CN107588189B - Hydraulic gear shifting control system of double-clutch automatic transmission - Google Patents

Abstract

The hydraulic gear shifting control system of the double-clutch automatic transmission comprises a pressure control electromagnetic valve, a flow control electromagnetic valve, a first switch electromagnetic valve, a second switch electromagnetic valve, a third switch electromagnetic valve, a fourth switch electromagnetic valve, a first gear switch valve, a second gear switch valve, a third gear switch valve, a fourth gear switch valve, a first gear shifting oil cylinder, a second gear shifting oil cylinder, a third gear shifting oil cylinder and a fourth gear shifting oil cylinder, wherein the four switch electromagnetic valves respectively control the four gear switch valves to change directions, and the four gear switch valves respectively control the four gear shifting oil cylinders to shift gears. The automatic transmission gear-shifting control system has the advantages that the electromagnetic valves and the slide valve combination which are as few as possible are adopted in the embodiment, gear-shifting control of eight gears is achieved, dual control of gear-shifting pressure and flow is achieved through the pressure control electromagnetic valve and the flow control electromagnetic valve, the gear-shifting process is controlled more accurately by the hydraulic system, accurate control of the gear-shifting process can be achieved better, the system is lighter, and control logic is simpler.

Description

Hydraulic gear shifting control system of double-clutch automatic transmission

Technical Field

The invention relates to the technical field of automatic transmissions, in particular to a hydraulic gear shifting control system of a double-clutch automatic transmission.

Background

With the advancement of technology, the way of realizing speed change of automobiles gradually evolves from manual speed change to automatic speed change, and the automatic speed change is realized through an automatic transmission. The double-clutch automatic transmission is popular in the market due to the advantages of high transmission efficiency and the like, the double-clutch automatic transmission adopts two clutches, one clutch is used for controlling odd gears, the other clutch is used for controlling even gears, and a gear shifting program is completed by automatically switching between the two clutches, so that power gear shifting in the gear shifting process can be realized, namely, power is not interrupted in the gear shifting process, and the running comfort of a vehicle is improved.

When the automatic transmission realizes automatic gear shifting, a gear shifting actuating mechanism is needed as a system part, the function of the automatic gear shifting is realized, and a hydraulic gear shifting actuating mechanism is mostly adopted at present. Shifting is generally accomplished by a synchronizer keyed to and rotating with an associated shaft, provided on one or both sides with gears providing different gear ratios, which is shifted axially and into engagement with adjacent gears under the action of a shift actuator, coupling the gears to the shaft to achieve gear to shaft synchronization, and thereby output power.

The existing double-clutch automatic transmission mostly adopts eight gears (including reverse gears), and a hydraulic gear shifting control system is used for controlling a gear shifting actuating mechanism so as to complete gear shifting operation of the eight gears. In the prior art, gear shifting control is realized by using the combination of electromagnetic valves and slide valves as few as possible, wherein most technical schemes mainly adopt pressure control, and the moving speed of a gear shifting actuating mechanism cannot be accurately controlled so as to realize accurate control of a gear shifting process.

Disclosure of Invention

The invention aims to provide a hydraulic gear-shifting control system of a double-clutch automatic transmission, which realizes the accurate control of a gear-shifting executing mechanism in the gear-shifting process by combining electromagnetic valves and slide valves as few as possible, so that the system is lighter and the control logic is simpler.

The embodiment of the invention provides a hydraulic gear-shifting control system of a double-clutch automatic transmission, which comprises a pressure control electromagnetic valve, a flow control electromagnetic valve, a first switch electromagnetic valve, a second switch electromagnetic valve, a third switch electromagnetic valve, a fourth switch electromagnetic valve, a first gear position switch valve, a second gear position switch valve, a third gear position switch valve, a fourth gear position switch valve, a first gear-shifting oil cylinder, a second gear-shifting oil cylinder, a third gear-shifting oil cylinder and a fourth gear-shifting oil cylinder, wherein an outlet of the pressure control electromagnetic valve is connected with an inlet of the flow control electromagnetic valve, an outlet of the flow control electromagnetic valve is connected with an inlet of the first gear position switch valve, an inlet of the second gear position switch valve, an inlet of the third gear position switch valve and an inlet of the fourth gear position switch valve, an outlet of the first gear position switch valve is connected with an oil cavity of the first gear-shifting oil cylinder, the outlet of the second gear switch valve is connected with the oil cavity of the second gear shifting oil cylinder, the outlet of the third gear switch valve is connected with the oil cavity of the third gear shifting oil cylinder, the outlet of the fourth gear switch valve is connected with the oil cavity of the fourth gear shifting oil cylinder, the outlet of the first switch electromagnetic valve is connected with the control end of the first gear switch valve, the first gear switch valve is controlled by the first switch electromagnetic valve to change direction, the outlet of the second switch electromagnetic valve is connected with the control end of the second gear switch valve, the second gear switch valve is controlled by the second switch electromagnetic valve to change direction, the outlet of the third switch electromagnetic valve is connected with the control end of the third gear switch valve, the third gear switch valve is controlled by the third switch electromagnetic valve to change direction, the outlet of the fourth switch electromagnetic valve is connected with the control end of the fourth gear switch valve, the fourth gear switch valve is controlled by the fourth switch electromagnetic valve to perform reversing, and the inlet of the pressure control electromagnetic valve, the inlet of the first switch electromagnetic valve, the inlet of the second switch electromagnetic valve, the inlet of the third switch electromagnetic valve and the inlet of the fourth switch electromagnetic valve are all connected with the main oil way.

Further, the pressure control solenoid valve has an inlet and an outlet, the flow control solenoid valve has an inlet and two outlets, the inlet of the pressure control solenoid valve is connected to the main oil path, the outlet of the pressure control solenoid valve is connected to the inlet of the flow control solenoid valve, and the two outlets of the flow control solenoid valve are connected to the first gear switch valve, the second gear switch valve, the third gear switch valve and the fourth gear switch valve.

Further, the flow control electromagnetic valve can be switched between a first working position and a second working position, and when the flow control electromagnetic valve is in the first working position, the inlet of the flow control electromagnetic valve is communicated with one of the two outlets of the flow control electromagnetic valve; when the flow control electromagnetic valve is in the second working position, the inlet of the flow control electromagnetic valve is communicated with the other of the two outlets of the flow control electromagnetic valve.

Further, the first switching solenoid valve has an inlet and an outlet, the second switching solenoid valve has an inlet and an outlet, the third switching solenoid valve has an inlet and an outlet, the fourth switching solenoid valve has an inlet and an outlet, the first position switching valve has two inlets, two outlets and a control terminal, the second position switching valve has two inlets, two outlets and a control terminal, the third position switching valve has two inlets, two outlets and a control terminal, the fourth position switching valve has two inlets, two outlets and a control terminal, the inlet of the first switching solenoid valve, the inlet of the second switching solenoid valve, the inlet of the third switching solenoid valve and the inlet of the fourth switching solenoid valve are connected to the main oil passage, the outlet of the first switching solenoid valve is connected to the control terminal of the first position switching solenoid valve, the outlet of the second switch electromagnetic valve is connected with the control end of the second gear position switch valve, the outlet of the third switch electromagnetic valve is connected with the control end of the third gear position switch valve, the outlet of the fourth switch electromagnetic valve is connected with the control end of the fourth gear position switch valve, two inlets of the first gear position switch valve are respectively connected with two outlets of the flow control electromagnetic valve, two inlets of the second gear position switch valve are respectively connected with two outlets of the flow control electromagnetic valve, two inlets of the third gear position switch valve are respectively connected with two outlets of the flow control electromagnetic valve, two inlets of the fourth gear position switch valve are respectively connected with two outlets of the flow control electromagnetic valve, two outlets of the first gear position switch valve are respectively connected with two oil cavities of the first gear shifting oil cylinder, two outlets of the second gear position switch valve are respectively connected with two oil cavities of the second gear shifting oil cylinder, two outlets of the third gear switch valve are respectively connected with two oil cavities of the third gear shifting oil cylinder, and two outlets of the fourth gear switch valve are respectively connected with two oil cavities of the fourth gear shifting oil cylinder.

Further, the pressure control solenoid valve is a slide valve type pressure control proportional solenoid valve, the flow control solenoid valve is a slide valve type flow control proportional solenoid valve, and the first gear switch valve, the second gear switch valve, the third gear switch valve and the fourth gear switch valve are all slide valve type hydraulic control directional control valves.

Further, the hydraulic shift control system further includes a first clutch solenoid valve, a second clutch solenoid valve, and a clutch relief valve, the first clutch solenoid valve having an inlet and an outlet, the second clutch solenoid valve having an inlet and an outlet, the inlet of the first clutch solenoid valve and the inlet of the second clutch solenoid valve both being connected to the main oil passage, the clutch relief valve having two inlets, two outlets, and a control end, the two inlets of the clutch relief valve being connected to the outlet of the first clutch solenoid valve and the outlet of the second clutch solenoid valve, respectively, the two outlets of the clutch relief valve being connected to the first clutch and the second clutch, respectively, the outlets of two of the first to fourth switch solenoid valves being simultaneously connected to the control end of the clutch relief valve.

Further, the hydraulic gear shifting control system further comprises a fifth switch electromagnetic valve, a parking control valve and a parking oil cylinder, wherein the fifth switch electromagnetic valve is provided with an inlet and an outlet, the parking control valve is provided with an inlet, two outlets and a control end, the inlet of the fifth switch electromagnetic valve and the inlet of the parking control valve are connected with the main oil way, the outlet of the fifth switch electromagnetic valve is connected with the control end of the parking control valve, and the two outlets of the parking control valve are respectively connected with two oil cavities of the parking oil cylinder.

Further, two of the first to fourth switching solenoid valves are integrated into one three-position four-way switching solenoid valve, and the other two of the first to fourth switching solenoid valves are integrated into the other three-position four-way switching solenoid valve.

Further, the hydraulic gear-shifting control system further comprises a second pressure control solenoid valve and a main oil circuit pressure regulating valve, wherein the second pressure control solenoid valve is provided with an inlet and an outlet, the main oil circuit pressure regulating valve is provided with an inlet, two outlets and two control ends, the inlet of the second pressure control solenoid valve is connected with the main oil circuit, the outlet of the second pressure control solenoid valve is connected with the first control end of the main oil circuit pressure regulating valve, the inlet and the second control end of the main oil circuit pressure regulating valve are simultaneously connected with the main oil circuit, the first outlet of the main oil circuit pressure regulating valve is connected with an oil tank, and the second outlet of the main oil circuit pressure regulating valve is communicated with a lubricating and cooling oil circuit.

In the embodiment of the invention, the combination of the electromagnetic valve and the slide valve is adopted as few as possible, the gear shifting control of the automatic transmission with eight gears is realized, and the pressure control electromagnetic valve and the flow control electromagnetic valve are used for realizing the dual control of the gear shifting pressure and the flow on the basis of realizing the gear shifting control of the transmission, so that a hydraulic system can control the gear shifting process more accurately, the accurate control of the gear shifting process can be better realized, the use of the slide valve is reduced, the system is more portable, and the control logic is simpler.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are described in detail with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic configuration diagram of a hydraulic shift control system of a dual clutch automatic transmission according to a first embodiment of the present invention.

Fig. 2 is a schematic configuration diagram of a hydraulic shift control system of a dual clutch automatic transmission according to a second embodiment of the present invention.

Detailed Description

To further explain the technical means and effects of the present invention adopted to achieve the predetermined objects, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

The embodiment of the invention provides a hydraulic gear shifting control system for a double-clutch automatic transmission, aiming at better meeting the hydraulic gear shifting control requirement of the automatic transmission by using the combination of electromagnetic valves and slide valves as few as possible.

[ first embodiment ]

Fig. 1 is a schematic structural diagram of a hydraulic shift control system of a dual clutch automatic transmission according to a first embodiment of the present invention, and referring to fig. 1, the hydraulic shift control system includes a pressure control solenoid valve 11, a flow control solenoid valve 21, a first on-off solenoid valve 31, a second on-off solenoid valve 32, a third on-off solenoid valve 33, a fourth on-off solenoid valve 34, a first shift position on-off valve 41, a second shift position on-off valve 42, a third shift position on-off valve 43, a fourth shift position on-off valve 44, a first shift cylinder 51, a second shift cylinder 52, a third shift cylinder 53, and a fourth shift cylinder 54.

The pressure control solenoid valve 11 has an inlet A1 and an outlet B1, the inlet A1 of the pressure control solenoid valve 11 is connected to the main oil passage 10, and the outlet B1 of the pressure control solenoid valve 11 is connected to the flow control solenoid valve 21, so that the pressure oil output from the outlet B1 of the pressure control solenoid valve 11 can enter the first shift switch valve 41 via the flow control solenoid valve 21 to push the first shift cylinder 51 to perform a shift operation, or enter the second shift switch valve 42 via the flow control solenoid valve 21 to push the second shift cylinder 52 to perform a shift operation, or enter the third shift switch valve 43 via the flow control solenoid valve 21 to push the third shift cylinder 53 to perform a shift operation, or enter the fourth shift switch valve 44 via the flow control solenoid valve 21 to push the fourth shift cylinder 54 to perform a shift operation.

The required shift pressure will usually be different when shifting in different gears. In order to realize that the shifting pressure output by the outlet B1 of the pressure control electromagnetic valve 11 can meet the shifting requirement under different gears, in this embodiment, the pressure control electromagnetic valve 11 is a slide valve type pressure control proportional electromagnetic valve, and the pressure of the outlet B1 of the pressure control electromagnetic valve 11 is fed back to one end of the pressure control electromagnetic valve 11 through an oil path (shown in fig. 1 as being fed back to a spring load end). Therefore, when the pressure control solenoid valve 11 is in operation, the spool of the pressure control solenoid valve 11 can regulate and control the output pressure of the outlet B1 under the combined action of the electromagnetic force, the spring load force and the hydraulic feedback force. That is, by controlling the value of the current input to the electromagnet of the pressure control electromagnetic valve 11, the outlet B1 of the pressure control electromagnetic valve 11 can output different shift pressures under different shift requirements.

The flow control solenoid valve 21 has an inlet A2 and two outlets B2, B3 (or referred to as a first outlet B2 and a second outlet B3), the inlet A2 of the flow control solenoid valve 21 is connected to the outlet B1 of the pressure control solenoid valve 11, and the two outlets B2, B3 of the flow control solenoid valve 21 are connected to the first gear switching valve 41, the second gear switching valve 42, the third gear switching valve 43, and the fourth gear switching valve 44, so that the pressure oil output from the two outlets B2, B3 of the flow control solenoid valve 21 can push the first shift cylinder 51 to perform a shift operation via the first gear switching valve 41, push the second shift cylinder 52 to perform a shift operation via the second gear switching valve 42, or push the third shift cylinder 53 to perform a shift operation via the third gear switching valve 43, and push the fourth shift cylinder 54 to perform a shift operation via the fourth gear switching valve 44. Specifically, the flow control solenoid valve 21 is switchable between a first operating position, in which the inlet A2 of the flow control solenoid valve 21 communicates with one of the two outlets B2, B3 of the flow control solenoid valve 21, and a second operating position, in which the flow control solenoid valve 21 is in the first operating position; when the flow control solenoid valve 21 is in the second operating position, the inlet A2 of the flow control solenoid valve 21 communicates with the other of the two outlets B2, B3 of the flow control solenoid valve 21. In the present embodiment, when the flow control solenoid valve 21 is in the first operating position (right position as shown in fig. 1), the inlet A2 of the flow control solenoid valve 21 communicates with the first outlet B2 of the flow control solenoid valve 21; when the flow control solenoid valve 21 is switched to the second operating position (left position as viewed in fig. 1), the inlet A2 of the flow control solenoid valve 21 communicates with the second outlet B3 of the flow control solenoid valve 21. That is, by changing the operation position of the flow control solenoid valve 21, the pressure oil can be selectively introduced from the inlet A2 to one of the two outlets B2, B3.

At present, most technical schemes for realizing hydraulic gear shifting control mainly adopt pressure control, and the moving speed of a gear shifting actuating mechanism (namely a gear shifting oil cylinder) cannot be accurately controlled so as to realize accurate control in the gear shifting process. In order to make the hydraulic system control the gear shifting process more accurately on the basis of realizing the gear shifting control, in this embodiment, the flow control electromagnetic valve 21 is a slide valve type flow control proportional electromagnetic valve. Therefore, when the flow control electromagnetic valve 21 works, the spool of the flow control electromagnetic valve 21 can regulate and control the output flows of the two outlets B2 and B3 to a certain extent under the combined action of the electromagnetic force and the spring load force. That is, the flow control electromagnetic valve 21 can change the valve opening of the flow control electromagnetic valve 21 at the current working position by adjusting the current value input to the electromagnet of the flow control electromagnetic valve 21 at each working position (left or right), so as to adjust the output flow of the two outlets B2 and B3 of the flow control electromagnetic valve 21, and further control the moving rate of the shift cylinder, so as to realize the accurate control of the shift process.

The first switching solenoid valve 31 has an inlet A3 and an outlet B4, the second switching solenoid valve 32 has an inlet A4 and an outlet B5, the third switching solenoid valve 33 has an inlet A5 and an outlet B6, and the fourth switching solenoid valve 34 has an inlet A6 and an outlet B7. The first position switching valve 41 has two inlets A7, A8, two outlets B8, B9 and a control terminal C1. The second position switching valve 42 has two inlets A9, a10, two outlets B10, B11 and one control end C2. The third position switching valve 43 has two inlets a11, a12, two outlets B12, B13 and one control end C3. The fourth-gear switching valve 44 has two inlets a13, a14, two outlets B14, B15, and one control terminal C4.

An inlet A3 of the first switching solenoid valve 31 is connected to the main oil passage 10, and an outlet B4 of the first switching solenoid valve 31 is connected to a control terminal C1 of the first-stage switching valve 41. An inlet A4 of the second switching solenoid valve 32 is connected to the main oil passage 10, and an outlet B5 of the second switching solenoid valve 32 is connected to a control terminal C2 of the second gear switching valve 42. An inlet A5 of the third switching solenoid valve 33 is connected to the main oil passage 10, and an outlet B6 of the third switching solenoid valve 33 is connected to a control terminal C3 of the third gear switching valve 43. An inlet A6 of the fourth switching solenoid valve 34 is connected to the main oil passage 10, and an outlet B7 of the fourth switching solenoid valve 34 is connected to a control terminal C4 of the fourth gear switching valve 44.

The two inlets A7, A8 of the first position switching valve 41 are connected to the two outlets B2, B3 of the flow control solenoid valve 21, respectively. The two inlets A9, a10 of the second-gear switching valve 42 are connected to the two outlets B2, B3 of the flow control solenoid valve 21, respectively. The two inlets a11, a12 of the third position switching valve 43 are connected to the two outlets B2, B3 of the flow control solenoid valve 21, respectively. The two inlets a13, a14 of the fourth-gear switching valve 44 are connected to the two outlets B2, B3 of the flow control solenoid valve 21, respectively.

The two outlets B8, B9 of the first shift switch valve 41 are connected to two oil chambers of the first shift cylinder 51, respectively. The two outlets B10, B11 of the second shift switching valve 42 are connected to the two oil chambers of the second shift cylinder 52, respectively. The two outlets B12, B13 of the third shift switch valve 43 are connected to the two oil chambers of the third shift cylinder 53, respectively. The two outlets B14, B15 of the fourth gear switching valve 44 are connected to two oil chambers of the fourth shift cylinder 54, respectively.

The first switching solenoid valve 31 is switchable between a cut-off operating position and a cut-on operating position, and when the first switching solenoid valve 31 is in the cut-off operating position (right position as shown in fig. 1), the inlet A3 of the first switching solenoid valve 31 is disconnected from the outlet B4 of the first switching solenoid valve 31; when the first switching solenoid valve 31 is in the conducting operating position (the left position shown in fig. 1), the inlet A3 of the first switching solenoid valve 31 is communicated with the outlet B4 of the first switching solenoid valve 31, and at this time, the pressure oil from the main oil passage 10 is applied to the control end C1 of the first gear switching valve 41 via the first switching solenoid valve 31 to push the first gear switching valve 41 to perform the reversing.

The second on-off solenoid valve 32 is switchable between an off operating position and an on operating position, and when the second on-off solenoid valve 32 is in the off operating position (right position as shown in fig. 1), the inlet A4 of the second on-off solenoid valve 32 is disconnected from the outlet B5 of the second on-off solenoid valve 32; when the second switching solenoid valve 32 is in the conducting operating position (the left position shown in fig. 1), the inlet A4 of the second switching solenoid valve 32 is communicated with the outlet B5 of the second switching solenoid valve 32, and at this time, the pressure oil from the main oil passage 10 is applied to the control end C2 of the second-gear switching valve 42 via the second switching solenoid valve 32 to push the second-gear switching valve 42 to perform the reversing operation.

The third switching solenoid valve 33 is switchable between a cut-off operating position and a conducting operating position, and when the third switching solenoid valve 33 is in the cut-off operating position (right position as shown in fig. 1), the inlet A5 of the third switching solenoid valve 33 is disconnected from the outlet B6 of the third switching solenoid valve 33; when the third switching solenoid valve 33 is in the conducting operating position (left position as shown in fig. 1), the inlet A5 of the third switching solenoid valve 33 communicates with the outlet B6 of the third switching solenoid valve 33, and at this time, the pressure oil from the main oil passage 10 is applied to the control end C3 of the third gear switching valve 43 via the third switching solenoid valve 33 to push the third gear switching valve 43 to reverse.

The fourth switch solenoid valve 34 is switchable between an off operating position and an on operating position, and when the fourth switch solenoid valve 34 is in the off operating position (right position as shown in fig. 1), the inlet A6 of the fourth switch solenoid valve 34 is disconnected from the outlet B7 of the fourth switch solenoid valve 34; when the fourth switching solenoid valve 34 is in the on operating position (left position as shown in fig. 1), the inlet A6 of the fourth switching solenoid valve 34 communicates with the outlet B7 of the fourth switching solenoid valve 34, and at this time, the pressure oil from the main oil passage 10 is applied to the control terminal C4 of the fourth gear switching valve 44 via the fourth switching solenoid valve 34 to push the fourth gear switching valve 44 to reverse.

In the present embodiment, the first-gear switching valve 41 is a pilot operated directional control valve of a spool type. The first gear switch valve 41 can be switched between a first working position and a second working position, when the first gear switch valve 41 is in the first working position (right position as shown in fig. 1), two inlets A7 and A8 of the first gear switch valve 41 are respectively disconnected with two outlets B8 and B9 of the first gear switch valve 41, and at the moment, two outlets B8 and B9 of the first gear switch valve 41 are both communicated with the oil tank; when the first switching solenoid valve 31 is in the conducting operating position and the pressure oil from the main oil passage 10 is applied to the control end C1 of the first gear switch valve 41 through the first switching solenoid valve 31 to push the first gear switch valve 41 to switch to the second operating position (the left position as shown in fig. 1), the two inlets A7, A8 of the first gear switch valve 41 are respectively communicated with the two outlets B8, B9 of the first gear switch valve 41, and at this time, the pressure oil from the flow control solenoid valve 21 can enter the first shift cylinder 51 through the first gear switch valve 41 to push the first shift cylinder 51 to perform the shifting operation.

In this embodiment, the second-gear switching valve 42 is a pilot operated directional control valve of a spool type. The second-gear switching valve 42 can be switched between a first working position and a second working position, when the second-gear switching valve 42 is in the first working position (right position as shown in fig. 1), two inlets A9 and a10 of the second-gear switching valve 42 are respectively disconnected with two outlets B10 and B11 of the second-gear switching valve 42, and at this time, two outlets B10 and B11 of the second-gear switching valve 42 are both communicated with the oil tank; when the second switching solenoid valve 32 is in the conducting operating position, and the pressure oil from the main oil passage 10 is applied to the control end C2 of the second position switch valve 42 via the second switching solenoid valve 32 to push the second position switch valve 42 to switch to the second operating position (the left position as shown in fig. 1), the two inlets A9, a10 of the second position switch valve 42 are respectively communicated with the two outlets B10, B11 of the second position switch valve 42, and the pressure oil from this moment can enter the second shift cylinder 52 through the second position switch valve 42 to push the second shift cylinder 52 to perform a shifting operation.

In this embodiment, the third-gear switching valve 43 is a pilot operated directional control valve of a spool type. The third position switch valve 43 can be switched between a first working position and a second working position, when the third position switch valve 43 is in the first working position (right position as shown in fig. 1), two inlets a11 and a12 of the third position switch valve 43 are respectively disconnected with two outlets B12 and B13 of the third position switch valve 43, and at this time, two outlets B12 and B13 of the third position switch valve 43 are both communicated with the oil tank; when the third switching solenoid valve 33 is in the conducting operating position and the pressure oil from the main oil passage 10 is applied to the control end C3 of the third position switch valve 43 through the third switching solenoid valve 33 to push the third position switch valve 43 to switch to the second operating position (the left position as shown in fig. 1), the two inlets a11, a12 of the third position switch valve 43 are respectively communicated with the two outlets B12, B13 of the third position switch valve 43, and the pressure oil from the flow control solenoid valve 21 can enter the third shift cylinder 53 through the third position switch valve 43 to push the third shift cylinder 53 to perform a shifting operation.

In the present embodiment, the fourth-gear switching valve 44 is a pilot operated directional control valve of a spool type. The fourth-gear switching valve 44 is switchable between a first operating position and a second operating position, when the fourth-gear switching valve 44 is in the first operating position (the right position shown in fig. 1), two inlets a13 and a14 of the fourth-gear switching valve 44 are respectively disconnected from two outlets B14 and B15 of the fourth-gear switching valve 44, and at this time, two outlets B14 and B15 of the fourth-gear switching valve 44 are both connected to the oil tank; when the fourth switching solenoid valve 34 is in the on operating position and the pressure oil from the main oil path 10 is applied to the control end C4 of the fourth position switch valve 44 through the fourth switching solenoid valve 34 to push the fourth position switch valve 44 to switch to the second operating position (the left position as shown in fig. 1), the two inlets a13, a14 of the fourth position switch valve 44 are respectively communicated with the two outlets B14, B15 of the fourth position switch valve 44, and the pressure oil from the fourth position switch valve 44 can enter the fourth shift cylinder 54 to push the fourth shift cylinder 54 to perform a shifting operation.

As described above, the outlet of the pressure control solenoid valve 11 is connected to the inlet of the flow control solenoid valve 21, the outlet of the flow control solenoid valve 21 is connected to the inlet of the first-stage switching valve 41, the inlet of the second-stage switching valve 42, the inlet of the third-stage switching valve 43, and the inlet of the fourth-stage switching valve 44, the outlet of the first-stage switching valve 41 is connected to the oil chamber of the first shift cylinder 51, the outlet of the second-stage switching valve 42 is connected to the oil chamber of the second shift cylinder 52, the outlet of the third-stage switching valve 43 is connected to the oil chamber of the third shift cylinder 53, the outlet of the fourth-stage switching valve 44 is connected to the oil chamber of the fourth shift cylinder 54, the outlet of the first switching solenoid valve 31 is connected to the control terminal of the first-stage switching valve 41, the first-stage switching valve 41 is controlled by the first-switching solenoid valve 31 to perform switching, the outlet of the second-stage switching valve 32 is connected to the control terminal of the second-stage switching valve 42, the second-stage switching valve 42 is controlled by the second-switching valve 32, the third-switching valve 33 is connected to the inlet of the fourth-switching valve 33, the fourth-switching valve 33 is connected to the outlet of the fourth-switching solenoid valve 33, and the fourth-stage switching valve 33, the fourth-stage switching valve 33 is connected to the fourth-control solenoid valve 33, and the fourth-control solenoid valve 33 is connected to the fourth-control solenoid valve 34, and the fourth-control solenoid valve 33 of the fourth-control solenoid valve 32.

The pressure control solenoid valve 11 can adjust the inlet pressure of the flow control solenoid valve 21, the flow control solenoid valve 21 can accurately control the outlet pressure and flow according to the inlet pressure, and the flow control solenoid valve 21 can also perform reversing control of an oil path to change a pressure oil port and an oil drain port. The adjustable inlet pressure can accurately control the pressure and flow of the outlet according to the inlet pressure, and meanwhile, the reversing control of the oil way can be carried out to change a pressure oil port and an oil drainage port. The first switching solenoid valve 31 can control the opening and closing of the first gear switching valve 41, so that the first shift cylinder 51 is connected with the pressure port and the oil drainage port of the flow control solenoid valve 21; the second switching solenoid valve 32 can control the second gear switching valve 42 to open and close, so that the second shift cylinder 52 is connected with the pressure port and the oil drainage port of the flow control solenoid valve 21; the third switching solenoid valve 33 can control the opening and closing of the third shift switching valve 43, so that the third shift cylinder 53 is connected to the pressure port and the drain port of the flow control solenoid valve 21; the fourth switching solenoid valve 34 controls the opening and closing of the fourth shift switching valve 44, and connects the fourth shift cylinder 54 to the pressure port and the drain port of the flow control solenoid valve 21.

Therefore, by controlling the pressure control solenoid valve 11, the flow control solenoid valve 21, and the first switching solenoid valve 31, the first shift cylinder 51 can be moved at a certain rate between the first position and the second position. Assuming that the first shift cylinder 51 is used to control reverse and 6 gears, when the pressure control solenoid valve 11 and the first switch solenoid valve 31 are turned on and the flow control solenoid valve 21 is in the first operating position (right position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the first outlet B2 of the flow control solenoid valve 21 after pressure and flow regulation is performed by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the first shift switch valve 41 is turned to the on position under the control of the first switch solenoid valve 31, the pressure oil in the first outlet B2 of the flow control solenoid valve 21 will reach the first outlet B8 through the first inlet A7 of the first shift switch valve 41 and then reach the left chamber of the first shift cylinder 51, pushing the first shift cylinder 51 to move right and to engage 6 gears; when the pressure control solenoid valve 11 and the first switching solenoid valve 31 are conducted and the flow control solenoid valve 21 is in the second working position (the left position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the second outlet B3 of the flow control solenoid valve 21 after being subjected to pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the first shift switch valve 41 is switched to the conducting position under the control of the first switching solenoid valve 31, the pressure oil in the second outlet B3 of the flow control solenoid valve 21 reaches the second outlet B9 through the second inlet A8 of the first shift switch valve 41 and then reaches the right chamber of the first shift cylinder 51, so as to push the first shift cylinder 51 to move left and engage the reverse gear.

The second shift cylinder 52 is caused to move at a certain rate between the first position and the second position by controlling the pressure control solenoid valve 11, the flow control solenoid valve 21, and the second on-off solenoid valve 32. Assuming that the second shift cylinder 52 is used to control the 7 th gear and the 3 rd gear, when the pressure control solenoid valve 11 and the second switching solenoid valve 32 are turned on and the flow control solenoid valve 21 is in the first operating position (right position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the first outlet B2 of the flow control solenoid valve 21 after pressure and flow regulation is performed by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the second shift switch valve 42 has been turned to the on position under the control of the second switching solenoid valve 32, the pressure oil in the first outlet B2 of the flow control solenoid valve 21 will reach the first outlet B10 through the first inlet A9 of the second shift switch valve 42 and then reach the left chamber of the second shift cylinder 52, pushing the second shift cylinder 52 to move to the right and engage the 3 rd gear; when the pressure control solenoid valve 11 and the second switching solenoid valve 32 are turned on and the flow control solenoid valve 21 is in the second operating position (left position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the second outlet B3 of the flow control solenoid valve 21 after being subjected to pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the second shift switch valve 42 has been switched to the on position under the control of the second switching solenoid valve 32, the pressure oil in the second outlet B3 of the flow control solenoid valve 21 will reach the second outlet B11 via the second inlet a10 of the second shift switch valve 42 and then reach the right chamber of the second shift cylinder 52, pushing the second shift cylinder 52 to the left and engaging 7 th gear.

By controlling the pressure control solenoid valve 11, the flow control solenoid valve 21, and the third on/off solenoid valve 33, the third shift cylinder 53 can be moved at a certain rate between the first position and the second position. Assuming that the third shift cylinder 53 is used to control the 2 nd and 4 th gears, when the pressure control solenoid valve 11 and the third switching solenoid valve 33 are turned on and the flow control solenoid valve 21 is in the first operating position (right position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the first outlet B2 of the flow control solenoid valve 21 after pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the third shift switch valve 43 has been turned to the on position under the control of the third switching solenoid valve 33, the pressure oil in the first outlet B2 of the flow control solenoid valve 21 will reach the first outlet B12 by the first inlet a11 of the third shift switch valve 43 and then reach the left chamber of the third shift cylinder 53, pushing the third shift cylinder 53 to right and engaging the 4 th gear; when the pressure control solenoid valve 11 and the third switching solenoid valve 33 are turned on and the flow control solenoid valve 21 is in the second operating position (the left position as shown in fig. 1), the pressure oil from the main oil passage 10 is subjected to pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21 and then reaches the second outlet B3 of the flow control solenoid valve 21, and since the third shift switch valve 43 has been switched to the on position under the control of the third switching solenoid valve 33, the pressure oil in the second outlet B3 of the flow control solenoid valve 21 will reach the second outlet B13 via the second inlet a12 of the third shift switch valve 43 and then reach the right chamber of the third shift cylinder 53, pushing the third shift cylinder 53 to the left and engaging 2 nd gear.

By controlling the pressure control solenoid valve 11, the flow control solenoid valve 21, and the fourth switch solenoid valve 34, the fourth shift cylinder 54 can be moved between the first position and the second position at a certain rate. Assuming that the fourth shift cylinder 54 is used for controlling 5 th and 1 st gears in the present embodiment, when the pressure control solenoid valve 11 and the fourth switch solenoid valve 34 are turned on and the flow control solenoid valve 21 is in the first operating position (right position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the first outlet B2 of the flow control solenoid valve 21 after being subjected to pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the fourth shift switch valve 44 has been switched to the on position under the control of the fourth switch solenoid valve 34, the pressure oil in the first outlet B2 of the flow control solenoid valve 21 will reach the first outlet B14 through the first inlet a13 of the fourth shift switch valve 44 and then reach the left chamber of the fourth shift cylinder 54, pushing the fourth shift cylinder 54 to the right and engaging 1 st gear; when the pressure control solenoid valve 11 and the fourth switch solenoid valve 34 are turned on and the flow control solenoid valve 21 is in the second operating position (left position as shown in fig. 1), the pressure oil from the main oil passage 10 reaches the second outlet B3 of the flow control solenoid valve 21 after being subjected to pressure and flow regulation by the pressure control solenoid valve 11 and the flow control solenoid valve 21, and since the fourth shift switch valve 44 has been switched to the on position under the control of the fourth switch solenoid valve 34, the pressure oil in the second outlet B3 of the flow control solenoid valve 21 will reach the second outlet B15 via the second inlet a14 of the fourth shift switch valve 44 and then reach the right chamber of the fourth shift cylinder 54, pushing the fourth shift cylinder 54 to move left and put into 5 steps.

Therefore, in the embodiment of the invention, the combination of the electromagnetic valve and the slide valve is adopted as few as possible, the gear shifting control of the automatic transmission with eight gears is realized, and the pressure control electromagnetic valve 11 and the flow control electromagnetic valve 21 are used for realizing the double control of the gear shifting pressure and the flow on the basis of realizing the gear shifting control of the transmission, so that the hydraulic system can control the gear shifting process more accurately, the accurate control of the gear shifting process can be realized better, the use of the slide valve is reduced, the system is more portable, and the control logic is simpler.

The hydraulic shift control system of the present embodiment further includes a main pump 61, a sub-pump 62, and an oil tank 63. The main pump 61 and the sub pump 62 draw oil from the oil tank 63 via the oil suction filter 64, thereby supplying pressure oil required for operation to the main oil passage 10 of the hydraulic shift control system. In the present embodiment, the main pump 61 is directly driven by the engine of the automobile, the sub-pump 62 is driven by the motor, and the sub-pump 62 can assist the main pump 61 when the oil delivery amount of the main pump 61 is insufficient, on the one hand, and can ensure the supply of the pressure oil in the system when the engine and therefore the main pump 61 are stopped, on the other hand. Tank symbols are used at various locations in fig. 1, and are understood to be communicated to the tank 63 via associated lines.

To prevent the reverse flow of the oil, check valves 65 are connected to outlets of the main pump 61 and the sub-pump 62. In order to control the maximum pressure in the system, a system relief valve 66 is further connected to the outlet of the main pump 61, and the system relief valve 66 may be a safety relief valve or a check valve, in this embodiment, the system relief valve 66 is a check valve and is connected between the outlet of the main pump 61 and the oil tank 63, the maximum pressure allowed in the system is set through the check valve, and when the pressure in the system exceeds the maximum pressure, the check valve is opened to release oil.

The hydraulic shift control system of the present embodiment further includes a first clutch solenoid valve 71, a second clutch solenoid valve 72, and a clutch relief valve 73.

The first clutch solenoid valve 71 is used to control engagement or disengagement of the first clutch T1. The first clutch solenoid valve 71 has an inlet a15 and an outlet B16, the inlet a15 of the first clutch solenoid valve 71 is connected to the main oil passage 10, and the outlet B16 of the first clutch solenoid valve 71 is connected to the clutch relief valve 73. The first clutch solenoid valve 71 is switchable between a cut-off operating position and a cut-on operating position, and when the first clutch solenoid valve 71 is in the cut-off operating position (right position as shown in fig. 1), the inlet a15 of the first clutch solenoid valve 71 is disconnected from the outlet B16 of the first clutch solenoid valve 71, and the outlet B16 of the first clutch solenoid valve 71 is communicated to the oil tank 63, at which time the first clutch T1 is disengaged; when the first clutch solenoid valve 71 is in the conducting operating position (left position as viewed in fig. 1), the inlet a15 of the first clutch solenoid valve 71 communicates with the outlet B16 of the first clutch solenoid valve 71, and at this time, the pressure oil from the main oil passage 10 drives the first clutch T1 to engage via the first clutch solenoid valve 71 and the clutch relief valve 73.

The second clutch solenoid valve 72 is used to control the engagement or disengagement of the second clutch T2. The second clutch solenoid valve 72 has an inlet a16 and an outlet B17, the inlet a16 of the second clutch solenoid valve 72 is connected to the main oil passage 10, and the outlet B17 of the second clutch solenoid valve 72 is connected to the clutch relief valve 73. The second clutch solenoid valve 72 is switchable between a cut-off operating position and a cut-on operating position, and when the second clutch solenoid valve 72 is in the cut-off operating position (right position as shown in fig. 1), the inlet a16 of the second clutch solenoid valve 72 is disconnected from the outlet B17 of the second clutch solenoid valve 72, and the outlet B17 of the second clutch solenoid valve 72 is communicated to the oil tank 63, at which time the second clutch T2 is disengaged; when the second clutch solenoid valve 72 is in the conducting operating position (left position as shown in fig. 1), the inlet a16 of the second clutch solenoid valve 72 communicates with the outlet B17 of the second clutch solenoid valve 72, and at this time, the pressure oil from the main oil passage 10 drives the second clutch T2 to engage via the second clutch solenoid valve 72 and the clutch relief valve 73.

The clutch relief valve 73 is configured to cut off the oil passage to the clutches T1, T2 when the clutches T1, T2 fail. The clutch relief valve 73 has two inlet ports a17, a18, two outlet ports B18, B19 and one control port C5, the two inlet ports a17, a18 of the clutch relief valve 73 are connected to the outlet port B16 of the first clutch solenoid valve 71 and the outlet port B17 of the second clutch solenoid valve 72, respectively, the two outlet ports B18, B19 of the clutch relief valve 73 are connected to the first clutch T1 and the second clutch T2, respectively, the outlet ports of two of the first to fourth switching solenoid valves 31, 32, 33, 34 are simultaneously connected to the control port C5 of the clutch relief valve 73, and in the present embodiment, the outlet port B4 of the first switching solenoid valve 31 and the outlet port B7 of the fourth switching solenoid valve 34 are simultaneously connected to the control port C5 of the clutch relief valve 73. The clutch relief valve 73 is switchable between an open position and a closed position, and when the clutch relief valve 73 is in the open position (left position as shown in fig. 1), the two inlets a17, a18 of the clutch relief valve 73 are respectively communicated with the two outlets B18, B19 of the clutch relief valve 73, at this time, the engagement or disengagement of the first clutch T1 can be realized by controlling the reversing operation of the first clutch solenoid valve 71, and the engagement or disengagement of the second clutch T2 can be realized by controlling the reversing operation of the second clutch solenoid valve 72; when the clutches T1, T2 are out of order, the first switch solenoid valve 31 and the fourth switch solenoid valve 34 are opened at the same time, so that the pressure oil output by the first switch solenoid valve 31 and the fourth switch solenoid valve 34 is simultaneously applied to the control end C5 of the clutch relief valve 73, and the clutch relief valve 73 is pushed to switch from the open position to the closed position (the right position as shown in fig. 1), at this time, the two inlet ports a17, a18 of the clutch relief valve 73 are respectively disconnected from the two outlet ports B18, B19 of the clutch relief valve 73, so that the oil passages to the clutches T1, T2 are cut off, and at this time, the first clutch T1 and the second clutch T2 are unloaded by the clutch relief valve 73.

The hydraulic shift control system of the present embodiment further includes a fifth switching solenoid valve 35, a parking control valve 81, and a parking cylinder 82. The fifth switching solenoid valve 35 has an inlet a19 and an outlet B20. The inlet a19 of the fifth switching solenoid valve 35 is connected to the main oil passage 10, and the outlet B20 of the fifth switching solenoid valve 35 is connected to the control port C6 of the parking control valve 81. The fifth switching solenoid valve 35 is switchable between an off operating position and an on operating position, and when the fifth switching solenoid valve 35 is in the off operating position (the right position as viewed in fig. 1), the inlet a19 of the fifth switching solenoid valve 35 is disconnected from the outlet B20 of the fifth switching solenoid valve 35; when the fifth switching solenoid valve 35 is in the conducting operating position (left position as shown in fig. 1), the inlet a19 of the fifth switching solenoid valve 35 communicates with the outlet B20 of the fifth switching solenoid valve 35, and at this time, the pressure oil from the main oil passage 10 is applied to the control end C6 of the parking control valve 81 via the fifth switching solenoid valve 35 to push the parking control valve 81 to perform the reversing.

In this embodiment, the parking control valve 81 is a slide valve type pilot operated directional control valve. The parking control valve 81 has an inlet a20, two outlets B21, B22, and a control end C6, the inlet a20 of the parking control valve 81 is connected to the main oil passage 10, the two outlets B21, B22 of the parking control valve 81 are respectively connected to the two oil chambers of the parking cylinder 82, and the control end C6 of the parking control valve 81 is connected to the outlet B20 of the fifth on-off solenoid valve 35. The parking control valve 81 is switchable between a first operating position and a second operating position, when the parking control valve 81 is in the first operating position (right position as shown in fig. 1), the inlet a20 of the parking control valve 81 is communicated with the first outlet B21 of the parking control valve 81, the second outlet B22 of the parking control valve 81 is communicated with the oil tank 63, and at this time, pressure oil from the main oil passage 10 enters one oil chamber of the parking cylinder 82 through the parking control valve 81 to push the parking cylinder 82 to move to one side; when the fifth on-off solenoid valve 35 is in the conducting operating position, and the pressure oil from the main oil passage 10 is applied to the control end C6 of the parking control valve 81 through the fifth on-off solenoid valve 35 to push the parking control valve 81 to switch to the second operating position (the left position shown in fig. 1), the inlet a20 of the parking control valve 81 is communicated with the second outlet B22 of the parking control valve 81, the first outlet B21 of the parking control valve 81 is communicated with the oil tank 63, and at this time, the pressure oil from the main oil passage 10 passes through the parking control valve 81 to enter another oil chamber of the parking cylinder 82 to push the parking cylinder 82 to move to the other side. Thus, the automatic parking and unlocking functions of the vehicle are realized by the fifth switching solenoid valve 35, the parking control valve 81, and the parking cylinder 82.

The hydraulic shift control system of the present embodiment further includes a second pressure control solenoid valve 12 and a main oil passage pressure regulating valve 18.

The second pressure control solenoid valve 12 has an inlet a21 and an outlet B23. The main oil pressure regulating valve 18 has an inlet a22, two outlets B24, B25 (or referred to as a first outlet B24 and a second outlet B25), and two control ends C7, C8 (or referred to as a first control end C7 and a second control end C8). The inlet a21 of the second pressure control solenoid valve 12 is connected to the main oil passage 10, the outlet B23 of the second pressure control solenoid valve 12 is connected to the first control end C7 of the main oil passage pressure regulating valve 18, the inlet a22 and the second control end C8 of the main oil passage pressure regulating valve 18 are simultaneously connected to the main oil passage 10, the first outlet B24 of the main oil passage pressure regulating valve 18 is connected to the oil tank 63, and the second outlet B25 of the main oil passage pressure regulating valve 18 is opened to a lubricating and cooling oil passage for lubricating and cooling related elements (such as bearings, gears, clutches, etc.).

In the present embodiment, the second pressure control solenoid valve 12 is a spool-type pressure control proportional solenoid valve, and the pressure at the outlet B23 of the second pressure control solenoid valve 12 is fed back to one end of the second pressure control solenoid valve 12 (fed back to the solenoid end as shown in fig. 1) through an oil passage. Therefore, when the second pressure control solenoid valve 12 is in operation, the spool of the second pressure control solenoid valve 12 can adjust and control the output pressure of the outlet B23 under the combined action of the electromagnetic force, the spring load force and the hydraulic feedback force, so as to change the acting force applied to the first control end C7 of the main oil path pressure regulating valve 18, and gradually switch the main oil path pressure regulating valve 18 from the closed position to the open position, thereby adjusting the oil pressure in the main oil path 10, and simultaneously, the redundant oil in the main oil path 10 can be delivered to the lubricating and cooling oil path through the main oil path pressure regulating valve 18, so as to meet the requirements of oil cooling and lubrication of related elements.

In the present embodiment, the main oil passage pressure regulating valve 18 has three operating positions. When the output pressure at the outlet B23 of the second pressure control solenoid valve 12 is greater, the force acting on the first control end C7 of the main oil passage pressure regulating valve 18 is also greater, and at this time, the main oil passage pressure regulating valve 18 is in the first operating position (the right position as viewed in fig. 1), and the inlet a22 of the main oil passage pressure regulating valve 18 is disconnected from both outlets B24, B25 of the main oil passage pressure regulating valve 18; as the output pressure at the outlet B23 of the second pressure control solenoid valve 12 decreases, the force acting on the first control end C7 of the main oil pressure regulator valve 18 also decreases, and the force acting on the second control end C8 of the main oil pressure regulator valve 18 at this time will be greater than the force acting on the first control end C7, pushing the main oil pressure regulator valve 18 to switch to the second operating position (the neutral position shown in fig. 1), and the inlet a22 of the main oil pressure regulator valve 18 at this time being in communication with the second outlet B25 of the main oil pressure regulator valve 18, and oil can be led to the lubricating and cooling oil circuit via the main oil pressure regulator valve 18; as the output pressure at the outlet B23 of the second pressure control solenoid valve 12 continues to decrease, the main line pressure regulator valve 18 will switch to a third operating position (left position as viewed in fig. 1), at which point the inlet a22 of the main line pressure regulator valve 18 communicates with both outlets B24, B25 of the main line pressure regulator valve 18, a portion of the oil may be directed to the lubricating cooling line via the main line pressure regulator valve 18, and another portion of the oil may be returned to the tank 63 via the main line pressure regulator valve 18.

The hydraulic shift control system of the present embodiment further includes a third pressure control solenoid valve 13. The third pressure control solenoid valve 13 has an inlet a23 and an outlet B26. An inlet a23 of the third pressure control solenoid valve 13 is connected to the main oil passage 10, and an outlet B26 of the third pressure control solenoid valve 13 is connected to the lubricating and cooling oil passage.

In this embodiment, the third pressure control solenoid valve 13 is a slide valve type pressure control proportional solenoid valve, and the pressure at the outlet B26 of the third pressure control solenoid valve 13 is fed back to one end of the third pressure control solenoid valve 13 through an oil passage (fed back to the solenoid end in fig. 1). Therefore, when the third pressure control solenoid valve 13 is in operation, the spool of the third pressure control solenoid valve 13 can regulate and control the output pressure of the outlet B26 under the combined action of the electromagnetic force, the spring load force and the hydraulic feedback force.

[ second embodiment ]

Fig. 2 is a schematic structural view of a hydraulic shift control system of a dual clutch automatic transmission according to a second embodiment of the present invention, which is different from the first embodiment in that in the present embodiment, first to fourth switching solenoids 31, 32, 33, 34 are integrated, for example, the first to fourth switching solenoids 31, 32 are integrated into a three-position four-way switching solenoid 36, so that an inlet A3 of the first switching solenoid 31 and an inlet A4 of the second switching solenoid 32 are integrated into an inlet a24 of the three-position four-way switching solenoid 36 and connected to the main oil passage 10, and an outlet B4 of the first switching solenoid 31 and an outlet B5 of the second switching solenoid 32 are two outlets of the three-position four-way switching solenoid 36, respectively; the third switching solenoid valve 33 and the fourth switching solenoid valve 34 are integrated into another three-position four-way switching solenoid valve 37, so that the inlet A5 of the third switching solenoid valve 33 and the inlet A6 of the fourth switching solenoid valve 34 are integrated into one inlet a25 of the three-position four-way switching solenoid valve 37 and connected to the main oil passage 10, and the outlet B6 of the third switching solenoid valve 33 and the outlet B7 of the fourth switching solenoid valve 34 are respectively two outlets of the three-position four-way switching solenoid valve 37.

The first three-position four-way switching solenoid valve 36 can be switched among a cut-off position, a first working position and a second working position, in this embodiment, when the switching solenoid valve 36 is located at the cut-off position (as a middle position shown in fig. 2), the inlet a24 of the switching solenoid valve 36 is not disconnected from the first outlet B4 and the second outlet B5 of the switching solenoid valve 36, and at this time, the first outlet B4 and the second outlet B5 of the switching solenoid valve 36 are communicated with the oil tank; when the on-off solenoid valve 36 is switched to the first working position (the right position shown in fig. 2), the inlet a24 of the on-off solenoid valve 36 is communicated with the first outlet B4 of the on-off solenoid valve 36, and the second outlet B5 of the on-off solenoid valve 36 is communicated to the oil tank; when the on-off solenoid valve 36 is switched to the second operating position (the left position shown in fig. 2), the inlet a24 of the on-off solenoid valve 36 communicates with the second outlet B5 of the on-off solenoid valve 36, and the first outlet B4 of the on-off solenoid valve 36 communicates with the tank. That is, by changing the operation position of the on-off solenoid valve 36, it is possible to selectively guide the pressure oil from the inlet a24 to one of the two outlets B4, B5, and thus the first on-off solenoid valve 31 and the second on-off solenoid valve 32 in the above-described first embodiment can be integrated into one on-off solenoid valve, further reducing the number of spool valves and reducing the cost.

The second three-position four-way switching solenoid valve 37 can be switched among a cut-off position, a first working position and a second working position, in this embodiment, when the switching solenoid valve 37 is located at the cut-off position (as shown in fig. 2 as a middle position), the inlet a24 of the switching solenoid valve 37 is disconnected from the first outlet B6 and the second outlet B7 of the switching solenoid valve 37, and at this time, the first outlet B6 and the second outlet B7 of the switching solenoid valve 37 are communicated with the oil tank; when the on-off solenoid valve 37 is switched to the first working position (the right position as shown in fig. 2), the inlet a24 of the on-off solenoid valve 37 is communicated with the first outlet B6 of the on-off solenoid valve 37, and the second outlet B7 of the on-off solenoid valve 37 is communicated to the oil tank; when the on-off solenoid valve 37 is switched to the second operating position (the left position as viewed in fig. 2), the inlet a24 of the on-off solenoid valve 37 communicates with the second outlet B7 of the on-off solenoid valve 37, and the first outlet B6 of the on-off solenoid valve 37 communicates with the tank. That is, by changing the operation position of the on-off solenoid valve 37, it is possible to selectively guide the pressure oil from the inlet a24 to one of the two outlets B6, B7, and thus it is possible to integrate the third on-off solenoid valve 33 and the fourth on-off solenoid valve 34 in the above-described first embodiment into one on-off solenoid valve, further reducing the number of spool valves and reducing the cost.

Other structures and working principles of this embodiment can be referred to the first embodiment, and are not described herein again.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (8)

1. A hydraulic shift control system of a dual clutch automatic transmission, characterized in that the hydraulic shift control system includes a pressure control solenoid valve (11), a flow control solenoid valve (21), a first on-off solenoid valve (31), a second on-off solenoid valve (32), a third on-off solenoid valve (33), a fourth on-off solenoid valve (34), a first shift switching valve (41), a second shift switching valve (42), a third shift switching valve (43), a fourth shift switching valve (44), a first shift cylinder (51), a second shift cylinder (52), a third shift cylinder (53) and a fourth shift cylinder (54), wherein an outlet of the pressure control solenoid valve (11) is connected to an inlet of the flow control solenoid valve (21), an outlet of the flow control solenoid valve (21) is connected to an inlet of the first shift switching valve (41), an inlet of the second shift cylinder (42), an inlet of the third shift switching valve (43) and an inlet of the fourth shift cylinder (44), an outlet of the first shift switching valve (41) is connected to an outlet of the second shift cylinder (51), an outlet of the fourth shift cylinder (44) is connected to an outlet of the fourth shift cylinder (52), an outlet of the second shift cylinder (51) is connected to an outlet of the second shift cylinder (52), an outlet of the first switching solenoid valve (31) is connected with a control end of the first gear switching valve (41), the first gear switching valve (41) is controlled by the first switching solenoid valve (31) to perform reversing, an outlet of the second switching solenoid valve (32) is connected with a control end of the second gear switching valve (42), the second gear switching valve (42) is controlled by the second switching solenoid valve (32) to perform reversing, an outlet of the third switching solenoid valve (33) is connected with a control end of the third gear switching valve (43), the third gear switching valve (43) is controlled by the third switching solenoid valve (33) to perform reversing, an outlet of the fourth switching solenoid valve (34) is connected with a control end of the fourth gear switching valve (44), the fourth gear switching valve (44) is controlled by the fourth switching solenoid valve (34) to perform reversing, an inlet of the pressure control solenoid valve (11), an inlet of the first switching solenoid valve (31), an inlet of the second switching solenoid valve (32), and an inlet of the fourth switching solenoid valve (10) are connected with an oil path;

the hydraulic shift control system further includes a second pressure control solenoid valve (12) and a main oil passage pressure regulating valve (18), the second pressure control solenoid valve (12) having an inlet (a 21) and an outlet (B23), the main oil passage pressure regulating valve (18) having an inlet (a 22), two outlets (B24, B25) and two control ends (C7, C8), the inlet (a 21) of the second pressure control solenoid valve (12) being connected to the main oil passage (10), the outlet (B23) of the second pressure control solenoid valve (12) being connected to the first control end (C7) of the main oil passage pressure regulating valve (18), the inlet (a 22) and the second control end (C8) of the main oil passage pressure regulating valve (18) being simultaneously connected to the main oil passage (10), the first outlet (B24) of the main oil passage pressure regulating valve (18) being connected to an oil tank (63), the second outlet (B25) of the main oil passage pressure regulating valve (18) being connected to a lubricating cooling oil passage.

2. The hydraulic shift control system of a dual clutch automatic transmission according to claim 1, characterized in that the pressure control solenoid valve (11) has an inlet (A1) and an outlet (B1), the flow control solenoid valve (21) has an inlet (A2) and two outlets (B2, B3), the inlet (A1) of the pressure control solenoid valve (11) is connected to the main oil passage (10), the outlet (B1) of the pressure control solenoid valve (11) is connected to the inlet (A2) of the flow control solenoid valve (21), and the two outlets (B2, B3) of the flow control solenoid valve (21) are connected to the first gear switching valve (41), the second gear switching valve (42), the third gear switching valve (43), and the fourth gear switching valve (44).

3. The hydraulic shift control system of a dual clutch automatic transmission as set forth in claim 2, characterized in that the flow control solenoid valve (21) is switchable between a first operating position and a second operating position, and when the flow control solenoid valve (21) is in the first operating position, the inlet (A2) of the flow control solenoid valve (21) is communicated with one of the two outlets (B2, B3) of the flow control solenoid valve (21); when the flow control electromagnetic valve (21) is in the second working position, the inlet (A2) of the flow control electromagnetic valve (21) is communicated with the other of the two outlets (B2, B3) of the flow control electromagnetic valve (21).

4. The hydraulic shift control system of a double clutch automatic transmission according to claim 2, characterized in that the first switching solenoid valve (31) has an inlet (A3) and an outlet (B4), the second switching solenoid valve (32) has an inlet (A4) and an outlet (B5), the third switching solenoid valve (33) has an inlet (A5) and an outlet (B6), the fourth switching solenoid valve (34) has an inlet (A6) and an outlet (B7), the first gear switching valve (41) has two inlets (A7, A8), two outlets (B8, B9) and one control terminal (C1), the second gear switching valve (42) has two inlets (A9, a 10), two outlets (B10, B11) and one control terminal (C2), the third gear switching valve (43) has two inlets (a 11, a 12), two outlets (B12, B13) and one control terminal (C3), the fourth gear switching valve (44) has two inlets (a 11, a 12), two outlets (B12, B13) and one control terminal (C3), the fourth switching solenoid valve (32) has two inlets (A6, A4), the first switching solenoid valve (A3), the second switching solenoid valve (34) and the fourth switching valve (34) connected to the inlet (A3), the second switching solenoid valve (14, B6), an outlet (B4) of the first switching electromagnetic valve (31) is connected with a control end (C1) of the first gear switching valve (41), an outlet (B5) of the second switching electromagnetic valve (32) is connected with a control end (C2) of the second gear switching valve (42), an outlet (B6) of the third switching electromagnetic valve (33) is connected with a control end (C3) of the third gear switching valve (43), an outlet (B7) of the fourth switching electromagnetic valve (34) is connected with a control end (C4) of the fourth gear switching valve (44), two inlets (A7, A8) of the first gear switching valve (41) are respectively connected with two outlets (B2, B3) of the flow control electromagnetic valve (21), two inlets (A9, A10) of the second gear switching valve (42) are respectively connected with two outlets (B2, B3) of the flow control electromagnetic valve (21), two inlets (A9, B10) of the third gear switching valve (43) are respectively connected with two outlets (B2, B3) of the flow control electromagnetic valve (21), two inlets (A2, B3) of the first gear switching valve (11) are respectively connected with two outlets (B2, B3) of the flow control electromagnetic valve (13) of the first gear switching valve (11), two outlets (B10, B11) of the second gear switch valve (42) are respectively connected with two oil cavities of the second gear shifting cylinder (52), two outlets (B12, B13) of the third gear switch valve (43) are respectively connected with two oil cavities of the third gear shifting cylinder (53), and two outlets (B14, B15) of the fourth gear switch valve (44) are respectively connected with two oil cavities of the fourth gear shifting cylinder (54).

5. The hydraulic shift control system of a dual clutch automatic transmission according to claim 4, characterized in that the pressure control solenoid valve (11) is a spool type pressure control proportional solenoid valve, the flow control solenoid valve (21) is a spool type flow control proportional solenoid valve, and the first gear switching valve (41), the second gear switching valve (42), the third gear switching valve (43), and the fourth gear switching valve (44) are all spool type pilot operated directional control valves.

6. A hydraulic shift control system of a dual clutch automatic transmission as claimed in claim 4, the hydraulic shift control system further includes a first clutch solenoid valve (71), a second clutch solenoid valve (72), and a clutch relief valve (73), the first clutch solenoid valve (71) having an inlet (A15) and an outlet (B16), the second clutch solenoid valve (72) having an inlet (A16) and an outlet (B17), an inlet (A15) of the first clutch solenoid valve (71) and an inlet (A16) of the second clutch solenoid valve (72) are both connected to the main oil passage (10), the clutch safety valve (73) has two inlets (A17, A18), two outlets (B18, B19) and a control end (C5), the two inlets (A17, A18) of the clutch safety valve (73) are respectively connected with the outlet (B16) of the first clutch electromagnetic valve (71) and the outlet (B17) of the second clutch electromagnetic valve (72), the two outlets (B18, B19) of the clutch safety valve (73) are respectively connected with the first clutch (T1) and the second clutch (T2), outlets of two of the first to fourth switching solenoid valves (31, 32, 33, 34) are simultaneously connected to a control terminal (C5) of the clutch relief valve (73).

7. The hydraulic shift control system of a dual clutch automatic transmission according to claim 4, characterized by further comprising a fifth switching solenoid valve (35), a parking control valve (81) and a parking cylinder (82), the fifth switching solenoid valve (35) having an inlet (A19) and an outlet (B20), the parking control valve (81) having an inlet (A20), two outlets (B21, B22) and a control end (C6), the inlet (A19) of the fifth switching solenoid valve (35) and the inlet (A20) of the parking control valve (81) being connected to the main oil passage (10), the outlet (B20) of the fifth switching solenoid valve (35) being connected to the control end (C6) of the parking control valve (81), the two outlets (B21, B22) of the parking control valve (81) being connected to the two oil chambers of the parking cylinder (82), respectively.

8. The hydraulic shift control system of a dual clutch automatic transmission according to claim 4, characterized in that two of the first to fourth switching solenoids (31, 32, 33, 34) are integrated into one three-position four-way switching solenoid (36), and the other two of the first to fourth switching solenoids (31, 32, 33, 34) are integrated into the other three-position four-way switching solenoid (37).

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