CN113983083B

CN113983083B - Weak circulation pump air cooling clutch cavity structure

Info

Publication number: CN113983083B
Application number: CN202111162641.3A
Authority: CN
Inventors: 邹利亚; 陈永斌; 周泉钢
Original assignee: Dongfeng Commercial Vehicle Co Ltd
Current assignee: Dongfeng Commercial Vehicle Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-05-12
Anticipated expiration: 2041-09-30
Also published as: CN113983083A

Abstract

The invention discloses a weak circulation pumping air-cooled clutch cavity structure, which comprises a flywheel shell and a gearbox front shell, wherein the flywheel shell is fixed in the front and back directions, and a clutch shell structure which is coaxial with the flywheel disc, can axially rotate and axially move forwards and backwards is arranged in the gearbox front shell; the flywheel disc is eccentrically fixed in the flywheel shell, and the gap between the bottom surface of the flywheel disc and the inner surface of the bottom of the flywheel shell is smaller than the gap between the top surface of the flywheel disc and the inner surface of the top of the flywheel shell; the clutch housing structure is provided with a shank structure for disturbing air. According to the invention, the ventilation capacity of the clutch cavity is greatly improved through the shank clutch and the clutch eccentric pump air cavity structure, and the cooling and dust removing effects are improved.

Description

Weak circulation pump air cooling clutch cavity structure

Technical Field

The invention relates to the technical field of automobile power assembly equipment, in particular to a cavity structure of a weak circulation pumping air cooling clutch.

Background

The clutch of the vehicle power assembly works in a clutch cavity (formed by a flywheel shell and a front gearbox shell), the clutch has the functions of connection and disconnection in the driving process, and the rotation speed difference exists between the flywheel and a clutch pressure plate and a driven plate in the connection process, so that friction heat generation is caused. In the frequent engagement and disengagement process of the clutch, the temperature (hereinafter referred to as cavity temperature) in the clutch cavity rises sharply due to friction heat, and experiments show that the cavity temperature can reach 170 ℃ or higher at the highest in the sealed clutch cavity, so that the lubricating grease of the clutch release bearing fails, the clutch loses working function, and the vehicle is stopped. Meanwhile, in the clutch engagement process, dust is generated by friction between the flywheel and the pressure plate, and a large amount of dust can bring reliability risks to the clutch and the clutch release bearing in the vehicle operation life cycle.

Patent application number 201310295612.3, patent name of "automobile fan rotational flow cover assembly cooled by forced fan clutch" discloses an automobile fan rotational flow cover assembly cooled by forced fan clutch, one end of which is square air inlet, and the other end is circular air outlet. The cyclone cover is internally provided with 1-5 different diverter rings, the diverter rings are of conical ring structures with air inlets larger than air outlets in diameter, the specific diameter ratio is determined according to the sizes of fans and fan clutches and the cooling requirements of the fan clutches, the diverter rings are applied to commercial vehicles, the ratio of the diverter rings to the commercial vehicles is smaller than that of the commercial vehicles, the extremely special vehicles can be adjusted, and the diverter rings are used for dividing air entering the assembly. The innermost shunt ring is referred to by reference numerals, so that the air entering the inside of the shunt ring can forcedly flow through the surface of the fan clutch, the fan clutch is forcedly cooled by the air, and the diameter ratio of the air inlet and the air outlet of the inner shunt ring directly influences the cooling effect of the fan clutch, so that the diameter ratio is determined according to the cooling requirement of the fan clutch. The flow dividing ring and the swirl cover body are connected with 3-30 spoilers (the specific number is determined according to the distribution of the flow direction of the air of the assembly), the surface shape of each spoiler is a changed curved surface, the curvature of the curved surface is changed according to the shape of the matched fan blade, the flow dividing ring and the swirl cover body are used for forming a plurality of independent air circulation units, and the air flows out of each unit in a rotating way of the fan blade, so that the purpose of reducing the turbulence by stably flowing the air is realized. In addition, sealing strips are stuck on the upper edge and the lower edge of the outer surface of the air inlet of the assembly; the left and right sides of the air inlet of the assembly are respectively provided with 2-5 positioning holes and mounting long holes. In addition, in order to adapt to the cooling system requirement, the air inlet center and the air outlet center of the assembly and the air inlet center and the air outlet center of the flow divider can be designed into a structure with the eccentricity of H value according to actual conditions.

The patent with the application number of 201921710949.5 discloses a cleaning temperature control clutch with an airflow cleaning spoiler, which comprises a temperature sensor, a front cover, a valve rod, a sealing ring, a valve plate and a separation disc, wherein the valve rod penetrates through the front cover and extends to the rear side of the front cover; the front end of the front cover is provided with a circular groove in clearance fit with the temperature sensor, the inner wall of the circular groove at the front side of the temperature sensor is provided with a cleaning mechanism, the cleaning mechanism comprises a plurality of airflow cleaning spoilers fixed on the inner wall of the circular groove, the airflow cleaning spoilers extend from the inner wall of the circular groove to the middle, and the cross section of the airflow cleaning spoilers is arc-shaped. The air flow with pressure can be generated when the front cover rotates to generate a cleaning effect on the temperature sensor. The rear end of the valve rod is riveted with a valve plate, the rear side of the valve plate is provided with a separation disc, an oil storage cavity is formed between the separation disc and the front cover, and the separation disc is provided with an oil outlet; the valve rod is provided with two annular sealing grooves, and sealing rings are embedded in the annular sealing grooves and are positioned between the valve rod and the front cover. Can realize the sealing between valve rod and the protecgulum, the preferred sealing washer is the rotation sealing washer. A good seal can be ensured when the valve stem is rotated relative to the front cover. The temperature sensor is wholly spiral. And silica gel is filled between the temperature sensor and the external inserting groove for fixation. The rear end of valve rod is equipped with square boss, is equipped with on the valve block with square boss complex hole. The cooperation of square boss and hole can carry out spacing and axial positioning to the valve block. Further, for axial positioning, the cross-sectional area of the square boss is smaller than the area of the hole in the valve plate. The inner end of the air flow cleaning spoiler is inclined towards one side of the front cover, which is in the same direction with the rotating direction. The rotation direction of the air flow cleaning spoiler is designed to be consistent with the forward rotation and the reverse rotation of the temperature control clutch according to the forward rotation and the reverse rotation requirements of the temperature control clutch, so that the temperature control clutches with different rotation directions are satisfied. The oil outlet holes are symmetrically arranged on the separation disc, the valve plates are of symmetrical structures, and the two oil outlet holes are respectively plugged. The bottom of the air flow cleaning spoiler is fixedly provided with bristles. The bristles can be cleaned by friction. The oil outlet holes on the separation disc are arranged in a plurality and distributed in a ring-shaped array within the range of 10-15 degrees. The temperature sensor senses that different heating deformation amounts gradually increase, so that the rotating angle of the valve plate gradually increases, the number of the opened oil outlet holes is gradually increased along with the gradual increase of the rotating angle of the valve plate, so that the higher temperature can be reached to open more oil outlet holes, the circulation flux of silicone oil is increased, the action of the transmission force is correspondingly improved, and finally the rotating speed of the front cover is increased along with the temperature increase until the oil outlet holes are all opened.

The scheme of cooling and dedusting of the existing clutch assembly is that a window is opened on a front shell of a gearbox for opening holes, and cavity temperature cooling and dedusting are carried out through natural ventilation. The existing clutch cavity natural ventilation cooling and dust removal scheme has the following defects: the ability to naturally cool only through the clutch cavity vents is low; the dust removal capability of the clutch cavity under the natural ventilation condition is very low.

Disclosure of Invention

The invention aims to solve the defects of the background technology and provides a weak circulation pumping air cooling clutch cavity structure capable of realizing cooling and dust removal in a clutch cavity.

The invention provides a weak circulation pumping air-cooled clutch cavity structure, which comprises a flywheel shell and a gearbox front shell, wherein the flywheel shell is fixed in the front shell, and the gearbox front shell is internally provided with a clutch shell structure which is coaxial with the flywheel disc, can axially rotate and axially move forwards and backwards; the method is characterized in that: the flywheel disc is eccentrically fixed in the flywheel shell, and the gap between the bottom surface of the flywheel disc and the inner surface of the bottom of the flywheel shell is smaller than the gap between the top surface of the flywheel disc and the inner surface of the top of the flywheel shell; the clutch housing structure is provided with a shank structure for disturbing air.

Further, an air inlet channel communicated with the inner cavity of the flywheel housing is formed in the front end face of the flywheel housing along the axial direction of the flywheel housing, and the front end of the flywheel disc is coaxially fixed to the rear end of the air inlet channel.

Further, an eccentric hole which is eccentrically upwards communicated with the inner cavity of the flywheel housing is formed in the rear end face of the flywheel housing.

Further, a ventilation curved channel communicated with the inner cavity of the flywheel housing is formed in the rear end face of the flywheel housing, and a front housing ventilation channel communicated with the ventilation curved channel is formed in the front end face of the front housing of the gearbox.

Further, the ventilation curved path comprises an upper ventilation curved path positioned at the top of the rear end face of the flywheel housing and lower ventilation curved paths positioned at the left and right sides of the lower part of the rear end face of the flywheel housing, and the front shell ventilation path comprises a front shell upper ventilation path positioned at the top of the front end face of the front shell of the gearbox and a front shell lower ventilation path positioned at the left and right sides of the lower part of the front shell of the gearbox.

Further, the upper ventilation curved channel comprises a longitudinal channel with an air inlet arranged on the top surface of the rear end of the flywheel housing and extending downwards, and a transverse channel which is communicated with the bottom of the longitudinal channel, is vertical to the longitudinal channel and is communicated with the inner cavity of the flywheel housing.

Further, the lower ventilation curved channel comprises a first vertical channel, a connecting channel and a second vertical channel, wherein the air inlet is formed in the bottom surface of the rear end of the flywheel housing and extends upwards, the connecting channel is communicated with the top end of the first vertical channel at an angle and extends towards the outer side of the flywheel housing, the second vertical channel is communicated with the outer end of the connecting channel and extends towards the inner cavity of the flywheel housing, and the second vertical channel is communicated with the inner cavity of the flywheel housing.

Further, the clutch housing structure comprises a clutch housing and a pressure plate coaxially fixed in the clutch housing and axially attached to the flywheel disc, and the shank structure comprises a first shank structure arranged on the surface of the clutch housing and a second shank structure arranged in the clutch housing.

Further, the first shank structure includes elongated pumping shanks fixed at intervals along a circumferential side surface of the clutch housing.

Further, the second shank structure includes end face shank plates fixed at intervals along the circumferential inner side end face of the clutch housing, which includes a first fixed end plate fixed to the center side of the inner surface of the clutch housing, a second fixed end plate fixed to the outer side of the inner surface of the clutch housing, and a tapered shank plate fixedly connected between the first fixed end plate and the second fixed end plate and integrally formed with the first fixed end plate and the second fixed end plate; the first fixed end piece with the second fixed end piece all be with the rectangle end piece of clutch housing internal surface laminating, the width of second fixed end piece is greater than the width of first fixed end piece, the toper shin piece with the width of second fixed end piece fixed connection's one end is greater than the toper shin piece with the width of first fixed end piece fixed connection's one end.

The beneficial effects of the invention are as follows: the reliability failure fault of the release bearing caused by high temperature, dust and the like of the clutch cavity is reduced through the tibial plate design of the clutch. The design of the flywheel housing and the eccentric cavity of the front housing of the gearbox is utilized, and the design of the air inlet and outlet holes of the pump form an air circulation structure, so that the air disturbance in the clutch cavity is increased, the temperature in the cavity is reduced, and meanwhile, the dust accumulation is reduced.

Drawings

FIG. 1 is an axial cross-sectional view of a weak circulation pumping air-cooled clutch cavity structure in the present invention;

FIG. 2 is a rear view of the flywheel housing of the present invention;

FIG. 3 is an axial cross-sectional view of a clutch housing structure in accordance with the present invention;

FIG. 4 is a schematic structural view of a clutch housing according to the present invention;

fig. 5 is a front view of an end tibial patch of the present invention;

fig. 6 is a left side view of an end tibial patch of the present invention;

wherein, 1-flywheel shell, 2-gearbox front housing, 3-flywheel dish, 4-clutch housing structure (4.1-clutch housing, 4.2-pressure disk), 5-air inlet passageway, 6-eccentric hole, 7-upper ventilation curved way (7.1-longitudinal channel, 7.2-transverse channel), 8-lower ventilation curved way (8.1-first vertical channel, 8.2-second vertical channel, 8.3-connecting channel), 9-front housing upper ventilation channel, 10-front housing lower ventilation channel, 11-pumping shin piece, 12-terminal shin piece (12.1-first fixed end piece, 12.2-second fixed end piece, 12.3-toper shin piece).

Detailed Description

The invention will now be described in further detail with reference to the drawings and to specific examples. The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments.

In the description of the present invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present invention and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

The weak circulation pumping air-cooled clutch cavity structure shown in fig. 1-6 comprises a flywheel shell 1 and a gearbox front shell 2 which are fixed in front and back, wherein an air inlet channel 5 communicated with the inner cavity of the flywheel shell 1 is axially formed in the front end face of the flywheel shell 1, the front end of a flywheel disc 3 is coaxially fixed at the rear end of the air inlet channel 5, and an eccentric hole 6 which is eccentrically upwards communicated with the inner cavity of the flywheel shell 1 is formed in the rear end face of the flywheel shell 1. The flywheel disc 3 is eccentrically fixed in the flywheel shell 1, and the gap between the bottom surface of the flywheel disc 3 and the inner surface of the bottom of the flywheel shell 1 is smaller than the gap between the top surface of the flywheel disc 3 and the inner surface of the top of the flywheel shell 1. The rear end face of the flywheel housing 1 is provided with a ventilation curved passage communicated with the internal cavity of the flywheel housing 1, and the front end face of the gearbox front housing 2 is provided with a front housing ventilation passage communicated with the ventilation curved passage. The ventilation curved path comprises an upper ventilation curved path 7 positioned at the top of the rear end face of the flywheel housing 1 and lower ventilation curved paths 8 positioned at the left and right sides of the lower part of the rear end face of the flywheel housing 1, and the front housing ventilation path comprises a front housing upper ventilation path 9 positioned at the top of the front end face of the front housing 2 of the gearbox and a front housing lower ventilation path 10 positioned at the left and right sides of the lower part of the front housing 2 of the gearbox. The upper ventilation curve 7 comprises a longitudinal channel 7.1 with an air inlet arranged on the top surface of the rear end of the flywheel housing 1 and extending downwards, and a transverse channel 7.2 which is communicated with the bottom of the longitudinal channel 7.1, is vertical to the longitudinal channel 7.1 and is communicated with the inner cavity of the flywheel housing 1. The lower ventilation curved passage 8 comprises a first vertical passage 8.1, a connecting passage 8.3 and a second vertical passage 8.2, wherein the air inlet is formed in the bottom surface of the rear end of the flywheel housing 1 and extends upwards, the connecting passage 8.3 is communicated with the top end of the first vertical passage 8.1 at an angle and extends towards the outer side of the flywheel housing 1, the second vertical passage 8.2 is communicated with the outer end of the connecting passage 8.3 and extends towards the inner cavity of the flywheel housing 1, and the second vertical passage is communicated with the inner cavity of the flywheel housing 1.

A clutch housing structure 4 which is coaxial with the flywheel disc 3, can axially rotate and axially move back and forth is arranged in the gearbox front housing 2, and a shank structure for disturbing air is arranged on the clutch housing structure 4. The clutch housing structure 4 comprises a clutch housing 4.1 and a pressure plate 4.2 coaxially fixed in the clutch housing 4.1 and axially attached to the flywheel disc 3, and the shank structure comprises a first shank structure arranged on the surface of the clutch housing 4.1 and a second shank structure arranged in the clutch housing 4.1. The first shank structure comprises elongated pumping shanks 11 spaced along the circumferential side surface of the clutch housing 4.1. The second shank structure includes end face shank pieces 12 fixed at intervals along the circumferential inner end face of the clutch housing 4.1, which includes a first fixed end piece 12.1 fixed to the center side of the inner surface of the clutch housing 4.1, a second fixed end piece 12.2 fixed to the outer side of the inner surface of the clutch housing 4.1, and a tapered shank piece 12.3 fixedly connected between the first fixed end piece 12.1 and the second fixed end piece 12.2 and integrally structured with the first fixed end piece 12.1 and the second fixed end piece 12.2; the first fixing end piece 12.1 and the second fixing end piece 12.2 are rectangular end pieces attached to the inner surface of the clutch housing 4.1, the width of the second fixing end piece 12.2 is larger than that of the first fixing end piece 12.1, and the width of one end fixedly connected with the conical shank piece 12.3 and the second fixing end piece 12.2 is larger than that of one end fixedly connected with the first fixing end piece 12.1.

According to the invention, the shank pieces with the length of 10 mm/width of 6 mm/thickness of 3mm are manufactured on the 4.1 circumference of the clutch housing or the front surface of the clutch housing, 36 pieces or 48 pieces are uniformly distributed, and the conical shank pieces 12.3 of the end face shank pieces 12 are axial shrinkage shank pieces with the angle of 4 degrees. The flywheel housing 1 and the front gearbox housing 2 are eccentrically designed in the upper center, so that when the clutch housing structure 4 and the flywheel disc 3 assembly rotate in operation, a pumping cavity is formed in the upper and lower areas of the cavity, two ventilation curved passages are symmetrically designed below the cavity, the pressure is gradually increased due to the gradual decrease of the cavity volume in the clockwise rotation direction of the clutch housing 4, the cavity volume is gradually increased after passing through the lowest position, the pressure is gradually decreased, and the left air inlet channel 5 is formed in the cavity to suck air, and the right air outlet circulating flow is formed. The ventilation holes need to be designed into a tortuous path (ventilation curved path) to prevent foreign matters such as external silt from entering the cavity. It is predicted that due to the ventilation air flow in the clutch cavity, it is easier to disturb the discharge of the radial dust deposited under the cavity during ventilation.

In the invention, the reliability failure fault of the release bearing caused by high temperature, dust and the like in the clutch cavity is reduced by the tibial design of the inside and the outside of the clutch housing 4. By utilizing the eccentric cavity designs of the flywheel housing 1 and the gearbox front housing 2 and the pumping air inlet and outlet hole designs, a pumping circulation structure is formed, the air disturbance in the clutch cavity is increased, the temperature in the cavity is reduced, and meanwhile, the dust accumulation is reduced.

Here, it should be noted that the description of the above technical solution is exemplary, and the present specification may be embodied in different forms and should not be construed as being limited to the technical solution set forth herein. Rather, these descriptions will be provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Furthermore, the technical solution of the invention is limited only by the scope of the claims.

It should be understood that the specific order or hierarchy of steps in the processes disclosed are examples of exemplary approaches. Based on design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The shapes, dimensions, ratios, angles, and numbers disclosed for describing aspects of the present specification and claims are merely examples, and thus, the present specification and claims are not limited to the details shown. In the following description, a detailed description of related known functions or configurations will be omitted when it may be determined that the emphasis of the present specification and claims is unnecessarily obscured.

The foregoing description of the embodiments and specific examples of the present invention has been presented for purposes of illustration and description; this is not the only form of practicing or implementing the invention as embodied. The description covers the features of the embodiments and the method steps and sequences for constructing and operating the embodiments. However, other embodiments may be utilized to achieve the same or equivalent functions and sequences of steps.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate preferred embodiment of this invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. As will be apparent to those skilled in the art; various modifications to these embodiments will be readily apparent, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the invention is not limited to the above-described embodiments, but many variations are possible. Any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention should be considered to be within the scope of the present invention.

Claims

1. The utility model provides a weak circulation pump air-cooled clutch cavity structure, includes flywheel housing (1) and gearbox front housing (2) that front and back are fixed, flywheel housing (1) internal fixation has flywheel dish (3), be provided with in gearbox front housing (2) with flywheel dish (3) coaxial, clutch housing structure (4) that can axial rotation and axial back and forth movement; the method is characterized in that: the flywheel disc (3) is eccentrically fixed in the flywheel shell (1), and a gap between the bottom surface of the flywheel disc (3) and the inner surface of the bottom of the flywheel shell (1) is smaller than a gap between the top surface of the flywheel disc (3) and the inner surface of the top of the flywheel shell (1); the clutch housing structure (4) is provided with a shank structure for disturbing air; an air inlet channel (5) communicated with the inner cavity of the flywheel shell (1) is formed in the front end face of the flywheel shell (1) along the axial direction of the flywheel shell, and the front end of the flywheel disc (3) is coaxially fixed at the rear end of the air inlet channel (5); an eccentric hole (6) which is eccentrically upwards communicated with the inner cavity of the flywheel housing (1) is formed in the rear end face of the flywheel housing (1); the clutch housing structure (4) comprises a clutch housing (4.1) and a pressure plate (4.2) coaxially fixed in the clutch housing (4.1) and capable of being axially attached to the flywheel disc (3), and the shank structure comprises a first shank structure arranged on the surface of the clutch housing (4.1) and a second shank structure arranged in the clutch housing (4.1); the first shank structure comprises elongated pumping shank (11) fixed at intervals along the circumferential side surface of the clutch housing (4.1); the second shank structure comprises end shank pieces (12) fixed at intervals along the circumferential inner end face of the clutch housing (4.1), and comprises a first fixed end piece (12.1) fixed on the center side of the inner surface of the clutch housing (4.1), a second fixed end piece (12.2) fixed on the outer side of the inner surface of the clutch housing (4.1) and a conical shank piece (12.3) fixedly connected between the first fixed end piece (12.1) and the second fixed end piece (12.2) and integrally structured with the first fixed end piece (12.1) and the second fixed end piece (12.2); the first fixed end piece (12.1) and the second fixed end piece (12.2) are rectangular end pieces attached to the inner surface of the clutch housing (4.1), the width of the second fixed end piece (12.2) is larger than that of the first fixed end piece (12.1), and the width of one end fixedly connected with the second fixed end piece (12.2) is larger than that of one end fixedly connected with the first fixed end piece (12.1) and the second fixed end piece (12.3).

2. The weak circulation pumping air-cooled clutch cavity structure of claim 1, wherein: the novel flywheel comprises a flywheel shell, and is characterized in that a ventilation curved passage communicated with an inner cavity of the flywheel shell (1) is formed in the rear end face of the flywheel shell (1), and a front shell air passage communicated with the ventilation curved passage is formed in the front end face of a front gearbox shell (2).

3. The weak circulation pumping air-cooled clutch cavity structure of claim 2, wherein: the ventilation curved ways comprise an upper ventilation curved way (7) positioned at the top of the rear end face of the flywheel housing (1) and lower ventilation curved ways (8) positioned at the left and right sides of the lower part of the rear end face of the flywheel housing (1), and the front housing ventilation ways comprise a front housing upper ventilation way (9) positioned at the top of the front end face of the front housing (2) of the gearbox and a front housing lower ventilation way (10) positioned at the left and right sides of the lower part of the front housing (2) of the gearbox.

4. A weak circulation pumping air cooled clutch cavity structure as defined in claim 3, wherein: the upper ventilation curved passage (7) comprises a longitudinal passage (7.1) with an air inlet arranged on the top surface of the rear end of the flywheel housing (1) and extending downwards, and a transverse passage (7.2) which is communicated with the bottom of the longitudinal passage (7.1), is perpendicular to the longitudinal passage (7.1) and is communicated with the inner cavity of the flywheel housing (1).

5. A weak circulation pumping air cooled clutch cavity structure as defined in claim 3, wherein: the lower ventilation curved passage (8) comprises a first vertical passage (8.1) which is formed by an air inlet at the bottom surface of the rear end of the flywheel housing (1) and extends upwards, a connecting passage (8.3) which is communicated with the top end of the first vertical passage (8.1) at an angle and extends towards the outer side of the flywheel housing (1), and a second vertical passage (8.2) which is communicated with the outer end of the connecting passage (8.3) and extends towards the inner cavity of the flywheel housing (1) and is communicated with the inner cavity of the flywheel housing (1).