A miniature low-power ultra-high-pressure buoyancy regulating device for underwater robots

Abstract

The present invention relates to a buoyancy regulating device, specifically a micro low-power ultra-high pressure buoyancy regulating device for an underwater robot, which is fixedly mounted on an end cover, and serves as both a pressure-resistant sealing structural member of the underwater robot and a hydraulic valve block of the entire buoyancy regulating system. The present invention utilizes a crankshaft to rotate and drive a micro single plunger unit to replace a finished hydraulic pump, effectively reducing the volume and weight of the buoyancy regulating device, and adopts a self-locking electromagnetic push rod in conjunction with a one-way valve to replace a finished hydraulic switch valve, and utilizes the rebound force of an outer oil bag to form a passive oil return system that consumes little energy, and a rolling diaphragm-type inner oil bag system with high buoyancy detection accuracy. The present invention has a simple structure, light weight (only 800g), high working pressure (70MPa), and low energy consumption, and is widely applicable to various conventional and micro underwater robots.

Description

Technical Field

[0001] The invention relates to a buoyancy regulating device, in particular to a miniature low-power consumption ultra-high pressure buoyancy regulating device for an underwater robot. Background Art

[0002] As an underwater measurement and operation platform, underwater robots have been widely used in marine scientific research, marine engineering, marine resource exploration, rescue and salvage and other application fields. Usually, underwater robots need to maintain a stable buoyancy state, such as a neutral state, during operation to ensure a normal and stable working state. However, affected by the change in seawater density, the buoyancy state of the underwater robot will fluctuate to varying degrees, thus affecting the overall performance of the underwater robot. Through a dedicated underwater robot buoyancy adjustment device, the displacement volume of the underwater robot is automatically adjusted according to the seawater density of the underwater robot operation area to achieve the desired buoyancy state. During the operation of the underwater robot, the power consumption of the buoyancy adjustment system often accounts for more than 50%. As underwater robots continue to develop in the direction of high depth, low power consumption, long endurance, and lightweight, higher requirements are also put forward for the buoyancy adjustment system. Therefore, the study of modular, high-pressure, miniaturized, high-precision, low-power, stable and reliable underwater robot buoyancy adjustment devices plays an important role in improving the overall performance of the water robot. Summary of the invention

[0003] The purpose of the present invention is to provide a miniature low-power ultra-high pressure buoyancy regulating device for an underwater robot. The buoyancy regulating device has reliable operation, high regulating accuracy, a maximum operating depth of 7,000 meters, and a total weight of less than 800 grams.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The present invention includes a buoyancy motor sealing shell, a buoyancy drive motor, an inner oil bag piston, a rolling diaphragm, an inner oil bag shell, a miniature single plunger unit, an oil outlet check valve, a crankshaft, a self-locking electromagnetic push rod, an end cover, an oil return check valve, an outer oil bag and an inner oil bag bottom cover, wherein the end cover is sealingly installed on the underwater robot, and the end cover is respectively installed with an oil outlet check valve and an oil return check valve, one side of the inner oil bag shell is connected to the inner side of the end cover, and the other side of the inner oil bag shell is connected to the inner oil bag bottom cover; the buoyancy drive motor and the buoyancy motor sealing shell are both penetrated by the inner oil bag bottom cover, the buoyancy drive motor is installed on the end cover, the output shaft is connected to the crankshaft rotatably installed on the end cover, and the buoyancy drive motor is outer-coated with a buoyancy motor sealing shell sealingly installed on the end cover ; The inner oil bag piston is sleeved on the buoyancy motor sealing shell and is sealed and slidably connected to the buoyancy motor sealing shell. One side of the rolling diaphragm is sealed and connected to the end cover, and the other side is sealed and connected to the inner oil bag piston; the miniature single-plunger unit and the self-locking electromagnetic push rod are respectively installed on the inner side of the end cover, and the outer oil bag is installed on the outer side of the end cover. The miniature single-plunger unit corresponds to the oil outlet check valve, and the self-locking electromagnetic push rod corresponds to the oil return check valve. The buoyancy drive motor drives the crankshaft to rotate, and the crankshaft pushes the piston of the miniature single-plunger unit to reciprocate, so that the hydraulic oil in the inner oil bag is pumped into the outer oil bag through the oil outlet check valve, and the hydraulic oil in the outer oil bag flows back to the inner oil bag through the self-locking electromagnetic push rod acting on the oil return check valve.

[0006] Wherein: the axial center line of the concentric part of the crankshaft is colinear with the axial center line of the end cover, the eccentric shaft part of the crankshaft is sleeved with a deep groove ball bearing B, and the crankshaft is in rolling contact with the piston in the miniature single plunger unit through the deep groove ball bearing B.

[0007] An end cover oil outlet is provided on the inner side of the end cover, one side of the end cover oil outlet is opposite to the plunger pump oil outlet of the micro single plunger unit, and an O-type axial sealing ring is used to seal the plunger pump oil outlet and the end cover oil outlet; the oil outlet check valve is screwed into the end cover through a threaded hole opened on the outer side of the end cover, and the other side of the end cover oil outlet is opposite to the oil outlet check valve.

[0008] The output shaft of the buoyancy drive motor is connected to the crankshaft through a coupling, and a skeleton oil seal is used to provide a rotating seal for the crankshaft.

[0009] A radial O-ring is provided on one side of the rolling diaphragm, and the radial O-ring is sleeved in a radial sealing groove opened on the end cover. An axial O-ring is provided on the other side of the rolling diaphragm, and the axial O-ring is accommodated in an axial sealing groove opened on the inner oil bag piston and fixed to the inner oil bag piston through a clamping plate.

[0010] A buoyancy potentiometer is installed on the bottom cover of the inner oil bag.

[0011] The end cover is provided with an oil filling plug for filling oil into the inner oil bag.

[0012] A star-shaped ring is used as a dynamic seal between the inner oil bag piston and the buoyancy motor sealing shell.

[0013] The advantages and positive effects of the present invention are:

[0014] 1. The present invention adopts a buoyancy-driven motor to directly drive the reciprocating motion of the piston of the micro single-plunger unit, replacing the finished plunger pump; a self-locking electromagnetic push rod is used in conjunction with a micro-inserted oil return one-way valve to replace the finished electromagnetic switch valve. These two designs effectively reduce the volume and weight of the device, with a total mass of only 800 grams.

[0015] 2. The present invention has a high pressure rating, and the maximum working pressure can reach 70Mpa, which can meet the deep-water operation requirements of most underwater robots.

[0016] 3. The present invention adopts a self-locking electromagnetic push rod and cooperates with the rebound force of the outer oil bag to return oil. The oil return process has basically zero power consumption, which effectively reduces the power consumption of the buoyancy adjustment system. The oil discharge efficiency of the buoyancy adjustment system is more than 55%.

[0017] 4. The present invention adopts a rolling diaphragm type inner oil bag structure, and the rolling friction resistance of the rolling diaphragm during operation is small and the cylindricity is good; at the same time, a buoyancy potentiometer is used to detect the position of the inner oil bag piston, and the buoyancy change linearity is good, and the buoyancy size can be accurately controlled.

[0018] 5. The present invention has a large buoyancy adjustment capability, and the maximum buoyancy adjustment amount can be flexibly adjusted by adjusting the volumes of the inner and outer oil bags. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural principle diagram of the present invention;

[0020] Figure 2 It is a cross-sectional view of the structure of the present invention (the outer oil bag is in the smallest state);

[0021] Figure 3 It is a structural cross-sectional view of the present invention (the outer oil bag is in the largest state);

[0022] Among them: 1 is a buoyancy potentiometer, 2 is a buoyancy motor sealing shell, 3 is a buoyancy drive motor, 4 is an inner oil bag piston, 5 is a rolling diaphragm, 6 is an inner oil bag outer shell, 7 is a cross slide coupling, 8 is a miniature single plunger unit, 9 is an oil outlet check valve, 10 is a crankshaft, 11 is a self-locking electromagnetic push rod, 12 is an end cover, 13 is an oil filling plug, 14 is an oil return check valve, 15 is an outer oil bag, 16 is an inner oil bag bottom cover, 17 is a plunger pump oil outlet, 18 is an end cover oil outlet, 19 is a threaded hole, 20 is a deep groove ball bearing A, 21 is a deep groove ball bearing B, and 22 is a clamping plate. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] like Figures 1 to 3 As shown, the present invention includes a buoyancy potentiometer 1, a buoyancy motor sealing shell 2, a buoyancy drive motor 3, an inner oil bag piston 4, a rolling diaphragm 5, an inner oil bag shell 6, a coupling, a miniature single plunger unit 8, an oil outlet check valve 9, a crankshaft 10, a self-locking electromagnetic push rod 11, an end cover 12, an oil filling plug 13, an oil return check valve 14, an outer oil bag 15 and an inner oil bag bottom cover 16. The end cover 12 of this embodiment is a fixed support. The end cover 12 can be installed on the underwater robot as a pressure-resistant end cover seal of the underwater robot, and also serves as a valve block of the hydraulic system. The oil circuits of the hydraulic system are all processed on the end cover 12, which effectively reduces the number of parts and system complexity of the buoyancy adjustment device.

[0025] The end cover 12 is respectively installed with an oil outlet check valve 9 and an oil return check valve 14. One side of the inner oil bag shell 6 is connected to the inner side of the end cover 12, and the other side of the inner oil bag shell 6 is connected to the inner oil bag bottom cover 16; the buoyancy drive motor 3 and the buoyancy motor sealing shell 2 are both penetrated by the inner oil bag bottom cover 16, the buoyancy drive motor 3 is installed on the end cover 12, and the output shaft is connected to the crankshaft 10 rotatably installed on the end cover 12. The buoyancy drive motor 3 is covered with a buoyancy motor sealing shell 2 that is sealed and installed on the end cover 12; the inner oil bag piston 4 is sleeved on the buoyancy motor sealing shell 2 and is sealed and slidably connected to the buoyancy motor sealing shell 2. One side of the rolling diaphragm 5 is connected to the end cover 12 is sealed and connected, and the other side is sealed and connected with the inner oil bag piston 4; the micro single plunger unit 8 and the self-locking electromagnetic push rod 11 are respectively installed on the inner side of the end cover 12, and the outer oil bag 15 is installed on the outer side of the end cover 12. The micro single plunger unit 8 corresponds to the oil outlet check valve 9, and the self-locking electromagnetic push rod 11 corresponds to the oil return check valve 14. The buoyancy drive motor 3 drives the crankshaft 10 to rotate, and the crankshaft 10 pushes the piston of the micro single plunger unit 8 to reciprocate, and the hydraulic oil in the inner oil bag is pumped into the outer oil bag 15 through the oil outlet check valve 9. The hydraulic oil in the outer oil bag 11 flows back to the inner oil bag through the self-locking electromagnetic push rod 11 acting on the oil return check valve 14.

[0026] The two ends of the crankshaft 10 of this embodiment are rotatably mounted on the end cover 12 through two deep groove ball bearings A20. The axial center line of the concentric part of the crankshaft 10 is colinear with the axial center line of the end cover 12. At the same time, two deep groove ball bearings B21 are sleeved on the eccentric shaft part of the crankshaft 10. The crankshaft 10 is in rolling contact with the piston in the miniature single plunger unit 8 through the deep groove ball bearings B21, thereby converting the sliding friction between the crankshaft 10 and the plunger in the process of rotating and pushing the plunger into rolling friction, effectively improving the working efficiency of the system.

[0027] The micro single plunger unit 8 of this embodiment is fixedly connected to the end cover 12 by two M6 screws, and an end cover oil outlet 18 is provided on the inner side of the end cover 12, one side of the end cover oil outlet 18 is opposite to the plunger pump oil outlet 17 of the micro single plunger unit 8, and an O-type axial sealing ring is used between the plunger pump oil outlet 17 and the end cover oil outlet 18 to play a sealing role; the oil outlet check valve 9 is screwed into the end cover 12 through the threaded hole 19 opened on the outer side of the end cover 12, and the other side of the end cover oil outlet 18 is opposite to the oil outlet check valve 9. The pressure oil generated by the micro plunger unit 8 can flow into the outer oil bag 15 through the oil outlet check valve 9, but cannot flow in the reverse direction.

[0028] The buoyancy drive motor 3 of this embodiment is fixed to the end cover 12 through a bell-shaped cover, and the output shaft of the buoyancy drive motor 3 is connected to the crankshaft 10 through a coupling, and a skeleton oil seal is used to provide a rotating seal for the crankshaft 10; the coupling of this embodiment is a cross slot coupling 7. Then, the buoyancy motor sealing shell 2 is sleeved on the outside of the buoyancy drive motor 3 and fixed to the end cover 12 by screws. A radial O-ring seal is used between the end cover 12 and the buoyancy motor sealing shell 2 to isolate the oil in the inner oil bag from the buoyancy drive motor 3. The rotation of the buoyancy drive motor 3 drives the crankshaft 10 to rotate, thereby driving the piston of the micro single plunger unit 8 to reciprocate up and down, and then pumping the oil in the inner oil bag into the outer oil bag 15.

[0029] The oil return check valve 14 of this embodiment is screwed into the end cover 12 through the threaded hole 19 opened on the inner side of the end cover 12, and the self-locking electromagnetic push rod 11 is also installed on the end cover 12 through the fixing member. Under normal conditions, the hydraulic oil in the outer oil bag 15 cannot flow back to the inner oil bag through the oil return check valve 14, and the push rod of the self-locking electromagnetic push rod 11 can reciprocate when powered on; when powered on in the forward direction, the push rod of the self-locking electromagnetic push rod 11 extends to push open the valve core of the oil return check valve 14, so that reverse flow can be performed. At this time, under the action of the rebound force of the outer oil bag 15, the push rod of the self-locking electromagnetic push rod 11 remains in the extended state after power failure until the oil return process is completed; then reverse power is applied, the push rod of the self-locking electromagnetic push rod 11 retracts, and the push rod of the self-locking electromagnetic push rod 11 remains in the retracted state after power failure, and the oil return check valve 14 is closed. An oil filling plug 13 for filling oil into the inner oil bag is provided on the end cover 12.

[0030] The outer oil bag 15 of the present embodiment is made of rubber with high elasticity. When the oil bag is vulcanized, it is provided with a radial O-ring and is fixedly mounted on the end cover 12 by a snap ring.

[0031] One side of the rolling diaphragm 5 of this embodiment is provided with a radial O-ring, which is sleeved in a radial sealing groove provided on the end cover 12. The other side of the rolling diaphragm 5 is provided with an axial O-ring, which is accommodated in an axial sealing groove provided on the inner oil bag piston 4 and fixed to the inner oil bag piston 4 through a clamping plate 22. The rolling diaphragm 5 and the inner oil bag piston 4 are sealed by the axial O-ring provided on the rolling diaphragm 5. The radial O-ring of the rolling diaphragm 5 is sleeved in the radial sealing groove of the end cover 12. The rolling diaphragm 5 is then subjected to a convolution process, and the inner oil bag housing 6 is sleeved on the outer side of the rolling diaphragm 5 and fixedly connected to the end cover 12 by screws. The inner oil bag bottom cover 16 is fixed to the inner oil bag housing 6 by screws, and the buoyancy potentiometer 1 is fixed to the inner oil bag bottom cover 16 by screws. The inner oil bag piston 4 can slide back and forth on the buoyancy motor sealing shell 2 during operation, and the buoyancy motor sealing shell 2 plays a good guiding role to prevent the piston from deflecting and causing inaccurate measurement. A star ring is used as a dynamic seal between the inner oil bag piston 4 and the buoyancy motor sealing shell 2.

[0032] The miniature single plunger unit 8 of the present invention is a commercial product purchased from Germany's Hawe Company, model number MPE4. The self-locking electromagnetic push rod 11 of the present invention is a commercial product purchased from Shenzhen Zongtai Electromechanical Co., Ltd., model number SDK2-0734S-12A09-09.

[0033] The working principle of the present invention is:

[0034] When the underwater robot needs to increase the displacement volume of the carrier, the hydraulic oil in the inner oil bag needs to be discharged into the outer oil bag 15. At this time, the push rod of the self-locking electromagnetic push rod 11 remains retracted and the oil return check valve 14 is closed. The buoyancy drive motor 3 is powered on and rotates, driving the crankshaft 10 to rotate through the cross slot coupling 7. During the rotation process, the crankshaft 10 pushes the piston of the micro single plunger unit 8 to reciprocate, realizing the oil suction and discharge action, and pumping the hydraulic oil in the inner oil bag into the outer oil bag 15 through the oil outlet check valve 14. Figure 2 The status becomes Figure 3 In the state shown, the drainage volume of the outer oil bag 15 is increased.

[0035] When the underwater robot needs to reduce the displacement volume of the carrier to achieve diving action on the water surface, the self-locking electromagnetic push rod 11 applies a pulse voltage (about 50ms) in the positive direction. At this time, the push rod of the self-locking electromagnetic push rod 11 extends, overcoming the elastic force of the return spring in the valve core of the return oil check valve 14 and pushing the valve core open, so that the return oil check valve 14 can flow in the reverse direction. Under the rebound force of the outer oil bag 15, the hydraulic oil passively flows back to the inner oil bag through the return oil check valve 14, and the hydraulic oil is driven by the outer oil bag 15. Figure 3 The status becomes Figure 2 In the state shown, the drainage volume of the outer oil bag 15 is reduced.

Claims

1. A miniature low-power ultra-high-pressure buoyancy regulating device for an underwater robot, characterized in that: The invention comprises a buoyancy motor sealing shell (2), a buoyancy drive motor (3), an inner oil bag piston (4), a rolling diaphragm (5), an inner oil bag outer shell (6), a micro single plunger unit (8), an oil outlet check valve (9), a crankshaft (10), a self-locking electromagnetic push rod (11), an end cover (12), an oil return check valve (14), an outer oil bag (15) and an inner oil bag bottom cover (16), wherein the end cover (12) is sealed and installed on the underwater robot, and the oil outlet check valve (9) and the oil return check valve are respectively installed on the end cover (12). (14), one side of the inner oil bladder shell (6) is connected to the inner side of the end cover (12), and the other side of the inner oil bladder shell (6) is connected to the inner oil bladder bottom cover (16); the buoyancy drive motor (3) and the buoyancy motor sealing shell (2) are both inserted through the inner oil bladder bottom cover (16), the buoyancy drive motor (3) is mounted on the end cover (12), the output shaft is connected to the crankshaft (10) rotatably mounted on the end cover (12), and the buoyancy drive motor (3) has a seal mounted on the end cover (12). The buoyancy motor sealing shell (2) is provided with a buoyancy motor sealing shell (2); the inner oil bag piston (4) is sleeved on the buoyancy motor sealing shell (2) and is sealingly and slidably connected to the buoyancy motor sealing shell (2); one side of the rolling diaphragm (5) is sealingly connected to the end cover (12), and the other side is sealingly connected to the inner oil bag piston (4); the miniature single plunger unit (8) and the self-locking electromagnetic push rod (11) are respectively installed on the inner side of the end cover (12); the outer oil bag (15) is installed on the outer side of the end cover (12); the miniature single plunger unit (8) Corresponding to the oil outlet check valve (9), the self-locking electromagnetic push rod (11) corresponds to the oil return check valve (14), the buoyancy drive motor (3) drives the crankshaft (10) to rotate, and the crankshaft (10) pushes the piston of the micro single plunger unit (8) to reciprocate, so that the hydraulic oil in the inner oil bag is pumped into the outer oil bag (15) through the oil outlet check valve (9), and the hydraulic oil in the outer oil bag (15) flows back to the inner oil bag through the self-locking electromagnetic push rod (11) acting on the oil return check valve (14); The axial centerline of the concentric part of the crankshaft (10) is colinear with the axial centerline of the end cover (12); the eccentric shaft part of the crankshaft (10) is sleeved with a deep groove ball bearing B (21); the crankshaft (10) is in rolling contact with the piston in the miniature single plunger unit (8) via the deep groove ball bearing B (21); An end cover oil outlet (18) is provided on the inner side of the end cover (12), one side of the end cover oil outlet (18) is opposite to the plunger pump oil outlet (17) of the micro single plunger unit (8), and an O-type axial sealing ring is used to seal between the plunger pump oil outlet (17) and the end cover oil outlet (18); the oil outlet check valve (9) is screwed into the end cover (12) through a threaded hole (19) provided on the outer side of the end cover (12), and the other side of the end cover oil outlet (18) is opposite to the oil outlet check valve (9); The output shaft of the buoyancy drive motor (3) is connected to the crankshaft (10) via a coupling, and a skeleton oil seal is used to provide a rotation seal for the crankshaft (10); A radial O-type sealing ring is provided on one side of the rolling diaphragm (5), and the radial O-type sealing ring is sleeved in a radial sealing groove provided on the end cover (12). An axial O-type sealing ring is provided on the other side of the rolling diaphragm (5), and the axial O-type sealing ring is accommodated in an axial sealing groove provided on the inner oil bag piston (4), and is fixed to the inner oil bag piston (4) via a clamping plate (22).

2. According to claim 1, the micro low-power ultra-high-pressure buoyancy regulating device for an underwater robot is characterized in that: A buoyancy potentiometer (1) is mounted on the inner oil bladder bottom cover (16).

3. According to claim 1, the micro low-power ultra-high-pressure buoyancy regulating device for an underwater robot is characterized in that: The end cover (12) is provided with an oil injection plug (13) for injecting oil into the inner oil bag.

4. According to claim 1, the micro low-power ultra-high-pressure buoyancy regulating device for an underwater robot is characterized in that: A star-shaped ring is used as a dynamic seal between the inner oil bag piston (4) and the buoyancy motor sealing shell (2).

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