CN111336138A

CN111336138A - Hydraulic pressure opens and stops device

Info

Publication number: CN111336138A
Application number: CN202010221551.6A
Authority: CN
Inventors: 韩慧仙; 陶东波; 舒常平
Original assignee: Hunan Mechanical and Electrical Polytechnic
Current assignee: Hunan Mechanical and Electrical Polytechnic
Priority date: 2020-03-26
Filing date: 2020-03-26
Publication date: 2020-06-26
Anticipated expiration: 2040-03-26
Also published as: CN111336138B

Abstract

The invention discloses a hydraulic start-stop device, which comprises a prime power system, a first hydraulic system, a second hydraulic system and an electric control system, wherein the prime power system comprises an engine and is used for providing energy; the first hydraulic system is used for transferring and converting energy provided by the prime power system, and outputting energy for external work to complete the expected action or function of the equipment; the second hydraulic system is used for absorbing and storing energy of the prime power system and assisting the prime power system to drive through the stored energy; the electric control system is used for detecting state parameters of the prime power system, the first hydraulic system and the second hydraulic system; and if the working devices driven by the first hydraulic system and the second hydraulic system do not act and do not receive the operation instruction, closing the engine. The hydraulic starting and stopping device provided by the invention has the advantages of less additional elements and small occupied space; the model selection specification of the engine can be reduced, and the total cost of the working machine is reduced; the oil consumption, the emission and the noise of the prime motor are reduced.

Description

Hydraulic pressure opens and stops device

Technical Field

The invention relates to the field of power system control, and particularly discloses a hydraulic start-stop device.

Background

The working machine includes an engineering machine, an agricultural machine, a mining machine, a sanitation machine, an engineering vehicle, an industrial equipment, and the like. Among them, the power system of the working machine is divided into two types: one is energy provided by using environment, such as commercial power; another type is a prime mover that is carried on its own using a work machine, such as an internal combustion engine, electric motor, or the like.

For a working machine carrying an internal combustion engine by itself, there is generally a problem of energy consumption of the internal combustion engine during design and use, especially in a low power output state.

In the prior art, the energy consumption of the internal combustion engine is generally reduced by manually adjusting the rotating speed of the internal combustion engine (namely, when the engine idles, a driver adjusts the rotating speed of the engine to be low, the rotating speed of the engine is reduced, and the oil consumption is naturally reduced), but the energy consumption is manually operated in actual use, and the operating intensity of the driver is increased; in the prior art, a method for automatically reducing the rotation speed of the internal combustion engine by using a controller of the working machine is also available, but the rotation speed and the oil consumption of the internal combustion engine are only reduced from a higher level to a second higher level, for example, an automatic idle speed control technology of the engine is provided, and the control method of the technology is as follows: when the engine is at a high rotating speed, all working devices do not work outwards, and the time lasts to a preset value, the controller automatically reduces the rotating speed of the engine to an idling state, so that the oil consumption, the emission and the noise of the engine are reduced. However, the problem is that the engine also has a certain fuel consumption in the idle state, which is not valuable, is completely wasteful, and has emissions and noise.

Therefore, the engine of the existing working machine still has oil consumption, emission and noise under the idling state, and is a technical problem to be solved urgently.

Disclosure of Invention

The invention provides a hydraulic start-stop device, aiming at solving the technical problems of oil consumption, emission and noise of an engine of the existing operation machinery under the idling condition.

The invention provides a hydraulic start-stop device, which comprises a prime power system, a first hydraulic system, a second hydraulic system and an electric control system, wherein,

a prime mover system including an engine for providing a source of energy;

the first hydraulic system is connected with the prime power system and is used for transferring and converting energy provided by the prime power system, and outputting energy for external work to complete the expected action or function of the equipment;

the second hydraulic system is connected with the prime power system and used for absorbing and storing energy of the prime power system and assisting the prime power system to drive through the stored energy;

the electric control system is respectively connected with the prime power system, the first hydraulic system and the second hydraulic system and is used for detecting state parameters of the prime power system, the first hydraulic system and the second hydraulic system; and if the working devices driven by the first hydraulic system and the second hydraulic system do not act and do not receive the operation instruction, closing the engine.

Further, the electric control system comprises a rotating speed detection device, a torque detection device, a pressure sensor and a controller, the first hydraulic system comprises a reversing valve, a one-way valve, a first overflow valve and a second overflow valve, the second hydraulic system comprises a hydraulic pump motor and an energy accumulator, wherein,

the rotating speed detection device is connected with the engine and used for detecting the rotating speed of the engine;

the torque detection device is connected with the engine and used for detecting the torque of the engine;

the oil suction port of the hydraulic pump motor is divided into two paths, one path is connected with the one-way valve, and the other path is connected with the energy accumulator through the oil outlet of the reversing valve; the oil pressing port of the hydraulic pump motor is divided into two paths, one path is connected with the first overflow valve, and the other path is connected with the energy accumulator through the oil inlet of the reversing valve; the hydraulic pump motor is used for absorbing the power of the engine or assisting the engine to work;

an oil inlet of the second overflow valve is connected with the energy accumulator; a pressure sensor for detecting an accumulator pressure;

the controller is respectively electrically connected with the engine, the rotating speed detection device, the torque detection device, the reversing valve and the first overflow valve and is used for acquiring the working state of the engine according to the rotating speed and the torque of the engine detected by the rotating speed detection device and the torque detection device; monitoring the power stored in the energy accumulator according to the pressure of the energy accumulator detected by the pressure sensor, and controlling the reversing valve to automatically start the engine by the power stored in the energy accumulator if the engine needs to be started; and if the engine is in a light load working condition, controlling the hydraulic pump motor to charge the accumulator.

Further, the controller comprises a rotation speed control module,

the rotating speed control module is used for processing an engine rotating speed signal n detected by the rotating speed detection device and judging whether to start liquid filling or not, and if so, filling liquid into the energy accumulator; if not, the accumulator is filled with liquid.

Furthermore, the rotating speed control module comprises a first preset unit, a first comparison unit and a first judgment unit,

the first preset unit is used for presetting an energy accumulator pressure threshold value n 1;

the first comparison unit is used for comparing the engine speed signal n detected by the speed detection device with a preset accumulator pressure threshold value n 1;

the first judgment unit is used for judging that liquid filling needs to be started if the engine speed signal n is greater than the accumulator pressure threshold value n1, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to act, and controlling the hydraulic pump motor to fill liquid into the accumulator; and if the engine speed signal n is less than or equal to the accumulator pressure threshold n1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to stop acting, and controlling the hydraulic pump motor to finish filling the liquid into the accumulator.

Further, the rotating speed control module comprises a first calculating unit, a second preset unit, a second comparing unit and a second judging unit,

the first calculating unit is used for obtaining the derivative of the rotating speed signal n of the engine detected by the rotating speed detecting device and calculating the engine rotating speed change rate n' of the rotating speed signal n of the engine along with the change of time;

the second preset unit is used for presetting an engine rotating speed change rate threshold value n' 1 in advance;

the second comparison unit is used for comparing the calculated engine speed change rate n 'with a preset engine speed change rate threshold value n' 1;

the second judgment unit is used for judging that liquid filling needs to be started if the engine speed change rate n 'is greater than the engine speed change rate threshold value n' 1, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to act, and controlling the hydraulic pump motor to fill liquid into the energy accumulator; and if the engine speed change rate n 'is less than or equal to the engine speed change rate threshold n' 1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to stop acting, and controlling the hydraulic pump motor to finish filling liquid to the energy accumulator.

Further, the controller includes a torque control module,

the torque control module is used for processing the engine torque signal T detected by the torque detection device and judging whether to start liquid filling or not, and if so, filling liquid into the energy accumulator; if not, the accumulator is filled with liquid.

Further, the torque control module comprises a third preset unit, a third comparison unit and a third judgment unit,

the third preset unit is used for presetting an engine torque threshold value T1;

the third comparison unit is used for comparing the engine torque signal T detected by the torque detection device with a preset engine torque threshold value T1;

the third judgment unit is used for judging that liquid filling needs to be started if the engine torque signal T is larger than the engine torque threshold T1, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to act, and controlling the hydraulic pump motor to fill liquid into the energy accumulator; and if the engine torque signal T is smaller than or equal to the engine torque threshold T1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to stop acting, and controlling the hydraulic pump motor to finish filling the liquid to the accumulator.

Further, the torque control module comprises a second calculating unit, a fourth presetting unit, a fourth comparing unit and a fourth judging unit,

the second calculating unit is used for obtaining the derivative of the engine torque signal T of the engine detected by the torque detecting device and obtaining the engine torque change rate n' of the engine torque signal T of the engine changing along with time;

the fourth presetting unit is used for presetting an engine torque change rate threshold value n' 1;

the fourth comparison unit is used for comparing the obtained engine torque change rate n 'with a preset engine torque change rate threshold value n' 1;

the fourth judgment unit is used for judging that liquid filling needs to be started if the engine torque change rate n 'is greater than the engine torque change rate threshold value n' 1, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to act, and controlling the hydraulic pump motor to fill liquid into the energy accumulator; and if the engine torque change rate n 'is less than or equal to the engine torque change rate threshold n' 1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to stop acting, and controlling the hydraulic pump motor to finish filling liquid to the energy accumulator.

Further, the controller includes a pressure control module,

the pressure control module is used for processing an energy accumulator pressure signal P of the energy accumulator detected by the pressure sensor, judging whether to start liquid filling or not, and if so, filling liquid into the energy accumulator; if not, the accumulator is filled with liquid.

Further, the pressure control module comprises a fifth preset unit, a fifth comparison unit and a fifth judgment unit,

the fifth preset unit is used for presetting an energy accumulator pressure threshold value P1;

the fifth comparison unit is used for comparing the accumulator pressure signal P of the accumulator detected by the pressure sensor with a preset accumulator pressure threshold value P1;

the fifth judgment unit is used for judging that liquid filling needs to be started if the accumulator pressure signal P is larger than the accumulator pressure threshold value P1, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to act, and controlling the hydraulic pump motor to fill liquid into the accumulator; and if the accumulator pressure signal P is smaller than or equal to the accumulator pressure threshold P1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system and the second hydraulic system, controlling the reversing valve and the first overflow valve to stop acting, and controlling the hydraulic pump motor to finish filling the liquid into the accumulator.

The beneficial effects obtained by the invention are as follows:

the invention provides a hydraulic start-stop device, which adopts a prime power system, a first hydraulic system, a second hydraulic system and an electric control system, and closes an engine when all working devices do not act and a driver has no operation instruction; when the controller considers that the engine needs to be started, the engine is automatically started through the power stored by the energy accumulator; when the engine is in a light load condition, the accumulator is charged. The hydraulic starting and stopping device provided by the invention has the advantages of less additional elements and small occupied space; the model selection specification of the engine can be reduced, and the total cost of the working machine is reduced; the oil consumption, the emission and the noise of the prime motor are reduced.

Drawings

FIG. 1 is a functional block diagram of an embodiment of a hydraulic start-stop device provided by the invention;

FIG. 2 is a schematic connection diagram of an embodiment of a hydraulic hybrid power unit provided in the present invention;

FIG. 3 is a functional block diagram of a first embodiment of the controller shown in FIG. 2;

FIG. 4 is a functional block diagram of a first embodiment of a speed control module shown in FIG. 3;

FIG. 5 is a functional block diagram of a second embodiment of the speed control module shown in FIG. 3;

FIG. 6 is a functional block diagram of a first embodiment of the torque control module shown in FIG. 3;

FIG. 7 is a functional block diagram of a second embodiment of the torque control module shown in FIG. 3;

FIG. 8 is a functional block diagram of an embodiment of the pressure control module shown in FIG. 3.

The reference numbers illustrate:

100. a prime mover system; 200. a first hydraulic system; 300. a second hydraulic system; 400. an electrical control system; 10. an engine; 20. a rotational speed detection device; 30. a torque detection device; 40. a diverter valve; 50. a one-way valve; 60. a first overflow valve; 70. a second overflow valve; 80. an accumulator; 90. a pressure sensor; 110. a controller; 120. a hydraulic pump motor; 111. a rotation speed control module; 1111. a first preset unit; 1112. a first comparing unit; 1113. a first judgment unit; 1114. a first calculation unit; 1115. a second preset unit; 1116. a second comparing unit; 1117. a second judgment unit; 112. a torque control module; 1121. a third preset unit; 1122. a third comparing unit; 1123. a third judgment unit; 1124. a second calculation unit; 1125. a fourth preset unit; 1126. a fourth comparing unit; 1127. a fourth judgment unit; 113. a pressure control module; 1131. a fifth preset unit; 1132. a fifth comparing unit; 1133. and a fifth judging unit.

Detailed Description

In order to better understand the technical solution, the technical solution will be described in detail with reference to the drawings and the specific embodiments.

As shown in fig. 1, a first embodiment of the present invention provides a hydraulic start-stop device, which includes a prime mover system 100, a first hydraulic system 200, a second hydraulic system 300, and an electrical control system 400, wherein the prime mover system 100 includes an engine 10 for providing energy; the first hydraulic system 200 is connected with the prime power system 100, and is used for transferring and converting energy provided by the prime power system 100, outputting energy for external work and completing the expected action or function of equipment; the second hydraulic system 300 is connected with the motive power system 100 and is used for absorbing and storing energy of the motive power system 100 and assisting the motive power system 100 to drive through the stored energy; the electrical control system 400 is respectively connected with the prime power system 100, the first hydraulic system 200 and the second hydraulic system 300, and is used for detecting state parameters of the prime power system 100, the first hydraulic system 200 and the second hydraulic system 300; if the working devices driven by the first hydraulic system 200 and the second hydraulic system 300 are not operated and no operation command is received, the engine 10 is shut down.

In the present embodiment, prime mover system 100 includes an engine 10 and a transfer case. The original engine 10 provides energy for the entire system. The function of the transfer device is to transfer the power output by the prime mover to different power components, respectively. Types of transfer devices include through drive shafts, transfer cases, or other forms of power splitting mechanisms.

The first hydraulic system 200 is connected to the prime mover system 100, and is used for transferring and converting energy of the prime mover, outputting energy for external work, and completing the desired action or function of the equipment. The first hydraulic system 200 includes a hydraulic power component, a hydraulic adjustment component, a hydraulic actuation component, and a hydraulic assist component. The function of the hydraulic power component is to absorb the energy output by the prime mover and convert the energy form into hydraulic energy to be output to other hydraulic components. Types of hydraulic power components include hydraulic pump motors or other devices that utilize fluid to transfer energy. The function of the hydraulic pressure regulating component is to regulate the energy of the liquid, including regulating the pressure, flow rate and other parameters affecting the energy of the liquid. Types of the hydraulic pressure adjusting part include a liquid pressure adjusting valve, a liquid flow adjusting valve, a liquid direction adjusting valve, and other adjusting mechanisms that change the moving state of the liquid. The hydraulic execution component has the function of converting the energy of the liquid into mechanical energy and transmitting the mechanical energy outwards, overcoming the load to do work and completing the preset action or function. The types of hydraulic actuators include linear type actuators and rotary type actuators. The hydraulic auxiliary components have the functions of assisting the hydraulic power components, the hydraulic adjusting components and the hydraulic executing components in working, and the hydraulic auxiliary components comprise hydraulic oil tanks, hydraulic oil pipelines, connecting devices and hydraulic energy storage devices.

The second hydraulic system 300 is connected to the prime mover system 100 for absorbing energy from the prime mover, storing and assisting the prime mover drive when necessary. The second hydraulic system 300 includes hydraulic energy absorbing components, hydraulic energy conditioning components, hydraulic energy storage components, hydraulic energy output components, and auxiliary components. The hydraulic energy absorbing member is coupled to the prime mover for absorbing energy from the prime mover. Types of hydraulic energy absorbing components include hydraulic pump motors, other energy transfer and conversion elements having the function of hydraulic pump motors. The hydraulic energy adjusting component is used for adjusting part or all of parameters such as pressure, direction, flow and the like of the liquid, and the type of the hydraulic energy adjusting component comprises a pressure adjusting valve, a flow adjusting valve and a direction adjusting valve. Hydraulic energy storage components are used to store hydraulic energy, and include hydraulic accumulators of the type. The auxiliary components are used for assisting the hydraulic energy absorption component, the hydraulic energy adjusting component, the hydraulic energy storage component and the hydraulic energy output component to work, and the auxiliary components comprise a hydraulic oil tank, a hydraulic oil pipeline and a connecting device.

The electrical control system 400 is connected to the prime mover system 100, the first hydraulic system 200 and the second hydraulic system 300, and is configured to detect state parameters of the prime mover system 100, the first hydraulic system 200 and the second hydraulic system 300, calculate state data of the systems, and control the systems by outputting control signals. The electrical control system 400 includes a prime mover parameter measuring device, a first hydraulic system control device, a second hydraulic system measuring device, a second hydraulic system control device, and a controller. The function of the prime mover parameter measuring device is to measure the state parameter and the performance parameter of the prime mover and output the same to the parameter receiving part. Types of prime mover parameter measuring devices include prime mover speed measuring devices, torque measuring devices, and other prime mover parameter measuring devices. The first hydraulic system control device is used for controlling actions and functions of the first hydraulic system 200, and the types of the first hydraulic system control device comprise a control handle, a knob, a button, a pedal plate, a steering wheel, a switch, a throttle, a gearbox gear, a signal lamp, a remote control signal and the like. The second hydraulic system control devices are used to control the operation and functions of the second hydraulic system 300 and include control handles, knobs, buttons, foot pedals, steering wheels, switches, and other devices capable of controlling the second hydraulic system. The second measuring device of the hydraulic system is used for measuring the state parameters and the performance parameters of the second hydraulic system, and the types of the second measuring device of the hydraulic system comprise a liquid pressure measuring device, a liquid flow direction measuring device and the like. The controller is configured to calculate detected state parameters of the prime mover system 100, the first hydraulic system 200, and the second hydraulic system 300, control the systems by outputting a control signal, and shut down the engine 10 if the working devices driven by the first hydraulic system 200 and the second hydraulic system 300 are not operated and no operation command is received.

In the above structure, referring to fig. 2, the electrical control system 400 includes a rotation speed detecting device 20, a torque detecting device 30, a pressure sensor 90 and a controller 110, the first hydraulic system 200 includes a directional valve 40, a check valve 50, a first relief valve 60 and a second relief valve 70, the second hydraulic system 300 includes a hydraulic pump motor 120 and an accumulator 80, wherein the rotation speed detecting device 20 is connected to the engine 10 for detecting the rotation speed of the engine 10; a torque detection device 30 connected to the engine 10 for detecting a torque of the engine 10; the oil suction port of the hydraulic pump motor 120 is divided into two paths, one path is connected with the one-way valve 50, and the other path is connected with the energy accumulator 80 through the oil outlet of the reversing valve 40; the oil pressing port of the hydraulic pump motor 120 is divided into two paths, one path is connected with the first overflow valve 60, and the other path is connected with the energy accumulator 80 through the oil inlet of the reversing valve 40; the hydraulic pump motor 120 is used to absorb power of the engine 10 or assist the engine 10 in operation; the oil inlet of the second overflow valve 70 is connected with the energy accumulator 80; a pressure sensor 90 for detecting the accumulator 80 pressure; the controller 110 is electrically connected to the engine 10, the rotation speed detection device 20, the torque detection device 30, the reversing valve 40 and the first relief valve 60, respectively, and is configured to obtain an operating state of the engine 10 according to the rotation speed and the torque of the engine 10 detected by the rotation speed detection device 20 and the torque detection device 30; monitoring the power stored in the accumulator 80 according to the pressure of the accumulator 80 detected by the pressure sensor 90, and if the engine 10 needs to be started, controlling the reversing valve 40 to automatically start the engine 10 by the power stored in the accumulator 80; if the engine 10 is in a light load condition, the hydraulic pump motor 120 is controlled to charge the accumulator 80.

The hydraulic pressure that this embodiment provided opens stops device, its theory of operation as follows:

the controller 110 monitors all the working devices of the working machine, the operation signals of the driver, and the engine speed, and shuts down the engine when all the working device action signals are none, all the operation signals of the driver are none, and the engine speed is greater than 0; when the engine speed is 0, the accumulator pressure is greater than the preset pressure P2, and the driver operation signal is not all "none", the engine is started. The driver operation signal is at least one operation instruction of the working machine by the driver when the working machine is in a manned state, and comprises instruction signals of all drivers for operating the working machine, such as a steering wheel signal, a gear signal, an accelerator signal, an operation valve signal, an operation button signal and the like.

Further, as shown in fig. 3 and 4, fig. 4 is a functional block diagram of a first embodiment of the rotational speed control module shown in fig. 3, in this embodiment, the controller 110 includes a rotational speed control module 111, and the rotational speed control module 111 is configured to process an engine rotational speed signal n detected by the rotational speed detection device 20, and determine whether to start charging, and if so, charge the accumulator 80; if not, the accumulator 80 is charged. Further, the rotational speed control module 111 includes a first preset unit 1111, a first comparison unit 1112, and a first judgment unit 1113, where the first preset unit 1111 is configured to preset an accumulator pressure threshold n 1; a first comparison unit 1112, configured to compare the engine speed signal n detected by the speed detection device 20 with a preset accumulator pressure threshold n 1; the first judgment unit 1113 is configured to judge that charging needs to be started if the engine speed signal n is greater than the accumulator pressure threshold n1, output a control signal to the first hydraulic system 200 and the second hydraulic system 300, control the operation of the selector valve 40 and the first relief valve 60, and control the hydraulic pump motor 120 to charge the accumulator 80; and if the engine speed signal n is less than or equal to the accumulator pressure threshold n1, judging that the charging is required to be finished, outputting control signals to the first hydraulic system 200 and the second hydraulic system 300, controlling the reversing valve 40 and the first overflow valve 60 to stop operating, and controlling the hydraulic pump motor 120 to finish charging the accumulator 80.

Preferably, referring to fig. 3 and fig. 5, fig. 5 is a functional block schematic diagram of a second embodiment of the rotational speed control module shown in fig. 3, in this embodiment, the rotational speed control module 111 includes a first calculating unit 1114, a second preset unit 1115, a second comparing unit 1116 and a second judging unit 1117, the first calculating unit 1114 is configured to derive a rotational speed signal n of the engine 10 detected by the rotational speed detecting device 20 to obtain an engine rotational speed change rate n' of the rotational speed signal n of the engine changing with time; a second presetting unit 1115, configured to preset an engine rotation speed change rate threshold n' 1 in advance; a second comparing unit 1116, configured to compare the obtained engine speed change rate n 'with a preset engine speed change rate threshold value n' 1; a second determination unit 1117, configured to determine that liquid filling needs to be started if the engine speed change rate n 'is greater than the engine speed change rate threshold n' 1, output a control signal to the first hydraulic system 200 and the second hydraulic system 300, control the operation of the directional control valve 40 and the first overflow valve 60, and control the hydraulic pump motor 120 to fill the accumulator 80; and if the engine speed change rate n 'is less than or equal to the engine speed change rate threshold n' 1, judging that the liquid filling needs to be finished, outputting control signals to the first hydraulic system 200 and the second hydraulic system 300, controlling the reversing valve 40 and the first overflow valve 60 to stop acting, and controlling the hydraulic pump motor 120 to finish filling the liquid into the accumulator 80.

Further, referring to fig. 3 and 6, fig. 6 is a functional block diagram of a first embodiment of the torque control module shown in fig. 3, in this embodiment, the controller 110 includes a torque control module 112, and the torque control module 112 is configured to process the engine torque signal T detected by the torque detection device 30, determine whether to start charging, and if so, charge the accumulator 80; if not, the accumulator 80 is charged. Specifically, the torque control module 112 includes a third preset unit 1121, a third comparing unit 1122 and a third judging unit 1123, wherein the third preset unit 1121 is used for presetting an engine torque threshold T1; a third comparing unit 1122, configured to compare the engine torque signal T detected by the torque detecting device 30 with a preset engine torque threshold T1; a third determining unit 1123, configured to determine that charging needs to be started if the engine torque signal T is greater than the engine torque threshold T1, output a control signal to the first hydraulic system 200 and the second hydraulic system 300, control the operation of the selector valve 40 and the first relief valve 60, and control the hydraulic pump motor 120 to charge the accumulator 80; and if the engine torque signal T is smaller than or equal to the engine torque threshold T1, judging that the charging is required to be finished, outputting control signals to the first hydraulic system 200 and the second hydraulic system 300, controlling the reversing valve 40 and the first overflow valve 60 to stop operating, and controlling the hydraulic pump motor 120 to finish charging the accumulator 80.

Preferably, referring to fig. 3 and 7, fig. 7 is a functional block schematic diagram of a second embodiment of the torque control module shown in fig. 3, in this embodiment, the torque control module 112 includes a second calculating unit 1124, a fourth preset unit 1125, a fourth comparing unit 1126 and a fourth judging unit 1127, wherein the second calculating unit 1124 is configured to derive the engine torque signal T of the engine 10 detected by the torque detecting device 30 to find an engine torque change rate n' of the engine torque signal T changing with time; a fourth presetting unit 1125 for presetting an engine torque change rate threshold n' 1; a fourth comparing unit 1126 configured to compare the obtained engine torque change rate n 'with a preset engine torque change rate threshold n' 1; a fourth determining unit 1127, configured to determine that charging needs to be started if the engine torque change rate n 'is greater than the engine torque change rate threshold n' 1, output a control signal to the first hydraulic system 200 and the second hydraulic system 300, control the operation of the reversing valve 40 and the first relief valve 60, and control the hydraulic pump motor 120 to charge the accumulator 80; and if the engine torque change rate n 'is less than or equal to the engine torque change rate threshold n' 1, judging that the charging is required to be finished, outputting control signals to the first hydraulic system 200 and the second hydraulic system 300, controlling the reversing valve 40 and the first overflow valve 60 to stop acting, and controlling the hydraulic pump motor 120 to finish charging the accumulator 80.

Further, as shown in fig. 3 and 8, fig. 8 is a functional block diagram of an embodiment of the pressure control module shown in fig. 3, in the present embodiment, the controller 110 includes a pressure control module 113, and the pressure control module 113 is configured to process an accumulator pressure signal P of the accumulator 80 detected by the pressure sensor 90, and determine whether to start charging, if so, charge the accumulator 80; if not, the accumulator 80 is charged. Specifically, the pressure control module 113 includes a fifth preset unit 1131, a fifth comparison unit 1132 and a fifth judgment unit 1133, where the fifth preset unit 1131 is used to preset an accumulator pressure threshold P1; a fifth comparing unit 1132, configured to compare the accumulator pressure signal P of the accumulator 80 detected by the pressure sensor 90 with a preset accumulator pressure threshold P1; a fifth judging unit 1133, configured to judge that charging needs to be started if the accumulator pressure signal P is greater than the accumulator pressure threshold P1, output a control signal to the first hydraulic system 200 and the second hydraulic system 300, control the operation of the selector valve 40 and the first relief valve 60, and control the hydraulic pump motor 120 to charge the accumulator 80; and if the accumulator pressure signal P is smaller than or equal to the accumulator pressure threshold P1, judging that the charging is required to be finished, outputting control signals to the first hydraulic system 200 and the second hydraulic system 300, controlling the reversing valve 40 and the first overflow valve 60 to stop operating, and controlling the hydraulic pump motor 120 to finish charging the accumulator 80.

According to the hydraulic start-stop device provided by the embodiment, the power of the engine is simultaneously output to the external load and the energy accumulator, the energy accumulator is preferably ensured to be charged, and only after the energy accumulator is charged, the power of the engine is completely output to the external load. The control of the hydraulic start-stop device can be divided into two parts of the liquid filling process control and the liquid discharging process control of the energy accumulator, and the liquid discharging process control and the liquid filling process control are as follows:

one-time, liquid filling process control

1. Engine speed based control

The engine speed is representative of the power output capability of the engine, and therefore, charging of the accumulator may be initiated using the engine speed as a base signal. The specific control process is as follows:

s1: the controller processes and judges the engine speed signal n to obtain a conclusion whether to start liquid filling; the method for processing the engine speed signal n by the controller comprises the following steps: the method 1 includes the steps that one or more engine rotating speed thresholds are preset, the rotating speed range of an engine is divided into two or more rotating speed intervals, and when the rotating speed signal of the engine is in a certain rotating speed interval, the conclusion that whether liquid filling is started or not is judged to be yes. For example, an engine speed threshold n1 is preset, and when the engine speed signal n > n1, the conclusion of whether to start charging is judged to be yes; in the method 2, firstly, the engine speed signal n is derived, namely, firstly, the change rate n ' of the engine speed n along with time is obtained, then one or more thresholds are preset, the range of n ' is divided into two or more intervals, and when n ' is in certain intervals, the conclusion of judging whether to start liquid filling is yes. For example, a threshold n ' 1 is preset, and when the engine speed signal n ' > n ' 1, it is determined whether to start charging, and the conclusion is yes.

S2: if the conclusion of S1 is yes, the controller outputs control signals to the first hydraulic system and the second hydraulic system to control the first overflow valve and the hydraulic valve motor to act, and the hydraulic pump starts to charge the accumulator.

S3: and if the conclusion obtained by the S1 is 'no', the controller outputs control signals to the first hydraulic system and the second hydraulic system, controls the overflow valve and the hydraulic valve to stop and finishes the filling of the accumulator by the hydraulic pump.

2. Engine torque based control

The engine torque represents the magnitude of the load on the engine, and therefore, charging of the accumulator may be initiated using the engine torque as a base signal. The specific control process is as follows:

s1: the controller processes and judges the engine torque signal T to obtain a conclusion whether to start liquid filling; the method for processing the engine torque signal T by the controller comprises the following steps: the method 1 includes the steps that one or more engine torque thresholds are preset, the torque range of an engine is divided into two or more torque intervals, and when an engine speed signal is in a certain torque interval, the conclusion of judging whether to start liquid filling is yes. For example, an engine torque threshold T1 is preset, and when the engine torque signal T < T1, it is determined whether to initiate a charge; in the method 2, firstly, the engine torque signal T is derived, namely, firstly, the change rate T ' of the engine torque signal T along with the time is obtained, then one or more thresholds are preset, the range of T ' is divided into two or more intervals, and when the T ' is in certain intervals, the conclusion of judging whether to start the liquid filling is yes. For example, a threshold T ' 1 is preset, and when the engine torque signal T ' < T ' 1, it is determined whether to initiate a charge, and the conclusion is "Yes".

S3: if the conclusion obtained by the S1 is 'NO', the controller outputs control signals to the first hydraulic system and the second hydraulic system, controls the overflow valve and the hydraulic valve to stop, and the hydraulic pump finishes charging the accumulator.

3. Accumulator-based pressure control

The accumulator pressure represents the working capacity of the accumulator, so that charging of the accumulator can be initiated using the accumulator pressure as a base signal. The specific control process is as follows:

s1: the controller processes and judges the pressure signal P of the energy accumulator to obtain the conclusion whether to start liquid filling; the method for processing the accumulator pressure signal P by the controller comprises the following steps: presetting one or more pressure thresholds, dividing the pressure range of the accumulator into two or more intervals, and judging whether to start liquid filling when the pressure signal of the accumulator is in certain intervals, wherein the conclusion of 'yes' is judged. For example, an accumulator pressure threshold P1 is preset, and when the accumulator pressure signal P < P1, it is determined whether to initiate charging, and the determination is yes.

S2: if the conclusion obtained by the S1 is 'NO', the controller outputs control signals to the first hydraulic system and the second hydraulic system, controls the overflow valve and the hydraulic valve to stop, and the hydraulic pump finishes charging the accumulator.

In practice, one or more of the above three methods are often used simultaneously, for example:

controlling by adopting the rotating speed of the engine and the pressure of the energy accumulator;

controlling by adopting engine torque and accumulator pressure;

engine speed, torque and accumulator pressure are used for control.

Secondly, controlling the liquid discharging process

The hydraulic start-stop system has the following control logics in the liquid discharging process of an energy accumulator: when the engine is in a stop state and the controller finds a signal for starting the engine, the accumulator discharges liquid to drive the hydraulic motor, and the hydraulic motor drives the engine to start; and when the rotating speed of the engine reaches the preset rotating speed, the controller considers that the starting of the engine is finished, and the liquid discharging of the accumulator is stopped.

The method for controlling the liquid discharging process of the energy accumulator comprises the following steps:

1. based on driver operating signal and accumulator pressure control

The driver operation signal is an operation command of the driver to at least one of the working machines when the working machine is in a manned state, and includes command signals of all drivers operating the working machine, such as a steering wheel signal, a gear signal, an accelerator signal, an operation valve signal, and an operation button signal.

The driver operated signal represents a demand for engine power from the work machine and can therefore be used as a base signal to initiate a bleeding process of the accumulator, in which case the driver operated signal represents a demand for starting the engine.

Meanwhile, the control needs to be participated in according to the pressure signal of the energy accumulator, and the control logic is as follows: when the accumulator pressure is high, the accumulator may provide a power output; otherwise, if the accumulator pressure is low, the accumulator has little capacity to store and is not sufficient to provide the required power output. At this point, the accumulator pressure signal represents the internal power reserve.

Meanwhile, the controller monitors the engine speed signal and judges whether the engine is in a starting state or not. The method comprises the following steps: presetting one or more engine rotating speed threshold values, dividing the rotating speed range of the engine into two or more rotating speed intervals, and judging whether the engine is in a starting state when the rotating speed signal of the engine is in a certain rotating speed interval so as to obtain the conclusion of 'yes'. For example, an engine speed threshold n1 is preset, and when the engine speed signal n > n1, the conclusion of judging whether the engine is in the starting state is yes; the bleeding process of the accumulator is only started if the start demand for the engine and the internal power reserve are both yes and the conclusion whether the engine is in the start state is no. The specific control process is as follows:

s1: the controller processes and judges the driver operation signal S, the accumulator pressure signal P and the engine speed n to draw a conclusion whether the accumulator liquid discharge is started or not.

The method for processing the driver operation signal S by the controller comprises the following steps: the controller scans each monitored driver operation signal and judges whether the signal exists, and if at least one driver operation signal is scanned to be 'yes', whether the engine needs to be started is assigned to be 'yes'. For example, the controller scans that the throttle signal rises from 0 to some significant value, and assigns a "yes" value to whether it is desired to start the engine.

The method for processing the accumulator pressure signal P comprises the following steps: one or more accumulator pressure signal threshold values are preset, the accumulator pressure range is divided into two or more intervals, and when the accumulator pressure signal is in certain intervals, the conclusion that whether the accumulator has the capacity of discharging liquid is yes. For example, a threshold accumulator pressure value P1 is preset, and when the accumulator pressure signal P > P1, the conclusion of whether the accumulator has the capacity to discharge fluid is yes.

The processing method for the engine speed n comprises the following steps: presetting one or more engine rotating speed threshold values, dividing the rotating speed range of the engine into two or more rotating speed intervals, and judging whether the engine is in a starting state when the rotating speed signal of the engine is in a certain rotating speed interval so as to obtain the conclusion of 'yes'. For example, an engine speed threshold n1 is preset, and when the engine speed signal n > n1, the conclusion of whether the engine is in the starting state is yes.

When the conclusion of whether the engine needs to be started is yes, the conclusion of whether the accumulator has the capacity to discharge liquid is yes, and whether the engine is in the starting state is no, the conclusion of whether the accumulator discharging process is started is yes, and the conclusion of whether the output is no.

S2: if the conclusion obtained by the S1 is yes, the controller outputs control signals to the first hydraulic system and the second hydraulic system, controls the hydraulic valve motor to act, and starts the liquid discharging process of the accumulator.

S3: and if the conclusion obtained by the S1 is 'no', the controller outputs control signals to the first hydraulic system and the second hydraulic system, controls the hydraulic valve to stop working, and ends the liquid discharging process of the energy accumulator.

2. Based on environment identification signal and accumulator pressure control

The environment identification signal includes a signal light and an environment video. In some work applications, the operation of the work machine is limited by environmental signals, for example, in an industrial environment, the work machine needs to operate according to the indication of a signal lamp; under the urban traffic environment, vehicles need to travel according to traffic lights, and pedestrians need to wait to travel after passing through a sidewalk for courtesy.

The result of the signal light and the video recognition of the environment as an environment signal forms a limiting condition for the operation and behavior of the working machine and the vehicle, so that the tapping process of the energy accumulator can be started as a basic signal, in which case the environment signal represents the circumstances which the environment allows for the starting of the engine.

Meanwhile, the controller monitors the engine speed signal and judges whether the engine is in a starting state or not. The method comprises the following steps: presetting one or more engine rotating speed threshold values, dividing the rotating speed range of the engine into two or more rotating speed intervals, and judging whether the engine is in a starting state when the rotating speed signal of the engine is in a certain rotating speed interval so as to obtain the conclusion of 'yes'. For example, an engine speed threshold n1 is preset, and when the engine speed signal n > n1, the conclusion of judging whether the engine is in the starting state is yes;

the draining process of the accumulator is only started if the start allowance for the engine is yes, the internal power reserve is yes, and the conclusion whether the engine is in the starting state is no. The specific control process is as follows:

s1: the controller processes and judges the environmental signal, the accumulator pressure signal P and the engine speed n to obtain a conclusion whether to start the liquid discharge of the accumulator;

the method for processing the environment signal by the controller comprises the following steps: the camera is adopted to monitor and recognize the environment video, the controller assigns a value to whether the engine needs to be started or not according to the environment video recognition result, and when the environment video recognition result is yes to whether the engine is allowed to be started or not, the controller assigns a value to yes to whether the engine is started or not. For example, if the controller recognizes "allow action" to the signal light video, it assigns "yes" to whether it is necessary to start the engine.

3. Based on remote control signal and accumulator pressure control

The remote control signal is an operation signal of the work machine from the remote control center in an automatic driving state of the work machine.

The remote control signal represents the power demand of the engine by the working machine and can therefore be used as a base signal to initiate the tapping process of the accumulator, in which case the remote control signal represents the starting demand of the engine

Meanwhile, the controller monitors the engine speed signal and judges whether the engine is in a starting state or not. The method comprises the following steps: presetting one or more engine rotating speed threshold values, dividing the rotating speed range of the engine into two or more rotating speed intervals, and judging whether the engine is in a starting state when the rotating speed signal of the engine is in a certain rotating speed interval so as to obtain the conclusion of 'yes'. For example, an engine speed threshold n1 is preset, and when the engine speed signal n > n1, the conclusion of whether the engine is in the starting state is yes.

The bleeding process of the accumulator is only started if the start demand for the engine and the internal power reserve are both yes and the conclusion whether the engine is in the start state is no. The specific control process is as follows:

s1: the controller processes and judges a driver operation signal S, an energy accumulator pressure signal P and an engine speed n to obtain a conclusion whether to start the liquid discharging of the energy accumulator;

the method for processing the remote control signal by the controller comprises the following steps: the controller scans the monitored remote control signals and judges whether the remote control signals exist, and if at least one remote control signal is scanned to be 'yes', whether the value of the engine needing to be started is 'yes'. For example, the controller scans that the remote throttle signal rises from 0 to some significant value, and assigns a "yes" value to whether it is desired to start the engine.

The method for processing the accumulator pressure signal P comprises the following steps: one or more accumulator pressure signal threshold values are preset, the accumulator pressure range is divided into two or more intervals, and when the accumulator pressure signal is in certain intervals, the conclusion that whether the accumulator has the capacity of discharging liquid is yes. For example, an accumulator pressure threshold value P1 is preset, and when the accumulator pressure signal P > P1, the conclusion that whether the accumulator has the capacity of discharging liquid is yes;

S2: if the conclusion obtained by the S1 is yes, the controller outputs control signals to the first hydraulic system and the second hydraulic system, and controls the hydraulic valve to start to act, so that the process of discharging the accumulator is started.

The embodiment provides a hydraulic start-stop device, compared with the prior art, a prime power system, a first hydraulic system, a second hydraulic system and an electric control system are adopted, and when all working devices do not act and a driver has no operation instruction, an engine is turned off; when the controller considers that the engine needs to be started, the engine is automatically started through the power stored by the energy accumulator; when the engine is in a light load condition, the accumulator is charged. The hydraulic starting and stopping device provided by the embodiment has the advantages that the number of added elements is small, and the occupied space is small; the model selection specification of the engine can be reduced, and the total cost of the working machine is reduced; the oil consumption, the emission and the noise of the prime motor are reduced.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention. It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A hydraulic start-stop device, characterized by comprising a prime mover system (100), a first hydraulic system (200), a second hydraulic system (300) and an electric control system (400), wherein,

the prime mover system (100) comprising an engine (10) for providing a source of energy;

the first hydraulic system (200) is connected with the prime power system (100) and is used for transferring and converting energy provided by the prime power system (100) and outputting energy for external work to complete expected actions or functions of equipment;

the second hydraulic system (300) is connected with the motive power system (100) and used for absorbing and storing energy of the motive power system (100) and assisting the motive power system (100) to drive through the stored energy;

the electrical control system (400) is respectively connected with the prime power system (100), the first hydraulic system (200) and the second hydraulic system (300) and is used for detecting state parameters of the prime power system (100), the first hydraulic system (200) and the second hydraulic system (300); and if the working devices driven by the first hydraulic system (200) and the second hydraulic system (300) do not act and an operation command is not received, the engine (10) is shut down.

2. Hydraulic start-stop arrangement according to claim 1,

the electric control system (400) comprises a rotating speed detection device (20), a torque detection device (30), a pressure sensor (90) and a controller (110), the first hydraulic system (200) comprises a reversing valve (40), a one-way valve (50), a first overflow valve (60) and a second overflow valve (70), the second hydraulic system (300) comprises a hydraulic pump motor (120) and an accumulator (80), wherein,

the rotating speed detection device (20) is connected with the engine (10) and is used for detecting the rotating speed of the engine (10);

the torque detection device (30) is connected with the engine (10) and is used for detecting the torque of the engine (10);

an oil suction port of the hydraulic pump motor (120) is divided into two paths, one path is connected with the one-way valve (50), and the other path is connected with the energy accumulator (80) through an oil outlet of the reversing valve (40); the oil pressing port of the hydraulic pump motor (120) is divided into two paths, one path is connected with the first overflow valve (60), and the other path is connected with the energy accumulator (80) through the oil inlet of the reversing valve (40); the hydraulic pump motor (120) is used for absorbing the power of the engine (10) or assisting the engine (10) to work;

an oil inlet of the second overflow valve (70) is connected with the energy accumulator (80); the pressure sensor (90) is used for detecting the pressure of the accumulator (80);

the controller (110) is respectively electrically connected with the engine (10), the rotating speed detection device (20), the torque detection device (30), the reversing valve (40) and the first overflow valve (60) and is used for acquiring the working state of the engine (10) according to the rotating speed and the torque of the engine (10) detected by the rotating speed detection device (20) and the torque detection device (30); and monitoring the stored power of the accumulator (80) according to the pressure of the accumulator (80) detected by the pressure sensor (90), and controlling the reversing valve (40) to automatically start the engine (10) by the stored power of the accumulator (80) if the engine (10) needs to be started; and if the engine (10) is in a light load working condition, controlling the hydraulic pump motor (120) to charge the energy accumulator (80).

3. Hydraulic start-stop arrangement according to claim 2,

the controller (110) comprises a rotational speed control module (111),

the rotating speed control module (111) is used for processing an engine rotating speed signal n detected by the rotating speed detection device (20) and judging whether to start liquid filling, and if so, filling liquid into the energy accumulator (80); if not, the accumulator (80) is charged.

4. Hydraulic start-stop arrangement according to claim 3,

the rotating speed control module (111) comprises a first preset unit (1111), a first comparison unit (1112) and a first judgment unit (1113),

the first preset unit (1111) is used for presetting an accumulator pressure threshold value n 1;

the first comparison unit (1112) is used for comparing the engine speed signal n detected by the speed detection device (20) with a preset accumulator pressure threshold value n 1;

the first judging unit (1113) is configured to judge that charging needs to be started if the engine speed signal n is greater than the accumulator pressure threshold n1, output a control signal to the first hydraulic system (200) and the second hydraulic system (300), control the reversing valve (40) and the first overflow valve (60) to act, and control the hydraulic pump motor (120) to charge the accumulator (80); and if the engine speed signal n is less than or equal to the accumulator pressure threshold n1, judging that the charging needs to be finished, outputting control signals to the first hydraulic system (200) and the second hydraulic system (300), controlling the reversing valve (40) and the first overflow valve (60) to stop acting, and controlling the hydraulic pump motor (120) to finish charging the accumulator (80).

5. Hydraulic start-stop arrangement according to claim 3,

the rotating speed control module (111) comprises a first calculating unit (1114), a second preset unit (1115), a second comparing unit (1116) and a second judging unit (1117),

the first calculation unit (1114) is used for obtaining the engine speed change rate n' of the change of the engine speed signal n along with the time by differentiating the speed signal n of the engine (10) detected by the speed detection device (20);

the second preset unit (1115) is used for presetting an engine speed change rate threshold value n' 1 in advance;

the second comparison unit (1116) is used for comparing the calculated engine speed change rate n 'with a preset engine speed change rate threshold value n' 1;

the second judgment unit (1117) is configured to judge that charging needs to be started if the engine speed change rate n 'is greater than the engine speed change rate threshold n' 1, output a control signal to the first hydraulic system (200) and the second hydraulic system (300), control the operation of the selector valve (40) and the first overflow valve (60), and control the hydraulic pump motor (120) to charge the accumulator (80); if the engine speed change rate n 'is less than or equal to the engine speed change rate threshold n' 1, determining that the liquid filling needs to be finished, outputting control signals to the first hydraulic system (200) and the second hydraulic system (300), controlling the reversing valve (40) and the first overflow valve (60) to stop acting, and controlling the hydraulic pump motor (120) to finish the liquid filling to the accumulator (80).

6. Hydraulic start-stop arrangement according to claim 2,

the controller (110) includes a torque control module (112),

the torque control module (112) is configured to process an engine torque signal T detected by the torque detection device (30), determine whether to start charging, and charge the accumulator (80) if yes; if not, the accumulator (80) is charged.

7. Hydraulic start-stop arrangement according to claim 6,

the torque control module (112) comprises a third preset unit (1121), a third comparison unit (1122) and a third judgment unit (1123),

the third presetting unit (1121) is used for presetting an engine torque threshold value T1;

the third comparing unit (1122) is used for comparing the engine torque signal T detected by the torque detecting device (30) with the preset engine torque threshold value T1;

the third judging unit (1123) is configured to judge that charging needs to be started if the engine torque signal T is greater than the engine torque threshold T1, output a control signal to the first hydraulic system (200) and the second hydraulic system (300), control the operation of the selector valve (40) and the first relief valve (60), and control the hydraulic pump motor (120) to charge the accumulator (80); and if the engine torque signal T is smaller than or equal to the engine torque threshold T1, judging that the charging is required to be finished, outputting control signals to the first hydraulic system (200) and the second hydraulic system (300), controlling the reversing valve (40) and the first overflow valve (60) to stop acting, and controlling the hydraulic pump motor (120) to finish charging the accumulator (80).

8. Hydraulic start-stop arrangement according to claim 6,

the torque control module (112) comprises a second calculating unit (1124), a fourth preset unit (1125), a fourth comparing unit (1126) and a fourth judging unit (1127),

the second calculating unit (1124) for deriving an engine torque signal T of the engine (10) detected by the torque detecting device (30) to find an engine torque change rate n' of the engine torque signal T changing with time;

the fourth preset unit (1125) is used for presetting an engine torque change rate threshold n' 1;

the fourth comparison unit (1126) is used for comparing the obtained engine torque change rate n 'with a preset engine torque change rate threshold value n' 1;

the fourth judging unit (1127) is configured to judge that charging needs to be started if the engine torque change rate n 'is greater than the engine torque change rate threshold n' 1, output a control signal to the first hydraulic system (200) and the second hydraulic system (300), control the operation of the selector valve (40) and the first relief valve (60), and control the hydraulic pump motor (120) to charge the accumulator (80); and if the engine torque change rate n 'is less than or equal to the engine torque change rate threshold n' 1, judging that the charging needs to be finished, outputting control signals to the first hydraulic system (200) and the second hydraulic system (300), controlling the reversing valve (40) and the first overflow valve (60) to stop acting, and controlling the hydraulic pump motor (120) to finish charging the accumulator (80).

9. Hydraulic start-stop arrangement according to claim 2,

the controller (110) comprises a pressure control module (113),

the pressure control module (113) is configured to process an accumulator pressure signal P of the accumulator (80) detected by the pressure sensor (90), determine whether to start charging, and charge the accumulator (80) if yes; if not, the accumulator (80) is charged.

10. Hydraulic start-stop arrangement according to claim 9,

the pressure control module (113) comprises a fifth preset unit (1131), a fifth comparison unit (1132) and a fifth judgment unit (1133),

the fifth preset unit (1131) is used for presetting an accumulator pressure threshold value P1;

the fifth comparison unit (1132) is configured to compare an accumulator pressure signal P of the accumulator (80) detected by the pressure sensor (90) with a preset accumulator pressure threshold P1;

the fifth judging unit (1133) is configured to judge that charging needs to be started if the accumulator pressure signal P is greater than the accumulator pressure threshold P1, output a control signal to the first hydraulic system (200) and the second hydraulic system (300), control the operation of the selector valve (40) and the first relief valve (60), and control the hydraulic pump motor (120) to charge the accumulator (80); and if the accumulator pressure signal P is smaller than or equal to the accumulator pressure threshold P1, judging that the charging needs to be finished, outputting control signals to the first hydraulic system (200) and the second hydraulic system (300), controlling the reversing valve (40) and the first overflow valve (60) to stop acting, and controlling the hydraulic pump motor (120) to finish charging the accumulator (80).