CN116265275A

CN116265275A - Transmission mechanism for hybrid power system and automobile

Info

Publication number: CN116265275A
Application number: CN202111547835.5A
Authority: CN
Inventors: 施国飞; 石兴磊; 凌晓明; 余子林; 张新桂
Original assignee: Guangzhou Automobile Group Co Ltd
Current assignee: Guangzhou Automobile Group Co Ltd
Priority date: 2021-12-16
Filing date: 2021-12-16
Publication date: 2023-06-20

Abstract

The invention provides a transmission mechanism for a hybrid power system and an automobile, the transmission mechanism for the hybrid power system comprises an output gear, an input shaft and a gearbox shell, a clutch is arranged between the output gear and the input shaft, the clutch is provided with an execution piston and a fixed piston which are connected through a release bearing, the fixed piston is arranged in a piston cavity, the piston cavity is arranged on the gearbox shell, and a shell control oil duct communicated with the piston cavity is arranged on the gearbox shell. The invention can simplify the structure of the clutch.

Description

Transmission mechanism for hybrid power system and automobile

Technical Field

The invention relates to the technical field of automobiles, in particular to a transmission mechanism for a hybrid power system and an automobile.

Background

In a hybrid vehicle model, the engagement or disengagement of the clutch may couple or decouple power from the engine and generator to couple or decouple input power to or from the wheels. When the clutch is combined, two modes of mixed motion or direct driving of the engine can be realized, and when the clutch is disconnected, a range extending mode that the engine drives the generator to charge or a pure electric mode that the power of the driving motor is independently output can be realized. If the clutch is applied to a pure electric vehicle, the clutch can be used as a disconnecting device of a P4 rear-drive electric driving mechanism or a disconnecting clutch of one of the double motors. The existing clutch of the hybrid system has complex structure and high cost.

Disclosure of Invention

The invention aims to provide a transmission mechanism for a hybrid power system and an automobile, so as to simplify the structure of a clutch.

The invention provides a transmission mechanism for a hybrid power system, which comprises an output gear and a gearbox shell, wherein a clutch is arranged between the output gear and the gearbox shell, the clutch is provided with an execution piston and a fixed piston which are connected through a release bearing, the fixed piston is arranged in a piston cavity, the piston cavity is arranged on the gearbox shell, and a shell control oil duct communicated with the piston cavity is arranged on the gearbox shell.

Further, the transmission mechanism for the hybrid power system further comprises an inner shell assembly and a return spring, the execution piston is connected with the return spring, the return spring is fixed on a friction plate and a steel sheet set, and the friction plate and the steel sheet set are mounted on the output gear.

Further, an internal spline is arranged on the output gear and is in rigid connection with the external spline of the friction plate and the steel plate set.

Further, a clutch outer housing is fixedly connected to the output gear, and the clutch outer housing accommodates the friction plate and the steel sheet set.

Further, the return spring, the friction plate and the steel sheet set are accommodated in the clutch inner housing assembly, the clutch inner housing assembly is fixed on an input shaft of a transmission mechanism of the hybrid power system, and the clutch inner housing assembly drives the friction plate and the steel sheet set to rotate along with the input shaft.

Further, a generator driving gear is connected to the input shaft, the input shaft and the generator driving gear are fixed into a whole to form an input shaft assembly, and the input shaft assembly is supported on the second shell and the first shell respectively by means of a first bearing and a second bearing.

Further, the input shaft assembly is axially limited through the clutch inner housing assembly, one end of the clutch inner housing assembly is stopped at the output gear, and the other end of the clutch inner housing assembly is abutted against the end face of the second bearing; the output gear is sleeved on the input shaft through a rolling bearing, and the left side is limited by the baffle plate to axially displace.

Further, the right end of the input shaft is connected with a damper, the damper is connected with an engine crankshaft through a flywheel, and an input shaft oil seal for sealing lubricating oil in the gearbox shell is arranged on a radial surface of the input shaft matched with the first shell.

The invention further provides an automobile provided with any one of the transmission mechanisms for the hybrid power system.

According to the invention, the clutch piston is arranged on the static gearbox shell, the control oil duct is optimized from rotary dynamic seal to static seal, the problem of high oil pressure leakage of the hydraulic system caused by the existence of the dynamic seal ring when the clutch is combined is thoroughly solved, the expansion of the hydraulic system to a high-pressure system is facilitated, the system efficiency is more efficient, the dynamic seal ring is eliminated, and the system cost is reduced. The control oil duct of the clutch piston cavity is drilled from the shaft to be a precast oil duct from the gearbox shell, so that the manufacturing process difficulty of the long and thin holes on the shaft which are difficult to process and clean is solved, the processing cost is reduced, and the cleanliness of the oil duct is guaranteed. In addition, the clutch piston is static and does not rotate, and the centrifugal pressure cannot be generated in the oil in the piston cavity, so that a balance cavity is not required to be arranged on the clutch structure to offset the centrifugal pressure in the piston cavity, one part structure is saved, and the structure is more compact and the cost is reduced. The clutch outer shell and the output gear are welded into a whole, or the output gear is forged or powder metallurgy processed to form a spline which is matched and connected with the clutch steel sheet, and the spline and the gear are highly integrated into a part, so that the axial space is more compact.

Drawings

FIG. 1 is a schematic illustration of a transmission for a hybrid powertrain, in accordance with a preferred embodiment of the present invention.

FIG. 2 is a schematic illustration of another transmission for a hybrid powertrain, in accordance with a preferred embodiment of the present invention.

Fig. 3 is an enlarged schematic view of a portion of an output gear according to a preferred embodiment of the present invention.

Fig. 4 is a schematic view of a boss structure of the output gear of fig. 3.

Detailed Description

The following describes in further detail the embodiments of the present invention with reference to the drawings and examples. The following examples are illustrative of the invention and are not intended to limit the scope of the invention.

The invention discloses a transmission scheme and structure with clutch for coupling power of an engine and a generator of a hybrid power system, wherein the transmission scheme controls the closing and opening of a clutch by a clutch control valve of a hydraulic system, and realizes different modes of coupling power of the engine and the generator to a wheel end or decoupling the power of the engine and the generator from the wheel end to cut off power output and the like through connection of a shafting and meshing of a gear set.

Referring to fig. 1, a transmission for a hybrid powertrain is disclosed in accordance with a preferred embodiment of the present invention, which includes an output gear 20, an input shaft 12, and a transmission housing 40, with a clutch 60 disposed between the output gear 20 and the input shaft 12. The clutch 60 has an actuator piston 64 and a stationary piston 66 connected by a release bearing 62, the stationary piston 66 being disposed in a piston chamber 42, the piston chamber 42 being disposed on the transmission housing 40, and a housing control oil passage 44 communicating with the piston chamber 42 being disposed on the transmission housing 40. The invention arranges a clutch with a stationary piston between the output gears of the engine and the intermediate shaft gear for coupling or decoupling engine power to or from the wheel end power. The piston of the clutch is arranged on the static and non-rotating shell, so that the influence of centrifugal pressure generated by the rotation of oil in the piston cavity on the oil pressure-torque characteristic of the control clutch is avoided, and the balance piston is eliminated. The clutch piston cavity control oil duct is changed from dynamic seal adopted by input shaft input to static seal adopted by the shell precast oil duct, on one hand, system leakage can be avoided, system efficiency is improved, on the other hand, the area of a piston cavity can be reduced, a low-pressure hydraulic system can be technically expanded into a high-pressure hydraulic system, the oil filling volume of the piston cavity is reduced, the requirement of the hydraulic system on the maximum flow of a hydraulic pump is reduced, and the power energy consumption of the hydraulic pump is reduced.

The output gear 20 has a friction plate and steel plate set 63 mounted thereon. The output gear 20 has internal splines connected to the steel plates and is rigidly connected to external splines of the friction plates and the steel plate set 63. The internal spline may be formed by powder metallurgy or forging. Referring also to fig. 4, a clutch outer housing 30 may be welded to the output gear 20, the clutch outer housing 30 housing a friction plate and steel plate set 63. The output gear scheme integrating the internal spline is preferred, so that parts and processing cost can be saved, space arrangement can be more flexible and compact, and better structural strength can be achieved.

The clutch outer housing characteristic arrangement is preferably integrated into the output gear, and the internal spline matched with the steel sheet is processed by adopting a powder metallurgy or forging processing mode, so that the clutch outer housing is omitted, and as shown in fig. 3, the space and the cost are saved; or the stamping outer shell with the spline is welded with the output gear into a whole, as shown in fig. 2, so that the output gear is connected with the steel sheet.

Reference may be made to fig. 3 and 4. The output gear 20 can be further provided with a boss structure 632 for limiting the friction plate and the steel sheet group 63, the gear hub is provided with the boss structure for limiting axial movement, so that stress distribution of the pressed surfaces of the friction plate and the steel sheet group 63 is more uniform, load stiffness is better, supporting stiffness is improved without thick steel sheets, and compared with a traditional structure, the clamp ring limiting is canceled.

The actuator piston 64 is connected to the return spring 61, and the return spring 61 is fixed to the inner housing assembly 50. The return spring 63 is preferably disk-shaped.

Because the stationary piston 66 is mounted within the piston chamber 42 of the first housing 41 of the transmission housing 40, the hydraulic system clutch control valve may control the passage of oil into and out of the piston chamber 42 through the housing control gallery 44, thereby effecting translation of the stationary piston 66. One end of the release bearing 62 is attached to the end face of the fixed piston 66, the other end is matched with the actuating piston 64, the piston force is transmitted to the actuating piston 64, the friction plate and the steel plate set 63 are finally compressed, and the release bearing can rotate the actuating piston 64 and the fixed piston 66 with a rotating speed difference, so that the piston can keep not rotating under any working condition. The return spring 61 is attached to the end face of the 6# inner shell component and the 15# execution piston, when the piston is pushed by oil pressure, the release bearing 62 and the execution piston 64 are pushed to compress the return spring 61 component to move towards the output gear 20 side, so that the friction plate and the steel plate group 63 are compressed, the combination of the clutch is realized, and the power output of the engine can be transmitted to the wheel end. After the oil pressure of the piston cavity is relieved, the compressed return spring 61 disc reversely pushes the execution piston 64 to return, so that the fixed piston 66 is pushed back to the initial position, and the clutch is separated.

The return spring 61 and the friction plate and steel plate set 63 are housed in the clutch inner housing assembly 50. The clutch inner housing assembly 50 is connected, preferably splined, to the input shaft 10 of the transmission of the hybrid powertrain, and the clutch inner housing assembly 50 rotates the friction plate and steel plate set 63 with the input shaft 10. The return spring 61 is abutted against the end surfaces of the inner housing assembly 50 and the actuator piston 64. When the fixed piston 66 is pushed by oil pressure, the release bearing 62 and the actuating piston 64 are pushed to compress the return spring 61 assembly to move to the output gear 20 side, so that the friction plate and the steel plate group 63 are pressed, the combination of the clutch is realized, and the transmission of the engine power output to the wheel end can be realized. When the oil pressure in the piston cavity 42 is relieved, the compressed return spring 61 reversely pushes the execution piston 64 to return, so that the fixed piston 66 is pushed back to the initial position, and the clutch is separated.

The input shaft 12 is connected with the generator driving gear 14, the input shaft 12 and the generator driving gear 14 are fixed into a whole to form the input shaft assembly 10, and the input shaft 12 and the generator driving gear 14 are fixed into a whole, preferably welded, and the input shaft assembly 10 is supported on the second housing 43 and the first housing 41 by means of the first bearing 71 and the second bearing 73 respectively. A dynamic seal 124 is disposed between the second housing 43 and the input shaft 12. The input shaft assembly 10 is axially restrained by the clutch inner housing assembly 50, one end of the clutch inner housing assembly 50 being terminated to the output gear 20 and the other end abutting the inner race end face of the second bearing 73. The output gear 20 is sleeved on the input shaft 12 through a rolling bearing 75, the left side is limited in axial displacement through a baffle plate 80, and a lubricating oil groove 82 is formed in the baffle plate 80. One end of the input shaft 12 is connected with a damper 90, the damper 90 is connected with an engine crankshaft through a flywheel, and an input shaft oil seal 122 for sealing lubricating oil in the gearbox housing is arranged on a radial surface of the input shaft 12 matched with the first housing 41. That is, the engine crankshaft is coupled to a flywheel, which in turn is bolted to the end face of the damper 90. The damper 90 may be splined to the input shaft 12 to effect transmission of engine power to the transmission input shaft 12. The input shaft seal 122 seals the lubrication fluid within the transmission housing in cooperation with the smooth radial surface of the input shaft 12.

The release bearing 62 operatively separates the actuator piston 64, which rotates with the input shaft assembly 10, from the stationary piston 66, which is stationary mounted to the first housing 41, thereby providing for the absence of rotational centrifugal forces from the oil within the clutch piston chamber 42, eliminating the need for conventional balance chamber assemblies to balance the centrifugal oil pressure, and avoiding the need to control the amount of correction of the upper oil pressure as a function of rotational speed.

The piston cavity 42 arranged on the first shell 41 and used for accommodating the fixed piston 66 is of a static sealing structure, and the whole oil path from the hydraulic module to the piston cavity 42 is of static sealing.

The transmission mechanism for the hybrid power system is operated as follows:

when the TCU (Transmission Control Unit, end control unit) is not engaging the clutch control valve of the hydraulic system with the clutch command, the clutch 60 is in an open state, at which time the clutch piston chamber 42 is pressureless oil, and the actuator piston 64 is compressed by the spring preload and transfers the compression force to the piston through the release bearing 62, the pressureless force overcomes the piston lip friction and the spring preload, the stationary piston 66 is in a stationary state, no positive pressure is in a free state on the transmission for the hybrid system, and no torque is transferred. The inner housing assembly 50 rotates with the clutch plates with the input shaft, and the end caps and balls of the release bearing 62 against the end of the actuator piston 64 rotate with the actuator piston 64 with the inner housing assembly 50 due to the preload of the release spring, while the piston is stationary within the housing piston chamber. EV (Electric Vehicle) driving and series driving can be realized on a whole Vehicle control mode, the power of an engine is not transmitted to a wheel end through a clutch at the moment, the power of the engine is transmitted to a generator through a generator gear to be converted into Electric energy in a series working condition, the Electric energy can be directly output to a driving motor to drive wheels or redundant Electric energy is transmitted to a battery to be stored, and the parking power generation mode can only transmit the Electric energy to the battery to be stored so as to improve the SOC of the whole Vehicle;

when the TCU inputs a clutch combination signal to the clutch control valve of the hydraulic system, the hydraulic system fills the piston cavity 42 with oil through the housing control oil duct 44, after the piston cavity 42 reaches a force sufficient to overcome the pretightening force of the return spring 61, the fixed piston 66 starts to move leftwards, the release bearing 62 and the actuating piston 64 are pushed to move towards the compressing direction of the friction plate and the steel plate group 63, after the clearance between the steel plate and the friction plate is eliminated by the piston stroke, the piston cavity 42 keeps a certain oil pressure to compress the friction plate and the steel plate of the clutch, at this time, the clutch input end and the clutch output end, namely the inner housing assembly 50 and the output gear 20, have a certain rotation speed difference, and the clutch is in a sliding friction state. When the oil pressure is continuously increased, the speed difference at the two ends of the clutch can be reduced to 0rpm until the clutch is completely combined, at the moment, the wet clutch 60 can transmit the power of the engine to the wheel end, can work together with the driving motor to drive the wheels or output the redundant power to the generator to generate electricity so as to realize a series-parallel mode, or the engine can independently drive the vehicle so as to realize an engine direct driving mode.

In addition, when the engine is not required to participate in wheel end driving, the clutch 60 is opened, so that a series mode can be realized, or the engine can realize an EV mode without fuel injection. The clutch 60 is opened, the TCU provides a clutch control valve VBS valve (variable bleed solenoid; variable bleed solenoid valve) on the hydraulic module, namely, an actuating piston 64, outputs a clutch disengagement command, opens a valve core to unload the oil pressure in the piston cavity 42, a return spring 61 of the clutch releases the spring to compress the actuating piston 64 and a release bearing 62, the spring force is transmitted to a fixed piston 66, the fixed piston 66 extrudes the oil out of the piston cavity 42, so that the compressed friction plate and the steel plate set 63 are separated, the opening of the clutch is realized, and the disconnection from the engine power to the wheel end is realized.

The above-described transmission structure for power coupling of the hybrid system engine and the generator includes the damper 90, the input shaft 12, the clutch 60, the first and

second bearings

71 and 73, the output gear 20, the generator drive gear, the seal member 10, and the like. The clutch 60 may be comprised of key components such as a stationary piston 66, the output gear 20, the inner housing assembly 50, a friction and steel disc pack 63, an actuator piston 64, a return spring 61, a release bearing 62, and the like. The clutch 60 is preferably a wet clutch. When the clutch is combined, the power coupling of the engine and the generator can be transmitted to the wheel driving power flow, and the hybrid mode or the engine direct drive mode of the hybrid power system is realized. On the other hand, after the clutch is separated, the engine can increase the speed gear ratio, change the rotation speed ratio of the gear, input power into the generator to generate electricity, realize the whole car series mode or parking power generation mode, or realize that the vehicle is driven by the driving motor alone to realize the pure electric mode.

The invention also provides an automobile provided with any transmission mechanism for the hybrid power system.

In summary, the invention optimizes the rotation dynamic seal of the existing control oil duct to the static seal of the invention, solves the problem of high oil pressure leakage of the hydraulic system caused by the existence of the dynamic seal ring when the clutch is combined, improves the efficiency of the whole system, and reduces the carbon emission of the system; the piston cavity volume can be reduced in the scheme, the hydraulic system can be expanded to a high-pressure system, the requirement on the rated flow of the hydraulic pump can be reduced, the power requirement is reduced, the system is more efficient, and the system cost is reduced. The control oil duct of the clutch piston cavity is drilled from the shaft to be a precast oil duct from the gearbox shell, so that the manufacturing process difficulty of the long and thin holes on the shaft which are difficult to process and clean is solved, the processing cost is reduced, the cleanliness of the oil duct is guaranteed, and the clutch control valve is prevented from being blocked and blocked by impurities. In addition, the clutch piston is static and does not rotate, and the centrifugal pressure is not generated by the oil in the piston cavity, so that nonlinear deviation increase of the relation between the oil pressure and the torque characteristic of the clutch is not caused, the self-learning interpolation is facilitated to be controlled, and a balance cavity is not needed to be arranged on the clutch structure to offset the centrifugal pressure of the piston cavity, so that one part structure is saved, and the structure is more compact and the cost is reduced. According to the invention, the clutch outer shell and the output gear are welded into a whole to compress the axial dimension, and the spline which is matched and connected with the clutch steel sheet is processed by forging or powder metallurgy of the output gear, so that the output gear and the gear are highly integrated into one part, the part and processing cost can be saved, the space arrangement can be more flexible and compact, and the invention is favorable for the platform expansion of a high-pressure hydraulic system. And can possess better structural strength.

The terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like herein refer to an azimuth or positional relationship based on that shown in the drawings, or that is commonly put in place when the inventive product is used, merely to facilitate description of the invention and simplify description, and do not indicate or imply that the apparatus or elements referred to must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the invention. The terms "first," "second," "third," and the like are used merely to distinguish between descriptions and are not to be construed as indicating or implying relative importance. The terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; may be mechanically connected, may be electrically connected or may communicate with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A transmission for a hybrid powertrain comprising an output gear (20), an input shaft (12) and a gearbox housing (40), characterized in that: a clutch (60) is arranged between the output gear (20) and the input shaft (12), the clutch (60) comprises an execution piston (64) and a fixed piston (66) which are connected through a release bearing (62), the fixed piston (66) is arranged in a piston cavity (42), the piston cavity (42) is arranged on a gearbox housing (40), and a housing control oil duct (44) communicated with the piston cavity (42) is arranged on the gearbox housing (40).

2. The transmission for a hybrid powertrain of claim 1, wherein: the device further comprises an inner shell assembly (50) and a return spring (61), wherein the actuating piston (64) is connected to the return spring (61), and the return spring (61) is fixed to the inner shell assembly (50).

3. The transmission for a hybrid system according to claim 2, characterized in that: the friction plate and steel sheet group (63) are arranged on the output gear (20), and the output gear (20) is provided with an internal spline which is in rigid connection with the external spline of the friction plate and steel sheet group (63).

4. A transmission for a hybrid powertrain as set forth in claim 3, wherein: the clutch outer housing (30) is fixedly connected to the output gear (20), and the clutch outer housing (30) accommodates the friction plate and the steel sheet set (63).

5. The transmission for a hybrid powertrain of claim 1, wherein: the return spring (61) and the friction plate and steel sheet set (63) are accommodated in the clutch inner housing assembly (50), the clutch inner housing assembly (50) is connected to an input shaft (12) of a transmission mechanism of the hybrid power system, and the clutch inner housing assembly (50) drives the friction plate and steel sheet set (63) to rotate along with the input shaft (12).

6. The transmission for a hybrid powertrain of claim 5, wherein: the input shaft (12) is connected with a generator driving gear, the input shaft (12) and the generator driving gear are fixed into a whole to form an input shaft assembly (10), and the input shaft assembly (10) is respectively supported on a second shell (43) and a first shell (41) by means of a first bearing (71) and a second bearing (73).

7. The transmission for a hybrid powertrain of claim 6, wherein:

the input shaft assembly (10) is axially limited through the clutch inner housing assembly (50), one end of the clutch inner housing assembly (50) is clamped on the output gear (20), and the other end of the clutch inner housing assembly is abutted against the end face of the inner ring of the second bearing (73);

the output gear (20) is sleeved on the input shaft (12) in an empty mode through a rolling bearing (75), and the left side of the output gear is limited in axial displacement through a baffle plate (80).

8. The transmission for a hybrid powertrain of claim 6, wherein: the right end of the input shaft (12) is connected with a shock absorber (90), the shock absorber (90) is connected with an engine crankshaft through a flywheel, and an input shaft (12) oil seal for sealing lubricating oil in a gearbox housing (40) is arranged on a radial surface of the input shaft (12) matched with the first housing (41).

9. A transmission for a hybrid powertrain as set forth in claim 3, wherein: the output gear (20) is provided with a boss structure (632) for limiting the friction plate and steel plate group (63).

10. An automobile, characterized in that the automobile has a transmission mechanism for a hybrid system according to any one of claims 1 to 9.