CN111775629B

CN111775629B - Driving axle

Info

Publication number: CN111775629B
Application number: CN202010663620.9A
Authority: CN
Inventors: 董红彭; 金刚强
Original assignee: Zhejiang Jindao Technology Co ltd
Current assignee: Zhejiang Jindao Technology Co ltd
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2024-01-30
Anticipated expiration: 2040-07-10
Also published as: CN111775629A

Abstract

The invention discloses a drive axle, which comprises an axle housing, an input assembly, two service brake assemblies, two half shafts and two hub assemblies, wherein the two half shafts and the two hub assemblies are coaxially distributed, the axle housing comprises a first housing and two second housings which are fixedly connected, the two second housings are respectively positioned at the left side and the right side of the first housing, the service brake assemblies are positioned in the second housings and sleeved on the half shafts, the hub assemblies are arranged at the outer ends of the second housings and are fixedly connected with the outer ends of the half shafts, the input assembly is arranged on the first housing, and the input assembly comprises an input shaft and an output shaft which are transversely arranged, so that the drive axle housing is reasonable in structure and small in size, and the occupied space of the drive axle is reduced.

Description

Driving axle

Technical Field

The invention relates to the technical field of automobiles, in particular to a drive axle.

Background

As is well known, the use condition of engineering machinery is relatively bad, at present, the domestic engineering machinery axle product market is still mainly based on a dry brake driving axle, and meanwhile, the dry driving axle adopts external dry brake, so that the dry driving axle is greatly influenced by environmental factors such as humidity, freezing, dust and the like, the braking performance is unstable, and the service life is short; the wet brake is built-in, is basically not influenced by environmental factors, has long service life and safe and reliable brake, and has wide application in the existing engineering machinery.

In the prior art, the application of the drive axle to the forklift is a precedent, for example, a chinese patent document with publication number CN107265354a discloses a forklift driving parking integrated drive axle, which comprises an input assembly, an axle housing, a first half axle, a second half axle, a spline housing, a fixed gear ring, and a first brake assembly and a second brake assembly positioned in the axle housing.

In addition, the power of the existing drive axle is often provided by a speed changer, so that the vibration transmitted by a hub on the drive axle is easily transmitted to the speed changer, when the speed changer body is subjected to the vibration, the vibration of an automobile is caused, the noise with different degrees is generated, and meanwhile, the vibration of the speed changer body also easily causes the damage of internal parts of the speed changer;

Thus, chinese patent publication No. CN110043585a discloses a transaxle, which includes an axle housing, an input assembly, a first brake assembly, a first half axle, a first hub component, a second half axle, a second brake assembly and a second hub component, the second brake assembly is identical in structure to the brake assembly, the input assembly is mounted on the axle housing, the first brake assembly is located at the left end of the axle housing, the right section of the first half axle is connected to the input assembly, the first half axle passes through the first brake assembly, the second brake assembly is located at the right end of the axle housing, the left section of the second half axle is connected to the input assembly, and the second half axle passes through the second brake assembly; the first braking assembly and the second braking assembly can compensate the abrasion of the friction plate so as to prolong the service life of the friction plate, and the input assembly can be provided with a buffer mechanism, so that the influence of the vibration of the drive axle on the transmission can be effectively reduced, and the service life of the drive axle is prolonged.

However, those skilled in the art will find that the above-described drive axle has the following disadvantages during use:

1) The input shaft and the output shaft in the input assembly are vertically arranged; the driving axle occupies a large space;

2) The friction plate in the service brake assembly is directly arranged on the half shaft, so that the arrangement is convenient for the installation of the friction plate, but makes the installation of the half shaft difficult, and makes the opening of the shell larger, so that the hub component has a complex structure and the transmission relation with the half shaft is complex;

3) The transmission level between the parking handle and the braking friction plate in the parking braking assembly is at least 2 levels, and the torque is small.

Disclosure of Invention

The first object of the present invention is to provide a driving axle, which aims at the problem of large occupied space of the driving axle, and comprises an input assembly, wherein the input assembly comprises an input shaft and an output shaft which are transversely arranged, so that the driving axle housing has reasonable structure and reduced volume, and the occupied space of the driving axle is reduced.

In order to achieve the first object, the present invention adopts the following technical scheme:

the driving axle comprises an axle housing, an input assembly, two service brake assemblies, two half shafts and two hub components, wherein the half shafts and the two hub components are coaxially distributed, the axle housing comprises a first housing and two second housings which are fixedly connected, the two second housings are respectively positioned at the left side and the right side of the first housing, the service brake assemblies are positioned in the second housings and sleeved on the half shafts, the hub components are arranged at the outer ends of the second housings and are fixedly connected with the outer ends of the half shafts, and the input assembly is arranged on the first housing;

The input assembly comprises a differential assembly, the differential assembly comprises a differential shell, a first planetary gear and two side gears, the differential shell is arranged on the inside of the first shell and can rotate in the first shell, the first planetary gear is arranged in the inside of the differential shell and can rotate along with the differential shell, the two side gears are respectively positioned on the left side and the right side of the inside of the differential shell, the two side gears are engaged with the first planetary gear, and the inner end of each side shaft extends into the differential shell and is in transmission connection with the side gear;

it is characterized in that the method comprises the steps of,

the input assembly further comprises an input shaft, an intermediate shaft, a first gear and a second gear which are arranged on the first shell, the input shaft is in transmission connection with the motor, the first gear is sleeved on the intermediate shaft and in transmission connection with the intermediate shaft, the first gear is in transmission fit with the input shaft, the second gear is in transmission fit with the intermediate shaft, the second gear is fixedly connected with the differential shell, and the input shaft, the intermediate shaft and the two half shafts are transversely distributed;

the driving brake assembly comprises a first shaft sleeve, an annular piston, a plurality of annular first outer friction plates and a plurality of annular first inner friction plates, wherein the first shaft sleeve is in transmission fit with a half shaft through an internal spline, the first outer friction plates are in axial clearance fit with the circumferential positioning of the first shell, the first inner friction plates are in axial clearance fit with the circumferential positioning of the first shaft sleeve, the plurality of annular first inner friction plates and the first outer friction plates are alternately overlapped with each other, and the piston is arranged on the second shell and can move between a braking position and a non-braking position;

The hub assembly comprises a second hub and a hub piece, the second hub is sleeved on the half shaft and fixedly connected with the outer end of the second shell, and the hub piece is fixedly connected with the half shaft;

when the service brake assembly is in a braking state, the piston moves to a braking position so that the first inner friction plates and the first outer friction plates are abutted against and pressed on the second sleeve.

Preferably, two first tapered roller bearings are further provided, the tapered roller bearings are sleeved on the second shaft sleeve, and the outer surfaces of the tapered roller bearings are abutted against the inner surface of the hub member.

Preferably, a first oil seal and a second oil seal are further provided, the first oil seal is located between the second axle sleeve and the hub piece, and the second oil seal is located between the half axle and the second axle sleeve.

Preferably, the elastic retainer ring is further arranged, an axial spline groove and a circumferential annular groove are formed in the outer surface of the first shaft sleeve, a plurality of first mounting grooves are formed in the inner side wall of the second shell, and the first outer friction plate is clamped in the first mounting grooves; the first inner friction plates are clamped in the spline grooves and are in transmission connection with the first shaft sleeve, and the circlip is clamped in the annular groove and positioned between any two adjacent first inner friction plates.

Preferably, a plurality of first bolts which are uniformly distributed circumferentially and a plurality of first springs which are sleeved on the first bolts are further arranged, a plurality of first through holes which are uniformly distributed circumferentially are formed in the first outer friction plates, one end of each first bolt penetrates through the first through holes in the plurality of first outer friction plates and abuts against the second shell, the other end of each first bolt abuts against the second shaft sleeve, the plurality of first springs are sequentially distributed between two adjacent first outer friction plates, two ends of each first spring abut against the two adjacent first outer friction plates respectively, and therefore the two adjacent first outer friction plates are separated by a certain distance through the first springs.

Preferably, the service brake assembly further comprises a return spring seat, a return spring and a return spring screw, wherein the return spring is positioned in the second shell, the return spring enables the annular piston to move from a braking position to a non-braking position, a plurality of second mounting holes are uniformly distributed on the side surface of the piston, the return spring seat is installed in the second mounting holes in an interference fit manner, the return spring screw penetrates through the return spring seat and is installed on the second shell, the return spring is sleeved on the return spring screw, one end of the return spring is propped against the return spring seat, and the other end of the return spring is propped against the return spring screw;

The travel of the return spring seat is limited by the return spring screw to be a first gap, the annular piston and the return spring seat are in interference fit and move together, and when the inner friction plate and the outer friction plate are in an unworn state, the displacement travel between the braking position and the non-braking position of the annular piston is not larger than the first gap; when the inner friction plate and the outer friction plate are worn, the annular piston and the return spring seat are still in interference fit and fixed after relative displacement is generated, and the return spring screw limits the stroke of the return spring seat to be a first clearance, so that the displacement stroke between the braking position and the non-braking position of the annular piston is the first clearance.

Preferably, the input assembly further comprises a parking brake assembly, the parking brake assembly comprises a parking brake mounting seat, a pull rod, a rotating shaft, a pressure plate, a plurality of annular second inner friction plates and a plurality of annular second outer friction plates, the parking brake mounting seat is fixedly connected with the first shell to form a cavity, the pressure plate can be mounted on the parking brake mounting seat in a smooth moving mode, the plurality of second outer friction plates are mounted in the cavity and are circumferentially and axially movably matched with one transmission shaft in the input assembly in a positioning mode, the plurality of second inner friction plates are alternately overlapped with one another through splines, the pull rod is in transmission connection or is fixedly connected with the rotating shaft, and the rotating shaft is rotatably mounted on the parking brake mounting seat and pushes the pressure plate to move in the rotating process so as to press the second inner friction plates and the second outer friction plates on the first shell.

Preferably, a plurality of pins which are uniformly distributed circumferentially and a plurality of second springs which are sleeved on the pins are further arranged, a plurality of second through holes which are uniformly distributed circumferentially are formed in the second outer friction plates, the pins penetrate through the second through holes in the plurality of second outer friction plates, the plurality of second springs are sequentially distributed between two adjacent second outer friction plates, two ends of each second spring are respectively propped against the two adjacent second outer friction plates, and then the two adjacent second outer friction plates are unfolded through the second springs, and the outer friction plates on one side are propped against the pressure plate.

Preferably, the rotating shaft is provided with a cam part, and in the rotating process of the rotating shaft, the cam part is matched with the pressure plate so that the pressure plate compresses the second inner friction plate and the second outer friction plate on the first shell.

Preferably, the parking brake device is further provided with a torsion spring seat and a first torsion spring, wherein the torsion spring seat is installed in the first installation hole and is in transmission connection with the rotating shaft, the torsion spring seat is arranged below the pull rod, and the first torsion spring is sleeved on the outer surface of the parking brake installation seat and is connected with the torsion spring seat.

The invention has the beneficial effects that:

1) The transmission structure of the drive axle is optimized through the technical scheme: the input shaft, the intermediate shaft, the first half shaft and the second half shaft are transversely distributed, the transmission structure of the drive axle is optimized, the occupied space of the drive axle is saved, and the volume of the drive axle is reduced.

2) The parking brake assembly of the drive axle is optimized through the technical scheme: the parking brake assembly is arranged on the side face of the input assembly, so that the space height occupied by the drive axle is reduced, and the structure of the drive axle is more reasonable;

in addition, the transmission level between the pull rod and the braking friction plate in the parking braking assembly is 1 level, namely, the transmission torque is large, and the labor is saved for operators.

3) The service brake assembly of the drive axle is optimized through the technical scheme: the first inner friction plate is arranged on the half shaft through the first shaft sleeve, so that the shape of the half shaft is simplified, the installation of the half shaft is facilitated, and the hub component is simple in structure;

in addition, through the cooperation of first outer friction disc, first internal friction disc, circlip and first axle sleeve, can accomplish the axial positioning of first axle sleeve.

Drawings

FIG. 1 is a schematic diagram of the drive axle transmission structure of the present invention;

FIG. 2 is a schematic diagram of the transmission structure of the input assembly of the present invention;

FIG. 3 is a schematic representation of the transmission structure of the service brake assembly of the present invention;

FIG. 4 is a schematic illustration of the transmission structure of the parking brake assembly of the present invention;

FIG. 5 is a cross-sectional view of the parking brake mount of the present invention;

FIG. 6 is a cross-sectional view of the torsion spring seat of the present invention;

FIG. 7 is a cross-sectional view of a spindle of the present invention;

FIG. 8 is a cross-sectional view of a second hub of the present invention;

fig. 9 is a cross-sectional view of a platen of the present invention.

Reference numerals illustrate: 2. an input assembly; 3. a service brake assembly; 4. a hub assembly; 101. a first housing; 102. a second housing; 103. a half shaft; 202. a differential case; 203. a first planetary gear; 204. a side gear; 206. an input shaft; 207. an intermediate shaft; 208. a first gear; 209. a second gear; 210. a motor; 301. a first sleeve; 302. a piston; 303. a first outer friction plate; 304. a first inner friction plate; 401. a second sleeve; 402. a hub member; 403. a first tapered roller bearing; 404. a first oil seal; 405. a second oil seal; 4013. a first blocking portion; 4014. a second blocking portion; 305. a circlip; 306. a first latch; 307. a first spring; 4011. a sleeve portion; 4012. a flange portion; 308. a return spring seat; 309. a return spring; 310. a return spring screw; 311. a first seal ring; 312. a second seal ring; 3101. a first flange; 211. a parking brake mount; 212. a pull rod; 213. a rotating shaft; 214. a pressure plate; 215. a second inner friction plate; 216. a second outer friction plate; 217. a pin shaft; 218. a second spring; 2131. a cam section; 2141. a sliding part; 219. torsion spring seat; 220. a first torsion spring; 221. a second latch; 222. a third seal ring; 223. a fourth seal ring; 2111. a fourth through hole; 2132. a second flange; 2191. a V-shaped groove; 2112. a first mounting hole; 2113. a third through hole; 2114. a cavity; 2115. and a second positioning hole.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element 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.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more, unless otherwise clearly defined.

In the present invention, unless specifically stated and limited otherwise, the terms "mounted," "connected," "coupled," "secured," and the like are to be construed broadly, and may be fixedly coupled, detachably coupled, or integrally coupled, for example; can be mechanically or electrically coupled; can be directly connected or indirectly connected through an intermediate medium, and can be communication between 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.

In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the present invention, the differential assembly is directed in an "inward" direction by the hub assembly and the differential assembly is directed in an "outward" direction by the hub assembly.

In the present invention, both "horizontal" and "vertical" are referenced to the orientation of FIG. 1.

The driving axle comprises an axle housing, an input assembly 2, two service brake assemblies 3, two half shafts 103 and two hub components 4, wherein the two half shafts 103 are coaxially distributed, the axle housing comprises a first housing 101 and two second housings 102 which are fixedly connected, the two second housings 102 are respectively positioned on the left side and the right side of the first housing 101, the service brake assemblies 3 are positioned in the second housings 102 and sleeved on the half shafts 103, the hub components 4 are arranged at the outer ends of the second housings 102 and are fixedly connected with the outer ends of the half shafts 103, and the input assembly 2 is arranged on the first housing 101;

as shown in fig. 2, the input assembly 2 includes a differential assembly including a differential case 202, a first planetary gear 203 and two side gears 204, the differential case 202 is mounted on the inside of the first case 101 and rotatable in the first case 101, the first planetary gear 203 is mounted inside the differential case 202 and rotatable following the differential case 202, the two side gears 204 are respectively located on the left and right sides of the inside of the differential case 202, the two side gears 204 are engaged with the first planetary gear 203, and the inner end of the half shaft 103 extends into the differential case 202 and is in driving connection with the side gears 204;

In this embodiment, the input assembly 2 further includes an input shaft 206, an intermediate shaft 207, a first gear 208 and a second gear 209 mounted on the first housing 101, where the input shaft 206 is in driving connection with the motor 210, the first gear 208 is sleeved on the intermediate shaft 207 and is in driving connection with the intermediate shaft 207, the first gear 208 is in driving fit with the shaft teeth of the input shaft 206, the second gear 209 is in driving fit with the shaft teeth of the intermediate shaft 207, the second gear 209 is fixedly connected with the differential housing 202, and the input shaft 206, the intermediate shaft 207 and the two half shafts 103 are all distributed transversely;

as shown in fig. 3, the service brake assembly 3 includes a first shaft sleeve 301, an annular piston 302, a plurality of annular first outer friction plates 303 and a plurality of annular first inner friction plates 304, the first shaft sleeve 301 is in driving fit with the half shaft 103 through an internal spline, the first outer friction plates 303 are in axially movable fit with the first housing 101 in a circumferential positioning manner, the first inner friction plates 304 are in axially movable fit with the first shaft sleeve 301 in a circumferential positioning manner, the plurality of annular first inner friction plates 304 and the first outer friction plates 303 are alternately stacked with each other, and the piston 302 is mounted on the second housing 102 and is movable between a braking position and a non-braking position;

The hub assembly 4 comprises a second shaft sleeve 401 and a hub piece 402, wherein the second shaft sleeve 401 is sleeved on the half shaft 103 and fixedly connected with the outer end of the second shell 102, and the hub piece 402 is fixedly connected with the half shaft 103;

wherein, when the service brake assembly 3 is in a braking state, the piston 302 moves to a braking position such that the plurality of first inner friction plates 304 and the first outer friction plates 303 abut and press against the second sleeve 401.

Through the transverse arrangement of the input shaft 206 and the output shaft, the transmission structure in the drive axle is effectively improved, so that the drive axle housing is reasonable in structure and small in volume, and the occupied space of the drive axle is reduced; in addition, a bearing plate is saved, so that the structure of parts of the drive axle is more simplified, and the cost is saved.

In the embodiment, two first tapered roller bearings 403 are further provided, the first tapered roller bearings are sleeved on the second shaft sleeve 401, and the outer surfaces of the tapered roller bearings are abutted against the inner surface of the hub member 402; further preferably, the second sleeve 401 is provided with a first blocking portion 4013 and a second blocking portion 4014 for preventing the tapered roller bearings from moving axially, wherein the first blocking portion 4013 is formed by a protrusion on the second sleeve 401, and the second blocking portion 4014 is detachably coupled with the second sleeve 401, so that the mounting of the two first tapered roller bearings 403 is facilitated.

In this embodiment, there is also provided a first oil seal 404 and a second oil seal 405, the first oil seal 404 being located between the second axle housing 401 and the hub member 402, the second oil seal 405 being located between the axle half 103 and the second axle housing 401.

In this embodiment, an elastic retainer ring 305 is further provided, an axial spline groove and a circumferential annular groove are provided on the outer surface of the first shaft sleeve 301, a plurality of first mounting grooves are provided on the inner side wall of the second housing 102, and the first outer friction plate 303 is clamped in the first mounting grooves; the first inner friction plates 304 are clamped in the spline grooves and are in transmission connection with the first shaft sleeve 301, and the circlip 305 is clamped in the annular groove and is positioned between any two adjacent first inner friction plates 304; the axial positioning of the first sleeve 301 is thus completed by the engagement of the first outer friction plate 303 with the first mounting groove, the engagement of the first inner friction plate 304 with the first outer friction plate 303, and the engagement of the first inner friction plate 304 with the circlip 305.

It is further preferred that the circlip 305 has a thickness less than the thickness of the first outer friction plate 303.

In this embodiment, a plurality of first pins 306 uniformly distributed along the circumference and a plurality of first springs 307 sleeved on the first pins 306 are further provided, a plurality of first through holes uniformly distributed along the circumference are provided on the first outer friction plate 303, one end of the first pins 306 passes through the first through holes on the plurality of first outer friction plates 303 and abuts against the second housing 102, the other end of the first pins 306 abuts against the second shaft housing 401, the plurality of first springs 307 are sequentially distributed between two adjacent first outer friction plates 303, and two ends of the first springs 307 abut against the two adjacent first outer friction plates 303 respectively, so that the two adjacent first outer friction plates 303 are separated by a certain distance through the first springs 307. The arrangement enables the two first outer friction plates 303 to be unfolded more thoroughly, and friction force or larger friction force between the first inner friction plates 304 and the first outer friction plates 303 in a non-braking state is avoided.

In this embodiment, as shown in fig. 8, the second sleeve 401 includes a sleeve portion 4011 and a flange portion 4012 which are integrally formed, the flange portion 4012 is fixedly mounted on the outer end surface of the second housing 102 by a plurality of fasteners, the other end of the first plug 306 abuts against the inner end surface of the flange portion 4012, and when the piston 302 moves to the braking position, the plurality of first inner friction plates 304 and the first outer friction plates 303 are pressed against the inner end surface of the flange portion 4012.

In this embodiment, the service brake assembly 3 further includes a return spring seat 308, a return spring 309 and a return spring screw 310 located in the second housing 102, where the return spring 309 moves the annular piston 302 from the braking position to the non-braking position, a plurality of second mounting holes are uniformly distributed on the side surface of the piston 302, the return spring seat 308 is mounted in the second mounting holes in an interference fit manner, the return spring screw 310 passes through the return spring seat 308 and is mounted on the second housing 102, the return spring 309 is sleeved on the return spring screw 310, and one end of the return spring 309 abuts against the return spring seat 308, and the other end abuts against the return spring screw 310.

The outer surface of the return spring seat 308 is a cylindrical surface and is in interference fit with the second mounting hole, which is worth noting that the outer surface of the return spring seat 308 may be in other shapes, such as a triangular prism, a cuboid, etc., the corresponding second mounting hole is in interference fit with the outer surface of the return spring seat 308, and the specific form is that the return spring seat 308 and the annular piston 302 can mutually drive each other to move, and when the first inner friction plate 304 and the first outer friction plate 303 are worn, the return spring screw 310 limits the travel of the return spring seat 308 to be a first gap, the annular piston 302 and the first outer friction plate 303 still have a gap, and the annular piston 302 can still axially move under the action of oil pressure until the end surface abuts against the first outer friction plate 303.

Specifically, the end surface of the annular piston 302 located at the outer side can be abutted against the first outer friction plate 303, the end surface of the annular piston 302 located at the inner side can be abutted against the first housing 101, a first annular groove and a second annular groove are formed in the circumferential side wall of the annular piston 302, and a first sealing ring 311 and a second sealing ring 312 are respectively arranged in the first annular groove and the second annular groove.

Specifically, the return spring screw 310 is provided with a first flange 3101, one end of the return spring 309 abuts against the first flange 3101, the other end abuts against the return spring seat 308, the distance between the first flange 3101 and the return spring seat 308 is a first gap, when the annular piston 302 moves from the non-braking position to the braking position abutting against the first outer friction plate 303, the first flange 3101 may abut against the return spring seat 308, so as to limit the travel of the return spring seat 308 to the first gap, in this embodiment, the first flange 3101 may be disc-shaped or may have another shape, only when the annular piston 302 moves from the non-braking position to the braking position abutting against the first outer friction plate 303, the first flange 3101 may abut against the return spring seat 308, in this embodiment, the first flange 3101 is preferably disc-shaped, and the disc diameter is greater than the inner diameter, so as to abut against the return spring seat 308.

When the friction plate is not worn and is in a non-braking state, the inner end surface of the annular piston 302 abuts against one of the mounting surfaces in the second housing 102, and in this embodiment, the name of the mounting surface in the second housing 102 is called a first mounting surface, the return spring seat 308 is in interference fit with the second mounting hole in the annular piston 302, and the end surface of the return spring seat 308 abuts against the first mounting surface, and in this state, the distance between the first flange 3101 on the return spring screw 310 and the return spring seat 308 is a first gap.

The oil cavity is filled with pressure oil, the annular piston 302 drives the return spring seat 308 to move from a non-braking position separated from the first outer friction plate 303 to a braking position abutting against the first outer friction plate 303 until the annular piston 302 reaches a braking point abutting against the first outer friction plate 303, the outer end face of the annular piston 302 abuts against the first outer friction plate 303, the inner end face of the annular piston is still flush with one end face of the return spring seat 308, the outer end face of the return spring seat 308 abuts against a first flange 3101 on the return spring screw 310, in this state, the distance between the return spring seat 308 and the first mounting face is a first gap, and the distance between the inner end face of the annular piston 302 and the first mounting face is also a first gap, namely, the displacement of the return spring seat 308 and the annular piston 302 is both the first gap.

When the first inner friction plate 304 and the first outer friction plate 303 are worn, the return spring screw 310 limits the travel of the return spring seat 308 to a first clearance, the annular piston 302 is still axially movable until the end face abuts against the first outer friction plate 303, when the annular piston 302 reaches a braking position abutting against the first outer friction plate 303, the inner end face of the annular piston 302 is no longer flush with the inner end face of the return spring seat 308, the inner end face of the return spring seat 308 protrudes inward relative to the inner end face of the annular piston 302 by a part, and the outer end face of the return spring seat 308 abuts against a first flange 3101 on the return spring screw 310, in this state, the distance between the return spring seat 308 and the first mounting face is a first clearance, and the distance between the inner end face of the annular piston 302 and the first mounting face is a second clearance, which is larger than the first clearance.

The oil chamber discharges the pressure oil, the return spring seat 308 moves away from the first inner friction plate 304 and the first outer friction plate 303 under the action of the return spring 309, and drives the annular piston 302 to move together to a non-braking state, in this process, the displacement of the return spring seat 308 and the annular piston 302 is a first gap, so that a third gap exists between the inner end surface of the annular piston 302 and the first mounting surface, the sum of the third gap and the first gap is a second gap, the inner end surface of the return spring seat 308 protrudes a part relative to the inner end surface of the annular piston 302, and the inner end surface of the return spring seat 308 still abuts against the first mounting surface, in this state, the distance between the first flange 3101 on the return spring screw 310 and the return spring seat 308 is the first gap.

It should be noted that, during the process that the annular piston 302 reaches the non-braking position separated from the first outer friction plate 303 from the braking point abutting against the first outer friction plate 303, no matter whether the first inner friction plate 304 and the first outer friction plate 303 have abrasion, the return spring seat 308 drives the annular piston 302 to move together in the direction away from the first inner friction plate 304 and the first outer friction plate 303, the moving distance is always the first gap under the limit of the first flange 3101 and the first mounting surface, that is, the return distance of the annular piston 302 is always the first gap, that is, when the annular piston 302 reaches the non-braking position separated from the first outer friction plate 303 next time from the braking position abutting against the first outer friction plate 303, the required displacement of the annular piston 302 is always the first gap, so that the purpose of compensating the abrasion of the first inner friction plate 304 and the first outer friction plate 303 is achieved, the braking distance is always kept unchanged during the use process, the braking effect is ensured, and the first inner friction plate 304 and the first friction plate 303 is more durable, and the first friction plate 304 is maintained and the first friction plate 303 is more durable.

In addition, as the wear of the first inner friction plate 304 and the first outer friction plate 303 increases, the braking position of the annular piston 302 is also continuously moved outwards, that is, the displacement distance of the inner first outer friction plate 303 is also continuously increased under the condition of ensuring the braking effect, but the elasticity between the inner first outer friction plate 303 and the inner first outer friction plate 303 is reduced along with the increase of the wear degree of the friction plates, so that the friction plates still can return to the initial position after the braking is finished by adding springs between the friction plates, and the phenomenon that the inner first outer friction plate 303 is not fully unfolded to cause a dead feeling in the driving process is avoided under the non-braking state.

In this embodiment, the input assembly 2 further includes a parking brake assembly as shown in fig. 4, where the parking brake assembly includes a parking brake mounting seat 211, a pull rod 212, a rotating shaft 213, a pressure plate 214, a plurality of annular second inner friction plates 215 and a plurality of annular second outer friction plates 216, where the parking brake mounting seat 211 is fixedly connected with the first housing 101 and forms a cavity 2114 together, the pressure plate 214 is mounted on the parking brake mounting seat 211 in a smooth and movable manner, the plurality of second outer friction plates 216 are mounted in the cavity 2114 and are axially movably matched in a circumferential positioning manner, the plurality of second inner friction plates 215 are alternately stacked with each other through splines and are axially movably matched with one transmission shaft in the input assembly 2 in a circumferential positioning manner, the pull rod 212 is in driving connection with the rotating shaft 213 or is fixedly connected with the second outer friction plates 216, and the rotating shaft 213 is rotatably mounted on the parking brake mounting seat 211 and pushes the second inner friction plates 215 and the second outer friction plates 216 to be pressed on the first housing 101 in a rotating process, so that the rotation of the transmission bridge 215 and the transmission shaft can not be completely rotated.

In this embodiment, as shown in fig. 5, the parking brake mounting seat 211 is provided with a vertical first mounting hole 2112, a lateral third through hole 2113 is provided on a side wall of the first mounting hole 2112, which is close to the first housing 101, the rotating shaft 213 is rotatably mounted in the first through hole, and the pressure plate 214 is laterally movably mounted in the third through hole 2113.

In this embodiment, the plurality of second inner friction plates 215 are axially movably matched with the input shaft 206 in a circumferential positioning manner through splines; in other embodiments, a plurality of second inner friction plates 215 are splined in circumferentially positioned axial clearance engagement with the intermediate shaft 207.

In this embodiment, a plurality of pins 217 uniformly distributed along the circumference and a plurality of second springs 218 sleeved on the pins 217 are further provided, the second outer friction plates 216 are provided with a plurality of second through holes uniformly distributed along the circumference, the pins 217 pass through the second through holes on the plurality of second outer friction plates 216, the plurality of second springs 218 are sequentially distributed between two adjacent second outer friction plates 216, and two ends of each second spring 218 respectively abut against the two adjacent second outer friction plates 216, so that the two adjacent second outer friction plates 216 are unfolded through the second springs 218 and the outer friction plates on one side abut against the pressure plate 214. This is because the rotation shaft 213 cannot bring the pressure plate 214 back to the initial position after braking is completed, and thus the pressure plate 214 is pushed back to the initial position by the action of the second spring 218, thereby releasing the braking state.

Further preferably, the first housing 101 is provided with a plurality of first positioning holes uniformly distributed along a circumference, the parking brake mounting seat 211 is provided with a plurality of second positioning holes 2115 uniformly distributed along a circumference, one end of the pin 217 passes through the plurality of second outer friction plates 216 and is inserted into the first positioning holes, and the other end of the pin 217 is inserted into the second positioning holes 2115.

In this embodiment, as shown in fig. 7, the rotating shaft 213 is provided with a cam portion 2131, and during the rotation of the rotating shaft 213, the cam portion 2131 cooperates with the pressure plate 214 such that the pressure plate 214 compresses the second inner friction plate 215 and the second outer friction plate 216 against the first housing 101.

Further preferably, the cam portion 2131 is formed by a groove on a side wall of the rotating shaft 213, and a distance between the bottom surface in the groove and the side wall of the rotating shaft 213 is gradually reduced, as shown in fig. 9, a sliding portion 2141 is disposed on an end surface of the platen 214 near the rotating shaft 213, and the sliding portion 2141 is clamped in the groove.

It should be noted that, by the cooperation of the cam portion 2131 and the sliding portion 2141, not only the pressure plate 214 may be moved, but also two degrees of freedom of the rotation shaft 213 in the vertical direction may be limited, that is, the rotation shaft 213 may be stably mounted on the parking brake mounting seat 211 by the cooperation of the cam portion 2131 and the sliding portion 2141.

In this embodiment, there are also a torsion spring seat 219 and a first torsion spring 220 as shown in fig. 6, where the torsion spring seat 219 is installed in the first installation hole 2112 and is in driving connection with the rotation shaft 213, the torsion spring seat 219 is located below the pull rod 212, and the first torsion spring 220 is sleeved on the outer surface of the parking brake installation seat 211 and is connected with the torsion spring seat 219. By this arrangement, the rotation shaft 213 can automatically return to the initial position under the action of the first torsion spring 220 after rotating.

Further preferably, at least one second pin 221 is further provided, the rotating shaft 213 is provided with a second flange 2132, a circle of V-shaped groove 2191 is provided on the side wall of the torsion spring seat 219, at least one fourth through hole 2111 is provided on the side wall of the first mounting hole 2112, the bottom end of the first through hole torsion spring seat 219 abuts against the second flange 2132, and the second pin 221 passes through the fourth through hole 2111 and abuts against the V-shaped groove 2191; by this arrangement, the torsion spring seat 219 is mounted on the parking brake mount 211, and the degree of freedom of the rotation shaft 213 in the vertical direction is further limited.

In this embodiment, a third sealing ring 222 is further provided, and the third sealing ring 222 is respectively abutted against the parking brake mounting seat 211 and the first housing 101, that is, the third sealing ring 222 is mainly used for sealing a gap between the parking brake mounting seat 211 and the first housing 101.

In this embodiment, a fourth sealing ring 223 is further provided, and the fourth sealing ring 223 is respectively abutted against the parking brake mounting seat 211 and the torsion spring seat 219, that is, the fourth sealing ring 223 is mainly used for sealing a gap between the parking brake mounting seat 211 and the torsion spring seat 219.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives, and variations may be made in the above embodiments by those skilled in the art without departing from the spirit and principles of the invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a transaxle, includes axle housing, input assembly (2), two service brake assemblies (3), two semi-axis (103) and two wheel hub subassemblies (4) of coaxial distribution, the axle housing includes fixed connection's first casing (101) and two second casings (102), two second casings (102) are located the left and right sides of first casing (101) respectively, service brake assemblies (3) are located second casing (102) and overlap and establish on semi-axis (103), wheel hub subassemblies (4) are installed in the outer end of second casing (102) and with the outer end fixed connection of semi-axis (103), input assembly (2) are installed on first casing (101);

the input assembly (2) comprises a differential assembly, the differential assembly comprises a differential shell (202), four first planet gears (203) and two side gears (204), the differential shell (202) is installed inside the first shell (101) and can rotate in the first shell (101), the first planet gears (203) are installed inside the differential shell (202) and can rotate along with the differential shell (202), the two side gears (204) are respectively positioned on the left side and the right side of the inside of the differential shell (202), the two side gears (204) are meshed with the four first planet gears (203), and the inner ends of the half shafts (103) extend into the differential shell (202) and are in transmission connection with the side gears (204);

It is characterized in that the method comprises the steps of,

the input assembly (2) further comprises an input shaft (206), an intermediate shaft (207), a first gear (208) and a second gear (209) which are arranged on the first shell (101), the input shaft (206) is in transmission connection with the motor (210), the first gear (208) is sleeved on the intermediate shaft (207) and in transmission connection with the intermediate shaft (207), the first gear (208) is in transmission fit with shaft teeth of the input shaft (206), the second gear (209) is in transmission fit with shaft teeth of the intermediate shaft (207), the second gear (209) is fixedly connected with the differential shell (202), and the input shaft (206), the intermediate shaft (207) and the two half shafts (103) are all transversely distributed;

the service brake assembly (3) comprises a first shaft sleeve (301), an annular piston (302), a plurality of annular first outer friction plates (303) and a plurality of annular first inner friction plates (304), the first shaft sleeve (301) is in transmission fit with the half shaft (103) through an internal spline, the first outer friction plates (303) are in circumferential positioning axial movable fit with the first shell (101), the first inner friction plates (304) are in circumferential positioning axial movable fit with the first shaft sleeve (301), a plurality of annular first inner friction plates (304) and a plurality of annular first outer friction plates (303) are alternately overlapped with each other, and the piston (302) is mounted on the second shell (102) and can move between a braking position and a non-braking position;

The hub assembly (4) comprises a second hub (401) and a hub piece (402), the second hub (401) is fixedly connected with the outer end of the second shell (102) and sleeved on the half shaft (103), and the hub piece (402) is fixedly connected with the half shaft (103);

wherein, when the service brake assembly (3) is in a braking state, the piston (302) moves to a braking position so that the plurality of first inner friction plates (304) and the first outer friction plates (303) are propped against and pressed against the second sleeve (401);

the input assembly (2) further comprises a parking brake assembly, the parking brake assembly comprises a parking brake mounting seat (211), a pull rod (212), a rotating shaft (213), a pressure plate (214), a plurality of annular second inner friction plates (215) and a plurality of annular second outer friction plates (216), the parking brake mounting seat (211) is fixedly connected with the first shell (101) and jointly forms a cavity (2114), the pressure plate (214) is mounted on the parking brake mounting seat (211) in a smooth moving mode, the plurality of second outer friction plates (216) are mounted in the cavity (2114) and are in circumferential positioning axial movable fit, the plurality of second inner friction plates (215) are in circumferential positioning axial movable fit with one transmission shaft in the input assembly (2) through splines, the plurality of second inner friction plates (215) and the second outer friction plates (216) are alternately stacked with each other, the pull rod (212) is in transmission connection or fixed connection with the rotating shaft (213), and the rotating shaft (213) is rotatably mounted on the parking brake mounting seat (211) and pushes the pressure plate (214) to move in the rotating process so as to press the second inner friction plates (215) and the first shell (101) tightly.

2. A drive axle according to claim 1, characterized in that two first tapered roller bearings (403) are provided, which first tapered roller bearings (403) are fitted over the second sleeve (401), the outer surfaces of the tapered roller bearings abutting the inner surface of the hub member (402).

3. A drive axle according to claim 1, characterized in that a first oil seal (404) and a second oil seal (405) are further provided, the first oil seal (404) being located between the second axle sleeve (401) and the hub member (402), the second oil seal (405) being located between the axle half shaft (103) and the second axle sleeve (401).

4. A drive axle according to claim 1, further comprising a circlip (305), wherein the outer surface of the first sleeve (301) is provided with an axial spline groove and a circumferential annular groove, the inner side wall of the second housing (102) is provided with a plurality of first mounting grooves, and the first outer friction plate (303) is clamped in the first mounting grooves; the first inner friction plates (304) are clamped in the spline grooves and are in transmission connection with the first shaft sleeve (301), and the circlip (305) is clamped in the annular groove and positioned between any two adjacent first inner friction plates (304).

5. A drive axle according to claim 1, further comprising a plurality of first pins (306) and a plurality of first springs (307) sleeved on the first pins (306), wherein a plurality of first through holes are formed in the first outer friction plates (303), one ends of the first pins (306) penetrate through the first through holes in the plurality of first outer friction plates (303) and abut against the second housing (102), the other ends of the first pins (306) abut against the second shaft sleeve (401), the plurality of first springs (307) are sequentially distributed between two adjacent first outer friction plates (303), and two ends of the first springs (307) abut against the two adjacent first outer friction plates (303) respectively, so that the two adjacent first outer friction plates (303) are unfolded through the first springs (307).

6. A drive axle according to claim 1, wherein the service brake assembly (3) further comprises a return spring seat (308), a return spring (309) and a return spring screw (310) in the second housing (102), wherein the return spring (309) moves the annular piston (302) from the braking position to the non-braking position, a plurality of second mounting holes are uniformly distributed on the side surface of the piston (302), the return spring seat (308) is mounted in the second mounting holes in an interference fit manner, the return spring screw (310) passes through the return spring seat (308) and is mounted on the second housing (102), the return spring (309) is sleeved on the return spring screw (310), one end of the return spring (309) is abutted against the return spring seat (308), and the other end is abutted against the return spring screw (310);

the return spring screw (310) limits the travel of the return spring seat (308) to be a first clearance, the annular piston (302) and the return spring seat (308) are in interference fit and jointly move, and when the inner friction plate and the outer friction plate are in an unworn state, the displacement travel between a braking position and a non-braking position of the annular piston (302) is not greater than the first clearance; when the inner friction plate and the outer friction plate are worn, the annular piston (302) and the return spring seat (308) are still in interference fit and fixed after relative displacement, and the return spring screw (310) limits the stroke of the return spring seat (308) to be a first clearance, so that the displacement stroke between the braking position and the non-braking position of the annular piston (302) is the first clearance.

7. The driving axle according to claim 1, further comprising a plurality of pins (217) and a plurality of second springs (218) sleeved on the pins (217), wherein the second outer friction plates (216) are provided with a plurality of second through holes, the pins (217) penetrate through the second through holes of the plurality of second outer friction plates (216), the plurality of second springs (218) are sequentially distributed between the two adjacent second outer friction plates (216), two ends of each second spring (218) are respectively abutted against the two adjacent second outer friction plates (216), and the two adjacent second outer friction plates (216) are unfolded through the second springs (218) and are abutted against the pressure plate (214).

8. A drive axle according to claim 1, characterized in that the shaft (213) is provided with a cam part (2131), the cam part (2131) cooperating with the pressure plate (214) during rotation of the shaft (213) such that the pressure plate (214) compresses the second inner friction plate (215) and the second outer friction plate (216) against the first housing (101).

9. The drive axle according to claim 1, further comprising a torsion spring seat (219) and a first torsion spring (220), wherein the torsion spring seat (219) is mounted in the first mounting hole (2112) and is in transmission connection with the rotation shaft (213), the torsion spring seat (219) is located below the pull rod (212), and the first torsion spring (220) is sleeved on the outer surface of the parking brake mounting seat (211) and is connected with the torsion spring seat (219).