafts are made to be reliably fitted into inner holes of the intermediate compartment shaft pedestals via slide bearings and a bearing bush assembly. The upper and lower support plates of the hydraulic dampers are clamped in two corresponding semi-pedestals respectively, and then the two hemispherical members of the intermediate housing are welded to form a complete intermediate housing.

[0063] Two outer compartment shafts 153 and 163 are symmetrically welded at two ends of the intermediate housing, and then, slide bearings 157 and 167 smeared with lubricating grease are mounted on the two shafts respectively. Outer compartment bearing press plates 154 and 164 are closed, and outer compartment bearing press plate screws 155 and 165 are screwed into the plates. Outer compartment bearing pedestals 152 and 162 are welded on inner walls of two hemispherical members of an outer housing respectively, and outer compartment spring dampers 151 and 161 are mounted on outer sides of the outer compartment bearing pedestals 152 and 162 respectively. Middle support plates of rotary limiting buffers 24 and 25 between the intermediate housing and the outer housing are symmetrically welded on an outer wall of the intermediate housing. Then, in each rotary limiting buffer, one end of each of two hydraulic dampers with universal joints is welded to a corresponding middle support plate, where the two ends are symmetrically arranged at two sides of the middle support plate; and the other end is welded at one side of a corresponding upper or lower support plate. Two symmetrical semi-pedestals of upper and lower support plate pedestals of the hydraulic dampers for connecting the intermediate housing and the outer housing are welded on rims of corresponding hemispherical housings respectively. The two hemispherical members of the outer housing that carry upper and lower support plate semi-pedestals of the hydraulic dampers, the outer compartment shaft pedestals, and the outer compartment spring dampers are assembled at two sides of the intermediate housing with the outer compartment shafts. The outer compartment shafts are made to be reliably fitted into inner holes of the outer compartment shaft pedestals via slide bearings and a bearing bush assembly. The upper and lower support plates of the hydraulic dampers are clamped in two corresponding semi-pedestals respectively, and then the two hemispherical members of the outer housing are welded to form a complete outer housing.

[0064] (2) Hatch Covers in Three Layers

[0065] During actual assembly of hatch covers in inner, middle and outer layers and corresponding press plate assemblies, seal rings 211, 201, and 191 of the three hatch covers are first mounted. The inner hatch cover 212 that has been placed into the inner compartment is mounted on the inner housing via an inner hatch cover connecting pin-shaft assembly 213. An inner hatch cover press plate 93 is mounted on a mandrel assembly 91 of the inner hatch cover press plate, and then the shaft ends are clamped via retainer rings. After the inner hatch cover is closed, a screw assembly 92 is screwed into the inner hatch cover press plates. The intermediate hatch cover 202 is mounted on the intermediate housing via an intermediate hatch cover connecting pin-shaft assembly 203. An intermediate hatch cover press plate 82 is mounted on a mandrel assembly 81 of the intermediate hatch cover press plate, and then the shaft ends are clamped via retainer rings. After the intermediate hatch cover is closed, a screw assembly 83 is screwed into the intermediate hatch cover press plates. The outer hatch cover 192 is mounted on the outer housing via an outer hatch cover connecting pin-shaft assembly 193. An outer hatch cover press plate 16 is mounted on a mandrel assembly 73 of the outer hatch cover press plate, and then shaft ends are clamped via retainer rings. After the outer hatch cover is closed, a screw assembly 71 is screwed into the outer hatch cover press plates.

[0066] (3) Pipelines in Three Layers

[0067] During actual assembly of gas filling and exhaust pipelines and corresponding connectors, seal rings of hatch cover hose connectors in the three layers are mounted on corresponding hose connectors. The inner hatch cover hose connector 101, the intermediate hatch cover hose connector 111 and the outer hatch cover hose connector 121 are respectively mounted on the corresponding inner hatch cover 212, intermediate hatch cover 202 and outer hatch cover 192, and are screwed. The inner compartment hose assembly 14 runs through the intermediate compartment hose assembly 13 and the intermediate hatch cover hose connector 111. Two connectors of the inner compartment metal hose are respectively screwed onto the inner hatch cover hose connector 101 and the outer hatch cover hose connector 121. Two connectors of the intermediate compartment metal hose are respectively screwed onto the intermediate hatch cover hose connector 111 and the outer hatch cover hose connector 121.