GB2603428A

GB2603428A - Intelligent underwater bulldozer and cooling system thereof

Info

Publication number: GB2603428A
Application number: GB2205912.5A
Authority: GB
Inventors: Li Yong; Chen Qiang; He Dingchang; Si Qiaorui
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2020-10-28
Filing date: 2020-11-24
Publication date: 2022-08-03
Anticipated expiration: 2040-11-24
Also published as: WO2022088322A1; CN112431243B; CN112431243A; GB2603428B; GB202205912D0

Abstract

The present invention relates to the technical field of manufacturing of intelligent underwater bulldozers, and provides an intelligent underwater bulldozer and a cooling system thereof. The cooling system comprises a hydraulic oil cooling system and an electric and electronic component cooling system; the hydraulic oil cooling system comprises a hydraulic oil tank, a power unit, a test unit, and a heat exchanger; the test unit is used for measuring the temperature of hydraulic oil and an instantaneous flow rate of the hydraulic oil in a cooling pipe; the heat exchanger is used for performing heat exchange between the two cooling systems and the outside and performing heat exchange between the two cooling systems; the electric and electronic component cooling system has two parallel water paths, and a sequence in which a cooling liquid flows through heat dissipation components is arranged according to heat generated by a component to be cooled and heat dissipation demands. According to the presents invention, a weak-demand cooling system for electric and electronic components is used for assisting a strong-demand cooling system for heat dissipation, and the present invention has the advantages of a simple structural design and an obvious heat dissipation effect.

Description

INTELLIGENT UNDERWATER BULLDOZER AND COOLING SYSTEM

THEREOF

Technical Field

The present invention belongs to the technical field of intelligent underwater bulldozer manufacturing, and relates to an intelligent underwater bulldozer and a cooling system thereof

Background

Intelligent underwater bulldozer is a kind of fully sealed intelligent construction machinery for underwater operation, which is powered by cables for motor drive system and other power electronic devices, making it get rid of the problem of working underwater for traditional internal combustion engine type amphibious operation machinery, greatly improving its working efficiency and flexibility. The intelligent underwater bulldozer's walking motion is driven by the power outputting from hydraulic motor, which is driven by the hydraulic pump. The power is transferred to the sprocket installed coaxially with the hydraulic motor to drive the crawler. The movement of the intelligent underwater bulldozer is driven by the hydraulic pump driven by the drive motor, using the hydraulic cylinder to make the bulldozer bucket and rocker arm move, so that the bucket can tilt and lift to complete the engineering tasks, such as pushing soil, loading soil etc. Under complex working conditions, the drive motor, hydraulic pump and other power electronics of the intelligent underwater bulldozer will generate a lot of heat. Since the power compartment of the intelligent underwater dozer is in a sealed state, the heat dissipation of power compartments faces serious challenges. The high temperature not only threatens the operational safety of the drive system, but also makes the hydraulic oil viscosity drop and the system leakage serious, resulting in low efficiency of the hydraulic system. In addition, the power electronics are more likely to be destabilized and reduced their service life when working at high temperature.

Intelligent underwater bulldozers have high requirements on the sealing of the powerhouse, and the traditional air-cooled cooling method cannot be applied to such construction machinery as intelligent underwater bulldozers, which generate more heat and have difficulty in local cooling. Therefore, the design of an intelligent cooling system with significant heat dissipation effect, which is applicable to the sealed working machine of the powerhouse, is essential to improve the efficiency and reliability of the intelligent underwater bulldozer.

The power electronics components and hydraulic oil of the intelligent underwater bulldozers work with different needs of heat production and heat dissipation, so their cooling systems need to be designed separately. in fact, the heat dissipation demand of power electronic components is relatively small, while the heat dissipation demand of hydraulic oil is large. How can we use the weak demand cooling system to assist the strong cooling system to optimize the cooling effect? At present, the cooling structure with this feature is difficult to be reflected in the underwater unmanned bulldozer.

Summary

In response to the shortcomings of the prior technology, the present invention proposes an intelligent underwater bulldozer and a cooling system thereof, which makes full use of the working environment underwater. It can achieve heat dissipation without fans, and use of weak demand power electronic component cooling system to assist the strong demand cooling system heat dissipation, with the characteristics of simple structure and obvious heat dissipation effect, but also broaden the design of cooling system of the few underwater operation equipment.

The present invention achieves the above technical purpose by the following technical means. A cooling system for an intelligent underwater bulldozer comprises a hydraulic oil cooling system and a power electronic class component cooling system The proposed hydraulic oil cooling system comprises a hydraulic oil tank, a power unit, a detection unit and a heat exchanger.

The proposed hydraulic oil tank is in communication with the hydraulic cylinder, passing through the second centrifugal pump. The proposed hydraulic oil tank is also in communication with the bi-directional variable hydraulic motor, passing through the third centrifugal pump.

The proposed power unit comprises a first oil pump motor, a first motor controller and a first centrifugal pump. The first oil pump motor in signal transmission with the first motor controller, and the first motor controller in signal transmission with the electronic control unit for signal transmission. The first oil pump motor is in communication with the first centrifugal pump. The oil inlet of the first centrifugal pump is in communication with the third outlet of the hydraulic oil tank, and the oil outlet of the first centrifugal pump is in communication with the oil radiator inlet.

The proposed detection unit comprises a first oil temperature sensor and a second oil temperature sensor. The first oil temperature sensor is installed between the first oil outlet of the hydraulic oil tank and the second oil outlet of the oil tank. And the second oil temperature sensor is installed on the oil pipe between the third oil inlet of the oil tank and the outlet of oil radiator.

The proposed heat exchanger comprises an oil radiator and a coolant radiator, and the oil radiator and coolant radiator are encapsulated. The oil radiator comprises an oil inlet chamber, an oil outlet chamber, a first partition, an inlet of oil radiator, an outlet of oil radiator and the number of oil pipes. The oil inlet chamber and the oil outlet chamber are separated by a first partition. The inlet of oil radiator is set on oil inlet chamber and the outlet of oil radiator is set on oil outlet chamber. The oil inlet chamber is in communication with the inlet of oil pipes, and the oil outlet chamber is in communication with the outlet of oil pipes. The coolant radiator comprises a water inlet chamber, a water outlet chamber, a second partition, a coolant radiator inlet, a coolant radiator outlet, the number of water pipes and an expansion pipe inlet. The water inlet chamber and the water outlet chamber are separated by the second partition, and a coolant radiator inlet is opened above the water inlet chamber. The water inlet chamber is in communication with the inlet of the radiator pipe. A coolant radiator outlet is opened above the water outlet chamber of the coolant radiator, and the water outlet chamber is in communication with the outlet of the radiator pipe. An expansion pipe inlet is opened above the water inlet chamber, and the expansion pipe inlet is in communication with the inlet of the expansion water tank; the oil pipes of oil radiator and the water pipes of coolant radiator are staggered. Many oil pipes of oil radiator are connected and many water pipes of coolant radiator are connected. Adjacent oil pipe of oil radiator and water pipe of coolant radiator are separated by a radiator core.

The proposed power electronic component cooling system comprises a water pump motor, a fourth motor controller, a fourth centrifugal pump, a second flow meter, an expansion tank, a first water temperature sensor, a second water temperature sensor and a third water temperature sensor.

The proposed fourth centrifugal pump inlet is in communication with the coolant radiator outlet and the third water temperature sensor is installed on the water pipe. The fourth centrifugal pump is fixedly connected to the pump motor, which is controlled by the fourth motor controller, which transmits signals to the electronic control unit.

The proposed power electronic component cooling system is divided into two parallel water paths. The first parallel water path flows through the fourth centrifugal pump, battery pack, variable voltage rectification module, power distribution module, coolant radiator and the fourth centrifugal pump. The second parallel water path flows in the order of the fourth centrifugal pump, the fourth motor controller and pump motor, the third oil pump motor and the third motor controller, the second oil pump motor and second motor controller, the first oil pump motor and first motor controller, the coolant radiator, and the fourth centrifugal pump.

At the convergence of the first parallel water path and the second parallel water path, a first water temperature sensor is installed on the second parallel water path, and a second water temperature sensor is installed on the main path after the convergence of the two parallel water paths.

The second flow meter is installed on the line between proposed fourth centrifugal pump and the battery pack.

In a further technical scheme, the proposed the cross-sectional shapes of oil pipes of oil radiator and water pipe of coolant radiator are both rectangular.

In a further technical scheme, the proposed oil radiator and the coolant radiator are encapsulated as a unit by means of the shell of the heat exchanger accessory.

In a further technical scheme, the oil radiator outlet is in communication with the third oil inlet of the hydraulic oil tank by a pipe, where the first check valve is installed.

In a further technical scheme, the proposed detection unit also comprises a third oil temperature sensor, a fourth oil temperature sensor and a first flow meter, wherein the proposed third oil temperature sensor is installed at the oil outlet of the second centrifugal pump, and the proposed fourth oil temperature sensor is installed at the oil outlet of the third centrifugal pump, and the proposed first flow meter is installed at the oil outlet of the first centrifugal pump.

In a further technical scheme, a flow control valve is installed at the entrance of proposed second parallel water path inlet, wherein the proposed flow control valve comprises thermal material, valve body, preload spring, valve seat, first guide block, flow control valve inlet and flow control valve outlet. The flow control valve housing is provided with thermal material on one side, and the thermal material is in contact with the front end of the valve body. The front end of the valve body is supported by a first guide block, and the rear end of the valve body is movably connected to the valve seat, and the end of the valve body is supported by a second guide block, and the rear end of the valve body is also fixed to the flow control valve housing by a preload spring.

In a further technical scheme, a third check valve is also installed on the second parallel water path.

In a further technical scheme, the proposed the expansion tank outlet is in communication with the main waterway of the power electronic component cooling system, and the second check valve is installed in the main waterway.

An intelligent underwater bulldozer comprises the proposed cooling system.

The present invention provides an intelligent underwater bulldozer and a cooling structure, and the beneficial effect is as follows: (I) The present invention provides a cooling structure of an intelligent underwater bulldozer. The hydraulic oil cooling system and the power electronic component cooling system operate independently, but their radiators are encapsulated as a unit. The hydraulic oil to be cooled can not only exchange heat with the external water environment, but also exchange heat with the coolant, which enhances the cooling effect of the hydraulic oil. This process, which does not require the use of electric fans, avoids the disadvantages of using fans in a sealed underwater environment and has energy-saving features.

(2) The present invention provides a cooling structure of an intelligent underwater bulldozer. The hydraulic oil cooling system is an independent cooling system, cooling from the root of the oil. The cooling process is not related to the work of each hydraulic subsystem, and the working state of the hydraulic subsystem does not affect its cooling effect. In addition, the pipes of the hydraulic subsystem can be designed to be shorter, with less resistance, reducing the delay and damage of mechanical parts.

(3) The present invention provides a cooling structure of an intelligent underwater bulldozer. The cooling of power electronic components is divided into two parallel water paths, and the flow control valve of the second parallel water path can adaptively change the flow of coolant in the second parallel water path according to the heat dissipation demand of the second parallel water path. When the heat dissipation demand of the second parallel water path is small, the flow of coolant in the second parallel path is reduced, so the cooling effect of the first parallel cooling path is enhanced while the flow of main waterway remains unchanged, which enables full use of cooling requirements to improve the overall cooling capacity of the intelligent underwater bulldozers.

Brief Description of the Drawings

FIG. I illustrates a structural diagram of the intelligent underwater bulldozer in the present invention FIG. 2 illustrates a structural diagram of the cooling system of the intelligent underwater bulldozer in the present invention FIG. 3 illustrates a top view of the structure of the hydraulic oil tank described in the present invention FIG. 4 illustrates a top view of the encapsulated structure of the hydraulic oil radiator and coolant radiator described in the present invention.

FIG. 5 illustrates a front view of the encapsulated structure of the hydraulic oil radiator and coolant radiator described in the present invention.

FIG. 6 illustrates a structural diagram of the flow control valve described in the present invention The reference numerals of accompanying drawings are described as follows: I -first oil pump motor, 2-first motor controller, 3-first centrifugal pump, 4-first flow meter, 5-oil radiator, 5. I -oil inlet chamber, 5.2-oil outlet chamber, 5.3-first partition, 5.4-oil radiator inlet, 5.5-oil radiator outlet, 5.6-dissipative oil pipe, 6-first oil temperature sensor, 7-second oil temperature sensor, 8-first check valve, 9-hydraulic oil tank, 9. I -first oil inlet, 9.2-second oil inlet, 9.3-third oil inlet, 9.4-fourth oil inlet, 9.5-first oil outlet, 9.6-second oil outlet, 9.7-third oil outlet, 10-second oil pump motor, 11-second motor controller, 12-second centrifugal pump, 13-third oil temperature sensor, 14-first reversing valve, 15-hydraulic cylinder, 16-third oil pump motor, 17-third motor controller, I 8-third centrifugal pump, I 9-fourth oil temperature sensor, 20-second reversing valve, 21-bidirectional variable hydraulic motor, 22-first hydraulic subsystem distribution valve, 23-second hydraulic subsystem distribution valve, 24-water pump motor, 25-fourth motor controller, 26-fourth centrifugal pump, 27-coolant radiator, 27.1-water inlet chamber, 27.2-water outlet chamber, 27.3-second partition, 27.4-coolant radiator inlet, 27.5-coolant radiator outlet, 27.6-radiator water pipe, 27.7-expansion pipe inlet, 28-flow control valve, 28. I -thennosensitive material, 28.2-valve body, 28.3-preload spring, 28.4-valve seat, 28.5-first guide block, 28.6-flow control valve inlet, 28.7-flow control valve outlet, 29-second flow meter, 30-expansion tank, 3 I -first water temperature sensor, 32-second water temperature sensor, 33-third water temperature sensor, 34-second check valve, 35-third check valve, 36-battery pack, 37-variable voltage rectification module, 38-power distribution module, 39-heat exchanger accessories, 39. I -housing, 39.2-radiator core, 39.3-pressure plate, 39.4-screws.

Detailed Description of the Embodiments

The present invention is further described below in connection with the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to this.

Referring to FIG. 1, the intelligent underwater bulldozer has the sealed structure, and the hydraulic drive system and power electronic equipment of the intelligent underwater bulldozer are completely isolated from the external water environment through sealing materials. Internal air flow is poor, so it cannot be forced to dissipate heat through the cooling fan; and the cooling needs of the hydraulic oil in the hydraulic drive system and the cooling needs of power electronics are different when the intelligent underwater bulldozer is working, so the present invention designs a cooling system for the intelligent underwater bulldozer.

Referring to FIG. 2, a cooling system of an intelligent underwater bulldozer comprises a hydraulic oil cooling system and power electronic component cooling system, and the two cooling systems are carried out separately; the hydraulic oil cooling system directly pumps the transmission oil to be cooled from the tank and dissipates heat in the oil radiator; the power electronic component cooling system takes away the heat from power electronic components in turn by pumping coolant, and dissipates heat in coolant radiator: the pipes of two radiators are overlapped to exchange heat and achieve a weak demand cooling system to assist the strong demand cooling system to dissipate heat. The two cooling systems are described in detail below: Referring to FIG. 2, the hydraulic oil cooling system comprises hydraulic oil tank 9, power unit, detection unit and heat exchanger.

FIG. 3 shows the hydraulic oil tank 9 is provided with three oil outlets and four oil inlets, and the heights of the oil outlets are all lower than the oil inlets; the positions of the first oil inlet 9.1, the second oil inlet 9.2, and the third oil inlet 9.3 are all set at 2/3 of the height of the oil tank, and the first oil inlet 9.1 is in communication with the two oil return passage ports of the first reversing valve 14 through oil pipes, and the third oil inlet 9.3 is in communication with radiator outlet 5.5; the fourth inlet port 9.4 is located at the top of the hydraulic oil tank 9 for hydraulic oil replenishment manually when the tank 9 is a low oil state; the positions of the first outlet 9.5, the second outlet 9.6 and the third outlet 9.7 are all set at 1/3 of the height of the oil tank, the first outlet 9.5 is in communication with the second centrifugal pump 12 through an oil pipe to provide hydraulic oil for the activity of the hydraulic cylinder 15, and the second outlet 9.6 is in communication with the third centrifugal pump 18 through an oil pipe to provide hydraulic oil for the bidirectional variable hydraulic motor variable hydraulic motor 21 to drive the coaxially mounted sprocket. The third outlet 9.7 is in communication with the inlet of the first centrifugal pump 3, and the oil to be cooled reaches the oil radiator 5 passing through the third outlet 9.7 for heat exchange with the external water environment.

Referring to FIG. 2, The power unit comprises a first oil pump motor 1, a first motor controller 2 and a first centrifugal pump 3; the first oil pump motor 1 in signal transmission with the first motor controller 2 through twisted pair cable, the first motor controller 2 in signal transmission with the electronic control unit for signal transmission, and the first oil pump motor 1 is mechanically connected to the first centrifugal pump 3 by spline, and the oil outlet of the first centrifugal pump 3 is in communication with the oil radiator inlet 5.4 by oil pipe, and the power unit provides power for the circulation cooling of the hydraulic oil Figures 2, 4 and 5 schematically show the heat exchanger comprises an oil radiator 5, a coolant radiator 27 and a heat exchanger attachment 39, wherein the heat exchanger attachment 39 encapsulating the oil radiator 5 and the coolant radiator 27 as a single unit through a housing 39.1; the oil radiator 5 comprises of an oil inlet chamber 5.1, an oil outlet chamber 5.2, a first spacer 5.3, an oil radiator inlet 5.4, an oil radiator outlet 5.5 and a number of heat dissipation oil pipes 5.6; the coolant radiator 27 comprises a water inlet chamber 27.1, an water outlet chamber 27.2, a second spacer 27.3, a coolant radiator inlet 27.4, a coolant radiator outlet 27.5, a number of heat dissipation water pipes 27.6 and an expansion pipe inlet 27.7; the heat exchanger attachment 39 comprises a housing 39.1, a radiator core 39.2, a pressure plate 39.3 and a screw 39.4. The cross-sectional shape of heat dissipation oil pipes 5.6 and heat dissipation water pipes 27.6 are both rectangular and heat dissipation oil pipes 5.6 and heat dissipation water pipes 27.6 are staggered and there is a section of heat dissipation water pipes 27.6 between two adjacent sections of heat dissipation oil pipes 5.6, and the adjacent pipes are separated by radiator core 39.2, and all heat dissipation oil pipes 5.6 are connected. The heat dissipation oil pipe 5.6 and the heat dissipation water pipe 27.6 are capable of heat exchange to achieve the purpose of a weak demand heat dissipation system for power electronic components to assist the strong demand cooling system for hydraulic oil; oil inlet chamber 5.1 and oil outlet chamber 5.2 are separated by first partition 5.3, oil radiator inlet 5.4 is opened above oil inlet chamber 5.1, oil inlet chamber 5.1 is in communication with heat dissipation oil pipes 5.6 inlet, oil outlet chamber 5.2 is opened with oil radiator outlet 5.5 above oil outlet chamber 5.2. The oil outlet chamber 5.2 is in communication with the outlet of heat dissipation oil pipes 5.6 (near the oil radiator outlet 5.5); The water inlet chamber 27.1 and the water outlet chamber 27.2 are separated by a second partition 27.3, and a coolant radiator inlet 27.4 is opened above the water inlet chamber 27.1, which is in communication with the inlet of the heat dissipation water pipes 27.6 (near the coolant radiator inlet 27.4), and a coolant radiator outlet 27.5 is opened above the water outlet chamber 27.2, which is in communication with the outlet of the heat dissipation water pipes 27.6 (near the coolant radiator outlet 27.5). Particularly, an expansion pipe inlet 27.7 is opened above the water inlet chamber 27.1, and the expansion pipe inlet 27.7 is in communication with the inlet of the expansion tank 30 via a water pipe. Half of the housing 39.1 of the heat exchanger attachment 39 is set into the reinforced outer wall of the intelligent underwater bulldozer and is fixedly mounted to the reinforced outer wall by means of a pressure plate 393 welded to the housing 39.1 and screws 39.4; the radiator core 39.2 is fixed to the housing 39.1; the heat exchanger achieves the following functions: firstly, the heat dissipation oil pipes 5.6 and the heat dissipation water pipes 27.6 exchange heat through the radiator core 39.2, and secondly, the heat dissipation oil pipes 5.6 and the heat dissipation water pipes 27.6 exchange heat from the coolant and hydraulic oil with the external water environment intelligently through the radiator core 39.2.

Referring to FIG. 2, the oil radiator outlet 5.5 is in communication with the third inlet 9.3 of the hydraulic oil tank 9 through an oil pipe, on which the first check valve 8 is Installed to prevent the first centrifugal pump 3 from backflowing when the oil is not working. The channel makes the cooled fluids flow back to the hydraulic fluid tank 9 to complete a working cycle. Hydraulic oil cooling system is a set of independent cooling system, and its characteristics are as follows: firstly, cooling from the root of the fluid to lower the temperature of the hydraulic system, and it has nothing to do with the working state of the hydraulic subsystem, and the working state of the hydraulic subsystem will not affect dissipation effect of the hydraulic system; secondly, the pipes of the hydraulic subsystem can be designed to be shorter, with less resistance, reducing the delay and damage of mechanical parts.

Referring to FIG. 2 and FIG. 3, the detection unit comprises a first oil temperature sensor 6, a second oil temperature sensor 7, a third oil temperature sensor 13, a fourth oil temperature sensor 19 and a first flow meter 4; The first oil temperature sensor 6, the second oil temperature sensor 7, the third oil temperature sensor 13, the fourth oil temperature sensor 19 and the first flow meter 4 all transmit information with the electronic control unit; the first oil temperature sensor 6 is installed between the first oil outlet 9.5 and the second oil outlet 9.6 and fixed to the tank body 9. the first oil temperature sensor 6 directly detects the oil temperature of the first hydraulic subsystem (hydraulic cylinder 15 subsystem) and the second hydraulic subsystem (bidirectional variable hydraulic motor 21 subsystem). The second oil temperature sensor 7 is installed in the oil pipe between the third oil inlet 9.3 and the oil radiator 5 for detecting the heat dissipation effect of the oil radiator 5; The third oil temperature sensor 13 is installed at the oil outlet of the second centrifugal pump 12 to detect the oil temperature after the work of the second centrifugal pump 12; The fourth oil temperature sensor 19 is installed at the oil outlet of the third centrifugal pump 18 to detect the oil temperature after the work of the third centrifugal pump 18; the first flow meter 4 is installed at the oil outlet of the first centrifugal pump 3, and the first flow meter 4 is fixed to the housing of the first centrifugal pump 3 to dynamically detect the instantaneous flow of the first centrifugal pump 3 and transmit the detection signal to the electronic control unit.

Referring to FIG. 2, the first hydraulic subsystem comprises a second oil pump motor 10, a second motor controller 11, a second centrifugal pump 12, a third oil temperature sensor 13, a first reversing valve 14 and a hydraulic cylinder 15; the second centrifugal pump 12 is in communication with the hydraulic cylinder 15 through the first reversing valve 14, and the second centrifugal pump 12 is keyed to the second oil pump motor 10, and the second oil pump motor 10 is controlled by the second motor controller 11, the second motor controller 11 and electronic control unit exchange information; the second hydraulic subsystem comprises a third oil pump motor 16, a third motor controller 17, a third centrifugal pump 18, a fourth oil temperature sensor 19, a second reversing valve 20 and a bidirectional variable hydraulic motor 21, and the third centrifugal pump 18 is connected to the bidirectional variable hydraulic motor 21 through the second reversing valve 20, and the third centrifugal pump 18 is keyed to the third oil pump motor 16, and the third oil pump motor 16 is controlled by the third motor controller 17, which transmits signals to the electronic control unit; the hydraulic cylinder 15 and the bidirectional variable hydraulic motor 21 are the main actuating elements of the hydraulic system of the intelligent underwater bulldozer, and the first reversing valve 14 and the second reversing valve 20 are the main control elements of the hydraulic system of the intelligent underwater bulldozer; the electronic control unit can control its direction The hydraulic oil in the hydraulic oil tank 9 is pressurized by the second centrifugal pump 12 and enters the hydraulic cylinder 15 through the first hydraulic subsystem distribution valve 22 and the first reversing valve 14 in turn, and after pushing the piston, the hydraulic oil flows through the outlet of the second reversing valve 14 and returns to the hydraulic oil tank 9; the hydraulic oil in the hydraulic oil tank 9 is pressurized by the third centrifugal pump 18 and enters the bidirectional variable hydraulic motor 21 through the second hydraulic subsystem distribution valve 23 and the second reversing valve 20 in turn. The hydraulic oil in hydraulic oil tank 9, under the pressure of the third centrifugal pump 18, enters the bidirectional variable hydraulic motor 21 through the second hydraulic subsystem distribution valve 23 and the second reversing valve 20, and the hydraulic oil drives the sprocket installed coaxially with the bidirectional variable hydraulic motor 21, where the first hydraulic subsystem distribution valve 22 and the second hydraulic subsystem distribution valve 23, under the control of the electronic control unit, distribute the pressure of the hydraulic oil reasonably to the multiple groups of mechanical arms and sprockets, ensuring that the intelligent underwater bulldozer completes the complex underwater operations.

Referring to FIG. 2, power electronic component cooling system comprises a water pump motor 24, a fourth motor controller 25, a fourth centrifugal pump 26, a coolant radiator 27, a flow control valve 28, a second flow meter 29, an expansion tank 30, a first water temperature sensor 31, a second water temperature sensor 32, a third water temperature sensor 33, a second check valve 34, a third check valve 35 and components to be cooled; components to be cooled consist of motor controller, battery pack 36, variable voltage rectification module and power supply power distribution module 38; the inlet of the fourth centrifugal pump 26 is in communication with the coolant radiator outlet 27.5 through a pipe, where the third water temperature sensor 33 is opened; the fourth centrifugal pump 26 is keyed to the water pump motor 24, which is controlled by the fourth motor controller 25, and the fourth motor controller 25 in signal transmission with electronic control unit for signal transmission; the expansion pipe inlet 27.7 of the coolant radiator 27 is in communication with the expansion tank 30; the power electronic component cooling system is divided into two parallel water paths, the first parallel water path flowing through the order of the fourth centrifugal pump 26, battery pack 36, variable voltage rectification module 37, power supply power distribution module 38, coolant radiator 27 and the fourth centrifugal pump 26, and the second parallel water path flowing through the order of the fourth centrifugal pump 26, fourth motor controller 25 and pump motor 24, third oil pump motor 16 and third motor controller 17, second oil pump motor 10 and second motor controller I I, first oil pump motor I and first motor controller 2, coolant radiator 27, and fourth centrifugal pump 26. Particularly, a rubber ring (not shown in the drawings) is required to seal the waterway interface. The arrangement of the water path between the power electronics components to be cooled is prior technique and will not be repeated in the present invention. The fourth centrifugal pump 26 provides power for the flow of coolant, and a second flow meter 29 is installed in the cooling line between the fourth centrifugal pump 26 and the battery pack 36 for detecting the instantaneous flow rate of the fourth centrifugal pump 26 at all times and transmitting it to the electronic control unit; near the convergence of the first parallel water path and the second parallel water path, a first water temperature sensor 31 is installed on the second parallel water path for detecting the temperature of the coolant after cooling the power electronic components flowing through the second parallel water path, and the second water temperature sensor 32 is installed on the main waterway after the convergence of the two parallel water paths for detecting the temperature of the coolant after flowing through all electronic components; near the convergence of the first parallel water path and the second parallel water path, a third check valve 35 is also installed on the second parallel water path for preventing the backflow of oil when the fourth centrifugal pump 26 is not working; the third water temperature sensor 33 is installed on the pipe between the coolant radiator 27 and the fourth centrifugal pump 26, and is fixedly installed on the housing of the fourth centrifugal pump 26 for detecting the coolant temperature after passing through the coolant radiator 27; The electronic control unit determines the cooling demand of the cooling system of power electronic components based on the water temperature information of the first water temperature sensor 31 and the second water temperature sensor 32, detects the working effect of the coolant radiator 27 based on the water temperature information measured by the third water temperature sensor 33, and thus controls the instantaneous flow rate of the fourth centrifugal pump 26 through the fourth motor controller 25 to adjust the coolant flow rate so as to adapt to the cooling demand.

FIG. 6 shows a flow control valve 28 is installed at the inlet of the second parallel water path to adaptively control the flow of the second parallel water path according to the coolant temperature; the flow control valve 28 comprises a thermosensitive material 28.1, a valve body 28.2, a preload spring 28.3, a valve seat 28.4, a first guide block 28.5, a flow control valve inlet 28.6 and a flow control valve outlet 28.7; the flow control valve 28 is provided with a thermosensitive material 28.1 on one side of the housing, and the thermosensitive material 28.1 is in contact with the front end of the valve body 28.2, and the front end of the valve body 28.2 is supported by a first guide block 28.5, and the rear end of the valve body 28.2 is movably connected to the valve seat 28.4, and the end of the valve body 28.2 is supported by a second guide block (not shown in the figure), and the rear end of the valve body 28.2 is also fixed to the flow control valve 28 housing by a preload spring 28.3; in the initial state, the preload force of the preload spring 28.3 tightens the valve body 28.2 against the valve seat 28.4, when coolant flows in from flow control valve inlet 28.6, heat is transferred along the valve body 28.2 to the thermosensitive material 28.1, and the deformation of heat thermosensitive material 28.1 is positively correlated with the coolant temperature; after the coolant temperature is raised, the heat thermosensitive material 28.1 pushes the valve body 28.2 to overcome the preload spring 28.3, and the valve port is then opened and the coolant passes through the valve port and flows out of the flow control valve outlet 28.7; when the cooling demand is small, the flow control valve 28 controls the flow of coolant through the second parallel water path by reducing the valve port opening, thus enhancing the cooling effect of the first parallel cooling path while the flow of coolant in the main waterway remains unchanged.

Referring to FIG. 2, the expansion tank 30 has a water inlet and outlet, the expansion tank inlet is in communication with the expansion pipe inlet 27.7 of the coolant radiator 27 through a water pipe, which is used to introduce water vapor bubbles in the coolant radiator 27 into the expansion tank 30. There are two functions: one of which can depressurize the cooling water path, and the other prevents the impeller of the fourth centrifugal pump 26 from cavitation due to water vapor bubbles; the expansion tank 30 outlet is in communication with the main waterway of the power electronic component cooling system, and is used to automatically adjust the volume of coolant involved in the cooling cycle according to the water level information of the expansion tank 30, and the water level control valve (not shown in the figure) plays a role in stabilizing the pressure of the power electronic component cooling system; a second check valve 34 is installed on the pipe connecting the water outlet of the expansion tank 30 to the trunk path of the cooling system of the power electronic components to prevent backflow of coolant when the expansion tank 30 is not working.

The working process of the dual cooling system of an intelligent underwater bulldozer is as follows: In the proposed hydraulic oil cooling system, the hydraulic oil from the hydraulic oil tank 9 is pressurized by the second centrifugal pump 18 and the third centrifugal pump 12 respectively, so the hydraulic cylinder 15 and the two-way variable hydraulic motor 21 work to convert the fluid pressure energy and kinetic energy into the mechanical energy required for the movement of the bulldozer and the sprocket. In this process, the heat generated by the operation is absorbed by the hydraulic oil and flows through the two oil outlets of the first reversing valve 14 and the two oil outlets of the second reversing valve 20, respectively, and returns to the hydraulic oil tank 9. When the first oil temperature sensor 6 detects that the oil extraction temperature of the first hydraulic subsystem or the second hydraulic subsystem exceeds the preset normal threshold value of 60 °C, or the oil temperature of the second centrifugal pump 12 after doing work exceeds the threshold value of 85 °C, or the oil temperature of the third centrifugal pump 18 after doing work exceeds the threshold value of 70 °C, the hydraulic oil cooling system starts to work, and the first motor controller 2 controls the first oil pump motor 1 to drive the first centrifugal pump 3 to suck the hydraulic oil to be cooled in the hydraulic oil tank 9 from the third outlet 9.7 of the oil tank, so the hydraulic oil can be pumped to the oil radiator 5 for heat dissipation. Because the oil radiator 5 and coolant radiator 27 encapsulated as a whole, heat dissipation oil pipe 5.6 and heat dissipation pipe 27.6 staggered arrangement, heat exchange not only happen between the hydraulic oil and the external water environment, but also happen between the hydraulic oil and the coolant through the radiator core 39.2, to achieve that the weak demand cooling system of power electronic components assist the strong demand cooling system of hydraulic oil. The cooled hydraulic oil flows back into the hydraulic oil tank 9 through the oil radiator outlet 5.5 and the first inlet 9.1 of the oil tank, completing a working cycle; meanwhile, the electronic control unit determines the cooling demand of the hydraulic oil cooling system at the current moment based on the hydraulic oil temperature signals detected by the first oil temperature sensor 6 and the second oil temperature sensor 7, compared with the Map of hydraulic oil cooling demand, to adaptively adjust the pump oil pressure of the first centrifugal pump 3, so that the instantaneous flow of hydraulic oil in the pipes approaches the target flow to meet the heat dissipation demand.

In the power electronic component cooling system, the heat generated by the operation of the power electronic components heats the coolant, and when the electronic control unit determines the cooling demand of the cooling system of the power electronic components based on the coolant temperature detected by the first water temperature sensor 31 and the second water temperature sensor 32, comparing with the Map of cooling demand, when the temperature of the second parallel water path detected by the first water temperature sensor 31 is higher than 40 °C, or the temperature of the second parallel water path detected by the second water temperature sensor 32 is higher than 45 °C, the power electronic component cooling system starts working, and the fourth motor controller 25 adaptively adjusts the pump oil pressure of the fourth centrifugal pump 26 and adaptively adjusts the coolant flow rate in the pipes according to the electrical signal of heat dissipation demand. Referring to FIG. I, the coolant water path is divided into a first parallel water path and a second parallel water path, where the first parallel water path flows sequentially through the fourth centrifugal pump 26, the battery pack 36, the variable voltage rectification module 37, and the power supply power distribution module 38 into the coolant radiator 27, and the second parallel water path flows sequentially through the four motor controllers into the coolant radiator 27; Because of the staggered arrangement of the heat dissipation oil pipe 5.6 and the cooling water pipe 27.6, when the coolant exchanges heat with the external water environment, the coolant water circuit simultaneously assists the hydraulic oil to dissipate heat and improves the comprehensive heat dissipation capacity of the intelligent underwater bulldozer; the cooled coolant flows back to the fourth centrifugal pump 26 through the coolant radiator outlet 27.5 to complete a working cycle; in this cooling process, the electronic control unit adaptively controls the flow rate of the second parallel water path according to the coolant temperature of the second parallel water path; in this process, the expansion tank 30 is able to introduce water vapor bubbles from the coolant radiator 27 into the expansion tank 30 to depressurize the cooling water circuit, and to prevent the impeller of the fourth centrifugal pump 26 from cavitation due to the water vapor bubbles.

The described embodiments are the preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any obvious improvements, or variations without departing from the substance of the present invention fall within the scope of protection of the present invention.

Claims

Claims What is claimed is: 1. A cooling system of an intelligent underwater bulldozer, characterized by comprising a hydraulic oil cooling system and a power electronic component cooling system; wherein the hydraulic oil cooling system comprises a hydraulic oil tank (9), a power unit, a detection unit and a heat exchanger; the hydraulic oil tank (9) is in communication with a hydraulic cylinder (15) through a second centrifugal pump (12), and the hydraulic oil tank (9) is also in communication with a bidirectional variable hydraulic motor (21) through a third centrifugal pump (18); the power unit comprises a first oil pump motor (I), a first motor controller (2), and a first centrifugal pump (3), wherein the first oil pump motor (I) is in signal transmission with the first motor controller (2), and the first motor controller (2) is in signal transmission with an electronic control unit, and the first oil pump motor (1) is connected to the first centrifugal pump (3), and an oil inlet of the first centrifugal pump (3) is in communication with a third outlet port (9.7) of the hydraulic oil tank (9), and an oil outlet of the first centrifugal pump (3) is in communication with an oil radiator inlet (5.4); the detection unit comprises a first oil temperature sensor (6) and a second oil temperature sensor (7), wherein the first oil temperature sensor (6) is installed between a first oil outlet (9.5) and a second oil outlet (9.6), and the second oil temperature sensor (7) is installed on an oil pipe between a third oil inlet (9.3) and an oil radiator (5); the heat exchanger comprises an oil radiator (5) and a coolant radiator (27), wherein the oil radiator (5) and the coolant radiator (27) are encapsulated as a unit; the oil radiator (5) comprises an oil inlet chamber (5.1), an oil outlet chamber (5.2), a first partition (5.3), an oil radiator inlet (5.4), an oil radiator outlet (5.5), and a number of heat dissipation oil pipes (5.6), wherein the oil inlet chamber (5.1) and the oil outlet chamber (5.2) are separated by the first partition (5.3), and the oil radiator inlet (5.4) is provided above the oil inlet chamber (5.1), and the oil inlet chamber (5.1) is in communication with an inlet of each of the heat dissipation oil pipes (5.6), and the oil radiator outlet (5.5) is provided above the oil outlet chamber (5.2), and the oil outlet chamber (5.2) is in communication with an outlet of each of the heat dissipation oil pipes (5.6); the coolant radiator (27) comprises a water inlet chamber (27.1), a water outlet chamber (27.2), a second partition (27.3), a coolant radiator inlet (27.4), a coolant radiator outlet (27.5), a number of heat dissipation water pipes (27.6), and an expansion pipe inlet (27.7), wherein the water inlet chamber (27.1) and the water outlet chamber (27.2) are separated by the second partition (27.3), and the coolant radiator inlet (27.4) is provided above the water inlet chamber (27.1), and the water inlet chamber (27.1) is in communication with an inlet of each of the heat dissipation water pipes (27.6), the coolant radiator outlet (27.5) is provided above the water outlet chamber (27.2), and the water outlet chamber (27.2) is in communication with an outlet of each of the heat dissipation water pipes (27.6), and the expansion pipe inlet (27.7) is provided above the water inlet chamber (27.1), and the expansion pipe inlet (27.7) is in communication with a water inlet of an expansion tank (30); the heat dissipation oil pipes (5.6) and the heat dissipation water pipes (27.6) are staggered, and the number of the heat dissipation oil pipes (5.6) are in communication with each other, and the number of the heat dissipation water pipes (27.6) are in communication with each other; heat dissipation oil pipes (5.6) and heat dissipation water pipes (27.6) which are adjacent to each other are separated by a radiator core (39.2); the power electronic component cooling system comprises a water pump motor (24), a fourth motor controller (25), a fourth centrifugal pump (26), a second flow meter (29), the expansion tank (30), a first water temperature sensor (31), a second water temperature sensor (32), and a third water temperature sensor (33); a water inlet of the fourth centrifugal pump (26) is in communication with the coolant radiator outlet (27.5), and the third water temperature sensor (33) is installed on the pipe between the fourth centrifugal pump (26) and the coolant radiator outlet (27.5), and the fourth centrifugal pump (26) is connected to the water pump motor (24), the water pump motor (24) is controlled by the fourth motor controller (25), the fourth motor controller (25) transmits signals to the electronic control unit; the power electronic component cooling system is divided into two parallel water paths comprising a first parallel water path and a second parallel water path, wherein the first parallel water path flows through in sequence the fourth centrifugal pump (26), a battery pack (36), a variable voltage rectifier module (37), a power supply power distribution module (38), the coolant radiator (27), and the fourth centrifugal pump (26), and the second parallel water path flows through in sequence the fourth centrifugal pump (26), the fourth motor controller (25), and the water pump motor (24), a third oil pump motor (16) and a third motor controller (17), a second oil pump motor (10) and a second motor controller (11), the first oil pump motor (1) and the first motor controller (2), the coolant radiator (27), and the fourth centrifugal pump (26); near a convergence of the first parallel water path and the second parallel water path, the first water temperature sensor (31) is installed on the second parallel water path, and the second water temperature sensor (32) is installed on a main waterway after the convergence of the first parallel water path and the second parallel water path; the second flow meter (29) is installed in a pipeline between the fourth centrifugal pump (26) and the battery pack (36).
2. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed dissipative oil pipe (5.6) and the heat dissipation water pipes (27.6) both have a rectangular cross-sectional shape.
3. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed connected dissipative oil pipes (5.6) and the proposed connected heat dissipation water pipes (27.6) both are bow shape.
4. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed oil radiator (5) and coolant radiator (27) are encapsulated as a single unit by means of a housing (39.1) of a heat exchanger attachment (39), and the proposed housing (39.1) being fixedly mounted on a reinforced outer wall of the intelligent underwater bulldozer by means of a pressure plate (39.3) and screws (39.4).
5. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed the oil radiator outlet (5.5) is fitted with a first check valve on the pipe connected to the third oil inlet (9.3).
6. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed detection unit further comprises a third oil temperature sensor (13), a fourth oil temperature sensor (19) and a first flow meter (4), wherein the proposed third oil temperature sensor (13) is mounted at the outlet of the second centrifugal pump (12), and the proposed fourth oil temperature sensor (19) is mounted at the outlet of the third centrifugal pump (18), and the proposed first flow meter (4) is installed at the oil outlet of the first centrifugal pump (3).
7. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that the proposed flow control valve (28) is installed at the inlet of the second parallel water path, and the proposed flow control valve (28) comprises a thermosensitive material (28.1), a valve body (28.2), a preload spring (28.3), a valve seat (28.4), a first guide block (28.5), a flow control valve inlet ( 28.6) and flow control valve outlet (28.7), wherein the flow control valve (28) is provided with thermal material (28.1) on one side of the housing, and the thermal material (28.1) is in contact with the front end of the valve body (28.2), and the front end of the valve body (28.2) is supported by the first guide block (28.5), and the rear end of the valve body (28.2) is movably connected to the valve seat (28.4), and the end of the valve body (28.2) is supported by a second guide block and the rear end of the valve body (28.2) is also fixed to the flow control valve (28) housing by a preload spring (28.3).
8. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that a third check valve (35) is installed on the proposed second parallel water path.
9. The cooling system of the intelligent underwater bulldozer according to claim 1, characterized in that a second check valve (34) is installed on the pipe of connecting the proposed expansion tank (30) and the main waterway of power electronic component cooling system.
10. An intelligent underwater bulldozer, characterized by comprising the cooling system according to any one of claims 1-9.