CN215334389U

CN215334389U - Hydraulic system suitable for hybrid power

Info

Publication number: CN215334389U
Application number: CN202120443800.6U
Authority: CN
Inventors: 余学浩; 张恒先; 任宗丹; 李亚南
Original assignee: Chery Automobile Co Ltd
Current assignee: Chery Automobile Co Ltd
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2021-12-28
Anticipated expiration: 2031-03-01

Abstract

The utility model belongs to an automobile hydraulic system, and relates to a hydraulic system for a hybrid power gearbox. The system adopts a motor or a gearbox to drive a main mechanical pump to operate, a TCU controls a 12V low-pressure motor to drive an electric pump to operate and assist according to requirements, a main oil path comprises a low-pressure loop and a high-pressure loop, the high-pressure loop is used for meeting the high oil pressure working requirements of a clutch and the like, the low-pressure loop is used for meeting the high flow requirements of the motor and the like, and the main mechanical pump is driven by the motor or an engine or the gearbox and is provided with a self-circulation loop for the reverse rotation of the mechanical pump when a vehicle backs up, so that the reverse rotation requirement of the mechanical pump when the vehicle backs up is met.

Description

Hydraulic system suitable for hybrid power

Technical Field

The utility model belongs to an automobile hydraulic system, and particularly relates to a hydraulic system for a hybrid power transmission.

Background

With the economic development and the technological progress, the automobile not only plays the role of a travel tool in the life with fast pace and high efficiency, but also is a second moving family in the mind of people. Therefore, the functions of automobiles are more and more, the requirements for intellectualization, comfort, power and the like are higher and higher, and meanwhile, a series of social problems are brought by the increase of the vehicle conservation quantity, the exhaustion of fossil energy and the deterioration of the atmospheric environment.

New energy vehicles including pure electric vehicles, hybrid electric vehicles and the like have become mature as attempts to solve energy exhaustion and environmental pollution. The whole case places higher demands on the hydraulic system for the DHT route, abbreviated by DCT derived from a dual clutch automatic transmission. The motor is added on the basis of DCT as a power source, so that the requirements of flow and heat dissipation are greatly improved, and the requirement of low-speed oil pressure is improved due to the larger torque requirement at low speed. This presents a significant challenge for a simple hydraulic circuit for supplying oil to a conventional single mechanical pump.

If the traditional hydraulic system is improved, on one hand, the displacement of the mechanical pump is selected too much, so that the efficiency of the whole tank is reduced, and on the other hand, the partial harsh working conditions still face the dilemma of insufficient oil pressure and flow.

With the development of electrical appliances, the electric pump products are mature day by day, which provides possibility for a dual-pump mode with a mechanical pump as a main mode and an electric pump as an auxiliary mode. The electric pump can reasonably complement the capacity of the mechanical pump. In addition, the scheme that one high-pressure loop is used for meeting the high oil pressure requirements of the clutch and the like and one low-pressure loop is used for meeting the high flow requirements of the motor and the like also complements the oil pressure and flow requirements under severe working conditions. How to ensure the normal operation of the control loop under the condition of backing operation is a fundamental problem which needs to be solved urgently.

Disclosure of Invention

The utility model aims to provide a hydraulic system suitable for hybrid power, which ensures that hydraulic oil in the reversing process of a mechanical pump circulates in a reversing loop when a vehicle is reversed so as to avoid interference with a main oil way.

In order to achieve the purpose, the utility model adopts the following technical scheme: a hydraulic system suitable for hybrid power comprises an oil pan and a filter, wherein the liquid outlet ends of the filter are respectively connected to an electric pump and a mechanical pump, the liquid outlet ends of the electric pump and the mechanical pump are connected in parallel and then connected to a main oil circuit, the main oil circuit comprises a low-pressure loop and a high-pressure loop, the electric pump is driven by a connected low-pressure motor E, the mechanical pump is driven by a connected motor or a gearbox M, and a self-circulation loop which is conducted when the mechanical pump rotates reversely is connected between the liquid inlet end and the liquid outlet end of the mechanical pump.

The system adopts a motor or a gearbox M to drive a main mechanical pump to operate, a TCU controls a 12V low-voltage motor E to drive an electric pump to operate and assist according to the whole box requirement, a main oil path comprises a low-voltage loop and a high-voltage loop, the high-voltage loop is used for meeting the high oil pressure working requirements of a clutch, and the low-voltage loop is used for meeting the high flow requirements of the motor.

Brief description of the drawings

FIG. 1 is a schematic diagram of the principles of the present invention;

FIG. 2 is a schematic view of the present invention operating in a park generating mode;

FIG. 3 is a schematic diagram of the operation of the start-up acceleration mode of the present invention;

FIG. 4 is a schematic diagram of the operation of the present invention in the medium speed mode;

FIG. 5 is a schematic illustration of the high speed mode operation of the present invention;

fig. 6 is a schematic diagram of the reverse mode operation of the present invention.

A hydraulic system suitable for hybrid power comprises an oil pan 10 and a filter 20, wherein the liquid outlet end of the filter 20 is respectively connected to an electric pump 30 and a mechanical pump 50, the liquid outlet ends of the electric pump 30 and the mechanical pump 50 are connected in parallel and then connected to a main oil circuit, the main oil circuit comprises a low-pressure circuit 81 and a high-pressure circuit 82, the electric pump 30 is driven by a connected low-pressure motor E31, the mechanical pump 50 is driven by a connected motor or a gearbox M51, and a self-circulation circuit which is conducted when the mechanical pump 50 rotates reversely is connected between the liquid inlet end and the liquid outlet end of the mechanical pump 50.

The self-circulation loop comprises a one-way valve I60, and the one-way valve I60 is closed when the pressure oil is pumped out from the liquid outlet end of the mechanical pump 50 during operation.

The liquid outlet end of the mechanical pump 50 is connected with the liquid inlet end of the overflow valve 70, and the liquid outlet end of the overflow valve 70 is connected to the main oil path. The relief valve 70 ensures that the pressure oil pumped by the mechanical pump 50 can be delivered to the main oil path, and when the mechanical pump 50 is stopped and the electric pump 30 is operated, the pressure oil on the main oil path cannot reach the mechanical pump 50, so that the relief valve has an isolation function.

The liquid outlet end of the electric pump 30 passes through a second check valve 40, the conduction direction of the second check valve 40 is the direction of pumping high-pressure oil out of the electric pump 30, and the liquid outlet end of the second check valve 40 is connected with the main oil way. The second check valve 40 also has the function of one-way conduction and isolation.

The present invention is described in further detail below with reference to specific modes of operation.

As shown in fig. 1, the mechanical pump 50 and the electric pump 30 work together to provide a flow rate to the main oil path, the main oil path regulating valve regulates the oil pressure of the main oil path and the flow rate to the low-pressure circuit 81, and the pressure reducing valve reduces the pressure to the low-pressure circuit 81, so that the oil pressure and flow rate requirements under severe working conditions are met under the condition of improving the efficiency.

As shown in fig. 2, when the vehicle is stopped to generate electricity, the engine drives the generator to provide electric energy as the low-voltage motor E31 and drives the low-voltage motor E31, at this time, the oil pressure and flow rate required by the system are low, the electric pump 30 operates at rated power to provide oil with certain pressure and flow rate, and the main oil path regulating valve controls the main oil path to be at low oil pressure. Part of the oil is reduced in pressure to the low-pressure loop 81 through a pressure reducing valve, so that the cooling flow requirements of components such as a motor and the like are met; a portion of the oil is routed to the high pressure circuit 82 to meet the high pressure oil requirements of the components such as the clutch.

As shown in fig. 3, in order to reduce the loss of the mechanical pump 50 at high speed, the displacement of the mechanical pump 50 is appropriately reduced, which is advantageous to reduce the energy loss of the mechanical pump 50 at high speed, but which also results in insufficient capacity of the mechanical pump 50 at low speed. At this time, the electric pump 30 is started as an auxiliary supplementary flow rate. Meanwhile, the main oil way regulating valve controls the main oil way to have larger oil pressure and flow so as to meet the requirements of large torque transmission and large flow for cooling.

After reaching a certain speed into a medium speed, the speed of the mechanical pump 50 may provide sufficient flow, as shown in fig. 4, to take the electric pump 30 out of service. Meanwhile, the main oil way regulating valve is controlled to regulate the oil pressure value of the main oil way in real time by taking the oil pressure and flow demand of each component of the whole box as a target, the pressure reducing valve regulates the flow of the cooling circuit according to the main oil pressure value, and the high-pressure circuit 82 controls a clutch, a synchronizer and the like through an electromagnetic valve to realize the functions of gear shifting and the like.

As shown in fig. 5, after reaching a certain rotation speed and entering a high speed, the electric pump 30 is still inactive at this time, the rotation speed of the mechanical pump 50 is high to provide a flow higher than required, the main oil path regulating valve moves the valve core to the right continuously to regulate the excess flow back to the oil pan, so as to avoid the excess flow entering the cooling circuit to cause energy loss and increase the load of the cooler. The rest is similar to the medium speed mode principle.

As shown in fig. 6, when the vehicle is reversed, the mechanical pump 50 is reversed and cannot supply a flow rate, and internal circulation is performed to ensure lubrication of itself. The electric pump 30 is started to provide oil, and the main oil passage regulating valve controls the main oil passage at a lower oil pressure and flow rate. Part of the oil is reduced in pressure to the low-pressure loop 81 through a pressure reducing valve, so that the cooling flow requirements of components such as a motor and the like are met; a portion of the oil is routed to the high pressure circuit 82 to meet the high pressure oil requirements of the components such as the clutch. When the vehicle is reversed, the mechanical pump 50 rotates in the reverse direction and no high-pressure oil is supplied to the main oil passage.

Claims

1. The utility model provides a hydraulic system suitable for hybrid, including oil pan (10), filter (20), the play liquid end of filter (20) connects to electric pump (30), mechanical pump (50) respectively, the play liquid end of electric pump (30), mechanical pump (50) is connected to the working connection after connecting in parallel, the working connection includes low-pressure return circuit (81) and high-pressure return circuit (82), electric pump (30) are driven by the low-pressure motor E (31) who connects, mechanical pump (50) are driven by motor or gearbox M (51) that connect, its characterized in that: the self-circulation loop which is conducted when the mechanical pump (50) reverses is connected between the liquid inlet end and the liquid outlet end of the mechanical pump (50).

2. The hydraulic system for a hybrid according to claim 1, wherein: the self-circulation loop comprises a first check valve (60), and the first check valve (60) is closed when the pressure oil is pumped out from the liquid outlet end of the mechanical pump (50) during operation.

3. The hydraulic system for a hybrid according to claim 1 or 2, wherein: the liquid outlet end of the mechanical pump (50) is connected with the liquid inlet end of the overflow valve (70), and the liquid outlet end of the overflow valve (70) is connected to the main oil way.

4. The hydraulic system for a hybrid according to claim 1, wherein: the liquid outlet end of the electric pump (30) passes through a second check valve (40), the conduction direction of the second check valve (40) is the direction in which the electric pump (30) pumps high-pressure oil, and the liquid outlet end of the second check valve (40) is connected with the main oil way.