CN112223956A

CN112223956A - Wet-type axle and box integrated drive axle for forklift

Info

Publication number: CN112223956A
Application number: CN202011104315.2A
Authority: CN
Inventors: 罗红平; 徐胜军; 金刚强
Original assignee: Zhejiang Jindao Technology Co ltd
Current assignee: Zhejiang Jindao Technology Co ltd
Priority date: 2020-10-15
Filing date: 2020-10-15
Publication date: 2021-01-15

Abstract

The invention discloses a wet axle box integrated drive axle for a forklift, which comprises an axle housing, an input assembly, two service brake assemblies, two coaxial half shafts and two hub assemblies, wherein the axle housing comprises a first shell and two second shells which are fixedly connected, the two second shells are respectively positioned at the left side and the right side of the first shell, the service brake assemblies are positioned in the second shells and sleeved on the half shafts, the hub assemblies are arranged at the outer ends of the second shells and fixedly connected with the outer ends of the half shafts, the input assembly is arranged on the first shell and 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

Wet-type axle and box integrated drive axle for forklift

Technical Field

The invention relates to the technical field of transmission of engineering machinery, in particular to a wet-type axle and box integrated drive axle for a forklift.

Background

As is known, the working conditions of the engineering machinery are relatively severe, at present, the market of the axle products of the domestic engineering machinery mainly uses a dry brake drive axle, and for example, chinese patent publication No. CN202272694U discloses a dry brake type internal combustion balance weight type forklift. CN203496676U discloses an integrative transmission of axle case for electric fork-lift truck, including axle housing, derailleur, transaxle and axle arm subassembly. CN204567140U discloses an axle box integral type speed reduction transmission on engineering machinery such as electric fork truck, carrier, including left transaxle shell, right transaxle shell, one-level speed reduction subassembly, second grade speed reduction subassembly, drive axle and axle arm subassembly.

However, in the prior art, a wet brake drive axle has been applied to a forklift, and for example, chinese patent publication No. CN107265354A discloses a forklift driving and parking integrated wet brake drive axle, which includes an input assembly, an axle housing, a first half shaft, a second half shaft, a spline housing, a fixed gear ring, and a first brake assembly and a second brake assembly located in the axle housing.

However, those skilled in the art find that the above-mentioned driving axle has the following disadvantages:

1) the power input of the existing wet brake drive axle is input into the drive axle through an engine through a gearbox and a transmission shaft, and a wet axle box integrated drive axle which takes a motor or a hydraulic motor as a power source is not provided;

2) the dry type brake driving axle adopts external dry type brake, which causes the dry type brake driving axle to be greatly influenced by the environmental factors such as moisture, freezing, dust and the like, the brake performance is unstable and the service life is short.

Disclosure of Invention

The first purpose of the present invention is to solve the above problems of the drive axle, and to provide a wet axle and box integrated drive axle for a forklift truck using a motor as a power source, wherein a transmission case is transversely provided with two-stage parallel shaft transmission, and a hub uses planetary transmission, so as to obtain a wet axle and box integrated drive axle with a large transmission ratio, a small space occupation, and a compact structure. In addition, wet braking is adopted for parking braking and service braking, so that the braking performance is improved, and the brake can adapt to special severe working conditions.

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

a wet-type axle box integrated drive axle for a forklift comprises an axle housing, an input assembly, two service brake assemblies, two coaxially distributed half shafts and two wheel hub assemblies, wherein the axle housing comprises a first shell, an end cover and two second shells which are fixedly connected, the two second shells are respectively positioned at the left side and the right side of the first shell and the end cover, the service brake assemblies are positioned in the second shells and sleeved on the half shafts, the wheel hub assemblies are arranged at the outer ends of the second shells and are in transmission fit with the outer ends of the half shafts, and the input assembly is arranged on the first shell and the end cover;

the input assembly comprises a differential assembly, the differential assembly comprises a differential shell, a first planetary gear and two half axle gears, the differential shell is arranged in the first shell and can rotate in the first shell, the first planetary gear is arranged in the differential shell and can rotate along with the differential shell, the two half axle gears are respectively positioned at the left side and the right side of the interior of the differential shell, the two half axle gears are both meshed with the first planetary gear, and the inner ends of the half axles extend into the differential shell and are in transmission connection with the half axle gears; the improvement which is made is that;

the input assembly further comprises an input shaft, an intermediate shaft, a first gear and a second gear, wherein the input shaft, the intermediate shaft, the first gear and the second gear are mounted on the first shell, the input shaft is in transmission connection with the motor, the first gear is sleeved on the intermediate shaft and is in transmission connection with the intermediate shaft, the first gear is in transmission fit with shaft teeth of the input shaft, the second gear is in transmission fit with shaft teeth of 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 service brake assembly comprises an annular piston, a plurality of annular first outer friction plates and a plurality of annular first inner friction plates, the first outer friction plates are in circumferential positioning axial movable fit with the first shell, the first inner friction plates are in circumferential positioning axial movable fit with the half shaft through splines, the plurality of annular first inner friction plates and the plurality of annular first outer friction plates are alternately overlapped with each other, the piston is positioned on the inner sides of the plurality of first inner friction plates and the plurality of first outer friction plates, and the piston is installed on the second shell and can move between a braking position and a non-braking position;

the hub component comprises a gear ring, a hub piece, a planet wheel and a planet carrier, the gear ring is fixedly arranged on the second shell and compresses the pressure bearing plate, the hub piece is arranged on the planet carrier and is in transmission connection with the planet carrier, the planet wheel is respectively meshed with a half shaft and the inner teeth of the gear ring, and the planet carrier and the planet wheel form an epicyclic gear train together;

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 and pressed on the hub component.

Preferably, the hub component further comprises a bearing plate, the bearing plate is pressed by the gear ring on the second shell, the bearing plate and the piston are respectively located on the inner side and the outer side of the first inner friction plate and the first outer friction plate, and when the service brake assembly is in a braking state, the piston moves to a braking position to enable the first inner friction plates and the first outer friction plates to abut against and press the bearing plate.

Preferably, a locking nut and two first tapered roller bearings are further arranged, a first annular bulge is further arranged on the inner side wall of the gear ring, inner rings of the two first tapered roller bearings are sleeved on the hub piece, outer rings of the two first tapered roller bearings are matched with the hole in the inner side of the gear ring, and the two first tapered roller bearings are respectively located at the inner end and the outer end of the first annular bulge and abut against the first annular bulge; the locking nut is in threaded fit with the hub piece, enables the planet carrier to abut against the inner ring of the first tapered roller bearing positioned on the inner side, and locks the planet carrier and the hub piece.

Preferably, a locking screw is further provided, and the locking screw is fixedly arranged on the planet carrier and used for limiting the rotation of the locking nut.

Preferably, the planet carrier further comprises a rotating part, the rotating part extends into the planetary gear, and a needle bearing is further arranged, and the needle bearing is sleeved on the rotating part and abuts against the inner side wall of the planetary gear;

still be equipped with a circlip and a gasket for the second shaft, still be equipped with a first annular groove on the rotation portion, circlip is located first annular groove for the second shaft, the gasket is located between circlip and the planet wheel for the second shaft, planet wheel both ends face offsets with planet carrier and gasket respectively.

Preferably, the service brake assembly further comprises a return spring seat, a return spring and a return spring screw which are positioned in the second shell, the return spring enables the annular piston to move 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, the return spring seat is mounted in the second mounting holes in an interference fit manner, the return spring screw penetrates through the return spring seat and is mounted on the second shell, the return spring is sleeved on the return spring screw, one end of the return spring abuts against the return spring seat, and the other end of the return spring abuts against the return spring screw;

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

Preferably, the input assembly further comprises a parking brake assembly, the parking brake assembly comprises a parking brake mounting seat, a hand brake swing arm, 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 installed on the parking brake installation seat in a smooth moving mode, the plurality of second outer friction plates are installed in the cavity and are in circumferential positioning axial movable fit, the plurality of second inner friction plates are in circumferential positioning axial movable fit with the input shaft of the input assembly through splines, the plurality of second inner friction plates and the plurality of second outer friction plates are alternately overlapped with each other, the hand brake swing arm is in transmission connection or fixed connection with the rotating shaft, the rotating shaft is rotatably installed on the parking brake installation seat and pushes the pressure plate to move in the rotating process, and therefore the second inner friction plate and the second outer friction plate are pressed on the first shell.

Preferably, the spring pressing device is further provided with a plurality of pin shafts which are uniformly distributed in the circumferential direction and a plurality of second springs which are sleeved on the pin shafts, a plurality of second through holes which are uniformly distributed in the circumferential direction are formed in the second outer friction plates, the pin shafts penetrate through the second through holes in the plurality of second outer friction plates, the plurality of second springs are sequentially distributed between the two adjacent second outer friction plates, two ends of each second spring respectively abut against the two adjacent second outer friction plates, and therefore the two adjacent second outer friction plates are separated through the second springs, and the outer friction plates on one side abut against the pressure plate.

Preferably, the rotating shaft is provided with a groove portion, and in the rotating process of the rotating shaft, the groove portion is matched with the pressure plate to enable the pressure plate to move in a reciprocating mode in the left-right direction, so that the second inner friction plate and the second outer friction plate are pressed on the first shell.

As preferred, still be equipped with axle sleeve and first torsional spring, the axle sleeve cover is established and is installed in the pivot and be located the below of manual brake swing arm, the lateral wall of axle sleeve offsets with the inside wall of first mounting hole, first torsional spring cover is established and is installed in the exterior of parking brake mount pad, and first torsional spring one end card is in the recess of parking brake mount pad, and the other end inserts the manual brake swing arm downthehole.

The invention has the beneficial effects that:

1) the transmission structure of the wet brake drive axle is optimized through the technical scheme: the input shaft, the intermediate shaft and the two half shafts are transversely distributed, so that the transmission structure of the wet brake drive axle is optimized, the occupied space of the wet brake drive axle is saved, and the volume of the wet brake drive axle is reduced.

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

in addition, the parking brake assembly is arranged at an input stage, and the parking brake is small in size and compact in structure due to the fact that the torque of the transmission system is amplified.

3) The service brake assembly of the wet brake drive axle is optimized through the technical scheme, the half shaft is matched with the inner friction plate and the planetary gear, and the structure is simple and easy to disassemble, assemble and maintain.

Drawings

FIG. 1 is a schematic view of a transmission structure of a wet axle box integrated drive axle for a forklift truck;

FIG. 2 is a schematic view of the drive configuration of the input assembly of the present invention;

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

FIG. 4 is a schematic diagram 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 a spindle of the present invention;

FIG. 7 is a schematic view of the installation of the spindle and the swing arm of the hand brake of the present invention;

FIG. 8 is a schematic illustration of the parking brake assembly of the present invention in an unbraked condition;

FIG. 9 is a cross-sectional view taken at A-A of FIG. 8;

FIG. 10 is a schematic illustration of the parking brake assembly of the present invention in a braking condition;

fig. 11 is a sectional view at B-B in fig. 10.

Description of reference numerals: 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; 105. an end cap; 202. a differential housing; 203. a first planetary gear; 204. a half shaft gear; 206. An input shaft; 207. an intermediate shaft; 208. a first gear; 209. a second gear; 210. a motor; 301. a pressure bearing plate; 302. A piston; 303. a first outer friction plate; 304. a first inner friction plate; 401. a ring gear; 402. a hub member; 403. a first tapered roller bearing; 404. a first oil seal; 405. a planet wheel; 406. a planet carrier; 407. locking the nut; 408. locking the screw; 409. a circlip for the second shaft; 410. a needle bearing; 305. a circlip for the first shaft; 306. a mandrel; 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 mounting seat; 212. a hand brake swing arm; 213. a rotating shaft; 214. a platen; 215. a second inner friction plate; 216. a second outer friction plate; 217. a pin shaft; 218. a second spring; 2131. a groove part; 219. a shaft sleeve; 220. A first torsion spring; 221. a second bolt; 222. a third seal ring; 223. a fourth seal ring; 2111. a fourth via hole; 2132. A circlip for the third shaft; 2112. a first mounting hole; 2113. a third through hole; 2114. a cavity; 2115. a second positioning hole; 224. and a fifth sealing ring.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for the purpose of facilitating the description of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

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

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "coupled," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably coupled, or integrally coupled; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected 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 specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, and that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, a first feature being "on," "above" and "over" a second feature includes the first feature being directly on and obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the present invention, the direction from the hub assembly toward the differential assembly is "in" and the direction from the differential assembly toward the hub assembly is "out".

In the present invention, "lateral" and "vertical" are both based on the orientation in fig. 1.

A wet axle box integrated drive axle for a forklift comprises an axle housing, an input assembly 2, two service brake assemblies 3, two coaxially distributed half shafts 103 and two hub assemblies 4, wherein the axle housing comprises a first shell 101, an end cover 105 and two second shells 102 which are fixedly connected, the two second shells 102 are respectively positioned at the left side and the right side of the first shell 101 and the end cover 105, the service brake assemblies 3 are positioned in the second shells 102 and are sleeved on the half shafts 103, the hub assemblies 4 are arranged at the outer ends of the second shells 102 and are in transmission fit with the outer ends of the half shafts 103, and the input assembly 2 is arranged on the first shell 101 and the end cover;

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 can rotate in the first case 101, the first planetary gear 203 is mounted inside the differential case 202 and can rotate along with the differential case 202, the two side gears 204 are respectively located at the left and right sides of the inside of the differential case 202, the two side gears 204 are both meshed with the first planetary gear 203, and the inner ends of the half shafts 103 extend into the differential case 202 and are in transmission coupling with the side gears 204;

in the present 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, the input shaft 206 is in transmission coupling with the motor 210, the first gear 208 is sleeved on the intermediate shaft 207 and is in transmission coupling with the intermediate shaft 207, the first gear 208 is in transmission engagement with shaft teeth of the input shaft 206, the second gear 209 is in transmission engagement with 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 laterally distributed;

as shown in fig. 3, the service brake assembly 3 includes 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 outer friction plates 303 are circumferentially positioned and axially movably matched with the first shell 101, the first inner friction plates 304 are circumferentially positioned and axially movably matched with the half shaft 103 through splines, the plurality of annular first inner friction plates 304 and the plurality of annular first outer friction plates 303 are alternately stacked on each other, the piston 302 is positioned at the inner sides of the plurality of first inner friction plates 304 and the plurality of first outer friction plates 303, 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 gear ring 401, a hub member 402, planet wheels 405 and a planet carrier 406, wherein the gear ring 401 is fixedly mounted on the second shell 102 and presses against the pressure bearing plate 301, the hub member 402 is mounted on the planet carrier 406 and is in transmission connection with the planet carrier 406, the planet wheels 405 are respectively meshed with the half shafts 103 and are internally meshed with the gear ring 401, and the planet carrier 406 and the planet wheels 405 jointly form an epicyclic gear train;

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 hub component 4.

So set up, optimized the transmission structure of wet brake transaxle: the input shaft, the intermediate shaft and the two half shafts are transversely distributed, so that the transmission structure of the wet brake drive axle is optimized, the occupied space of the wet brake drive axle is saved, and the volume of the wet brake drive axle is reduced;

the parking brake assembly of the wet brake drive axle is optimized: the parking brake assembly is arranged on the side surface of the input assembly, so that the space height occupied by the wet brake drive axle is reduced, and the structure of the wet brake drive axle is more reasonable;

In this embodiment, the hub assembly 4 further includes a pressure bearing plate 301, the ring gear 401 presses the pressure bearing plate against the second housing, the pressure bearing plate 301 and the piston 302 are respectively located at the inner side and the outer side of the first inner friction plate 304 and the first outer friction plate 303, and when the service brake assembly 3 is in the braking state, the piston 302 moves to the braking position so that the plurality of first inner friction plates 304 and the first outer friction plates 303 abut against each other and press against the pressure bearing plate 301.

In this embodiment, a locking nut 407 and two first tapered roller bearings 403 are further provided, the inner side wall of the gear ring is further provided with a first annular protrusion, the two first tapered roller bearings 403 are sleeved on the hub member 402, outer rings of the two first tapered roller bearings 403 abut against the inner side wall of the gear ring 401, and the two first tapered roller bearings 403 are respectively located at the inner end and the outer end of the first annular protrusion and abut against the first annular protrusion; the lock nut 407 is screwed to the hub member and locks the carrier 406 against the first tapered roller bearing 403 on the inner side; thus, the mounting of the carrier 406 to the hub member is completed, and the axial play of the carrier 406 and the hub member can be effectively prevented.

Further preferably, a locking screw 408 is further provided, and the locking screw 408 is fixedly mounted on the planet carrier 406 and is used for limiting the rotation of the locking nut 407.

In this embodiment, the planet carrier 406 further includes a rotating portion, the rotating portion extends into the planetary gear, and a needle bearing 410 is further disposed, and the needle bearing 410 is sleeved on the rotating portion and abuts against an inner hole of the planetary gear.

Preferably, a second shaft circlip 409 and a gasket are further arranged, a first annular groove is further arranged on the rotating part, the second shaft circlip 409 is located in the first annular groove, the gasket is located between the second shaft circlip 409 and the planet wheel 405, and the inner end surface and the outer end surface of the planet wheel respectively abut against the planet carrier 406 and the gasket; in this way, the planetary gear can be prevented from axially shifting.

In this embodiment, two first oil seals 404 are also provided, the two first oil seals 404 being disposed side by side and between the ring gear 401 and the hub member 402.

In this embodiment, two first shaft circlips 305 are further provided, and two second annular grooves are further provided on the axle shaft, the two first shaft circlips 305 are respectively located in the two second annular grooves, and the two first shaft circlips 305 are used for limiting the axial play of the axle shaft.

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, which are located in the second housing 102, the return spring 309 enables the annular piston 302 to move 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 penetrates 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 of the return spring 309 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, and it should be noted that the outer surface of the return spring seat 308 may also be in other shapes, such as a prism, a cuboid, etc., and the corresponding second mounting hole may be in interference fit with the outer surface of the return spring seat 308, specifically, the return spring seat 308 and the annular piston 302 may be mutually driven 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 stroke 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 may still axially move under the action of oil pressure until the end surface abuts against the first outer friction plate 303.

Specifically, the end face of the annular piston 302 located on the outer side can abut against the first outer friction plate 303, the end face of the annular piston 302 located on the inner side can abut against the first casing 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, the return spring 309 abuts against the first flange 3101 at one end and the return spring seat 308 at the other end, the distance between the first flange 3101 and the return spring seat 308 is a first clearance, when the annular piston 302 moves from the non-braking position to the braking position against the first outer friction plate 303, the first flange 3101 may abut the return spring seat 308, thereby limiting the travel of the return spring seat 308 to a first clearance, in this embodiment, the first flange 3101 may be disk-shaped or have other shapes, and only when the annular piston 302 moves from the non-braking position to the braking position 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 disk-shaped with a diameter greater than the inner diameter of the spring seat 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 a mounting surface in the second housing 102, for convenience of confirmation 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 one 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.

When pressurized oil enters the oil cavity, the annular piston 302 drives the return spring seat 308 to move from the non-braking position where the first outer friction plate 303 is separated to the braking position where the return spring seat abuts against the first outer friction plate 303 until the annular piston 302 reaches the braking point where the annular piston abuts against the first outer friction plate 303, the outer end surface of the annular piston 302 abuts against the first outer friction plate 303, the inner end surface of the annular piston 302 is still flush with one end surface of the return spring seat 308, and the outer end surface of the return spring seat 308 abuts against the first flange 3101 on the return spring screw 310.

When the first inner friction plate 304 and the first outer friction plate 303 are worn, the return spring screw 310 limits the stroke of the return spring seat 308 to a first clearance, the annular piston 302 can still axially move until the end surface 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 surface of the annular piston 302 is no longer flush with the inner end surface of the return spring seat 308, the inner end surface of the return spring seat 308 protrudes inwards by a part relative to the inner end surface of the annular piston 302, the outer end surface of the return spring seat 308 abuts against the first flange 3101 on the return spring screw 310, and in this state, the distance between the return spring seat 308 and the first mounting surface is a first clearance, the distance between the inner end surface of the annular piston 302 and the first mounting surface is a second clearance, and the second clearance is larger than the first clearance.

Pressure oil is discharged in the oil cavity, 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 the annular piston 302 is driven to move together to a non-braking state, in the process, the displacement of the return spring seat 308 and the displacement of the annular piston 302 are both first clearances, so that a third clearance exists between the inner end surface of the annular piston 302 and the first mounting surface, the sum of the third clearance and the first clearance is a second clearance, the inner end surface of the return spring seat 308 protrudes partially 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, and in the state, the distance between the first flange 3101 on the return spring screw 310 and the return spring seat 308 is the first clearance.

It should be noted that, in 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 are worn or not, 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 a 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 a first gap, that is, when the annular piston 302 reaches the braking position of the annular piston 302 abutting against the first outer friction plate 303 from the non-braking position separated from the first outer friction plate 303, the displacement required by the annular piston 302 is always the first gap, so as to achieve the purpose of compensating the wear of the first inner friction plate 304 and the first outer friction plate 303, the travel of the brake pedal is kept unchanged all the time in the use process of the brake assembly, and the brake effect is ensured.

In this embodiment, the input assembly 2 further includes a parking brake assembly as shown in fig. 4, the parking brake assembly includes a parking brake mounting seat 211, a hand brake swing arm 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 housing 101 and jointly forms a cavity 2114, the pressure plate 214 is smoothly and movably mounted on the parking brake mounting seat 211, the plurality of second outer friction plates 216 are mounted in the cavity 2114 and are circumferentially and axially movably matched, the plurality of second inner friction plates 215 are axially and movably matched with a circumferential positioning of a rotating shaft in the input assembly 2 through splines, the plurality of second inner friction plates 215 and the plurality of second outer friction plates 216 are alternately stacked, the hand brake swing arm 212 is in transmission connection or fixed connection with the rotating shaft 213, the rotating shaft 213 is rotatably mounted on the parking brake mounting seat 211 and pushes the pressure plate 214 to move during rotation, so as to press the second inner friction plate 215 and the second outer friction plate 216 against the first housing 101, and further to prevent the transmission shaft in the wet brake driving axle in transmission connection with the second inner friction plate 215 from rotating, i.e. to complete the parking brake.

It is noted that the drive shaft may be either the input shaft 206 or the intermediate shaft 207.

In this embodiment, as shown in fig. 5, a vertical first installation hole 2112 is formed in the parking brake installation seat 211, a horizontal third through hole 2113 is formed in a side wall of the first installation hole 2112 close to the first housing 101, the rotating shaft 213 is rotatably installed in the first through hole, and the pressure plate 214 is transversely movably installed in the third through hole 2113.

In the present embodiment, a plurality of second inner friction plates 215 are axially movably engaged 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 and axially movably engaged with the intermediate shaft 207 in a circumferentially oriented manner.

In this embodiment, a plurality of pin shafts 217 uniformly distributed in a circumferential direction and a plurality of second springs 218 sleeved on the pin shafts 217 are further provided, a plurality of second through holes uniformly distributed in a circumferential direction are provided on the second outer friction plates 216, the pin shafts 217 penetrate through the second through holes on the second outer friction plates 216, the 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 plate on one side abuts against the pressure plate 214. This is because the pressure plate 214 is pushed back to the initial position by the second spring 218 after braking is completed, and the braking state is released, and at the same time, the second outer friction plate is rotated, and the gap between the second outer friction plate and the pressure plate is uniform and completely separated due to the second spring, so that the belt loss is reduced, and heat generation is reduced.

Preferably, a plurality of first positioning holes are formed in the first housing 101 and are uniformly distributed circumferentially, a plurality of second positioning holes 2115 are formed in the parking brake mounting seat 211 and are uniformly distributed circumferentially, one end of the pin 217 penetrates 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, a groove portion 2131 is provided on the rotating shaft 213, and during the rotation of the rotating shaft 213, the pressure plate reciprocates in the left-right direction by the cooperation between the groove portion and the pressure plate, so as to press the second inner friction plate and the second outer friction plate against the first housing; specifically, when the bottom of the groove 2131 is engaged with the pressure plate 214, the parking brake is in a released state, and when the groove 2131 is disengaged from the pressure plate 214, the parking brake is in a braked state.

In other embodiments, the rotating shaft 213 may further include a cam portion, and during the rotation of the rotating shaft 213, the pressure plate reciprocates in the left-right direction by the engagement of the groove portion and the pressure plate, thereby pressing the second inner friction plate and the second outer friction plate against the first housing.

In this embodiment, still be equipped with axle sleeve 219 and first torsion spring 220, axle sleeve 219 cover is established and is installed in the pivot and be located the below of manual brake swing arm, the lateral wall of axle sleeve offsets with the inside wall of first mounting hole, first torsion spring 220 cover is established on parking brake mount pad 211, and first torsion spring one end card is in the recess of parking brake mount pad, and the other end inserts in the manual brake swing arm downthehole, so sets up, can make the parking handle loosen the back, can be under the effect of first torsion spring 220, and the manual brake swing arm is automatic to return to initial position.

Further preferably, at least one second bolt 221 is further provided, a third circlip 2132 for the shaft is arranged on the rotating shaft 213, a circle of V-shaped groove is arranged on the side wall of the shaft sleeve 219, at least one fourth through hole 2111 is arranged on the side wall of the first mounting hole 2112, the bottom end of the first through hole shaft sleeve 219 abuts against the third circlip 2132 for the shaft, and the second bolt 221 passes through the fourth through hole 2111 and abuts against the V-shaped groove; with this arrangement, the shaft sleeve 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 restricted.

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

In the present embodiment, a fourth seal ring 223 is further provided, and the fourth seal ring 223 abuts against the parking brake mounting seat 211 and the sleeve 219, that is, the fourth seal ring 223 is mainly used for sealing a gap between the parking brake mounting seat 211 and the sleeve 219.

In this embodiment, a fifth seal ring 224 is further provided, and the fifth seal ring 224 respectively abuts against the rotating shaft 213 and the shaft sleeve 219, that is, the fifth seal ring 213 is mainly used for a gap between the rotating shaft 213 and the shaft sleeve 219.

In this embodiment, as shown in fig. 7, the handbrake swing arm 212 and the rotating shaft 213 are connected by a small-module spline and locked by a bolt. Therefore, the angle between the rotating shaft 213 and the swing arm can be adjusted at will by adopting the small module spline, and the installation on the whole vehicle is convenient.

It should be noted that, as shown in fig. 8-11, after the handbrake swing arm 212 is released, the handbrake swing arm 212 returns to the original position under the action of the torsion spring, and at this time, the second inner friction plate 215 and the second outer friction plate 216 are separated from each other under the action of the second springs 218 until the pressing plate 214 is attached to the plane in the groove portion 2131, which is the position shown in fig. 8 and 9, and at this time, the parking brake of the vehicle is released;

when the hand brake swing arm 212 is tightened, the hand brake swing arm 212 rotates under the action of tension, the rotating shaft 213 is driven to rotate, the pressing plate 214 is pushed to move leftwards, after the hand brake swing arm rotates for a certain angle, the positions shown in fig. 10 and 11 are reached, the second inner friction plate 215 and the second outer friction plate 216 are pressed by the pressing plate 214, and at the moment, the vehicle is in a parking brake state.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean 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 invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. 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 is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. The utility model provides a fork truck is with integrative transaxle of wet-type axle case, includes axle housing, input assembly (2), two service brake assemblies (3), two coaxial distribution's semi-axis (103) and two wheel hub subassemblies (4), the axle housing includes fixed connection's first casing (101), end cover (105) and two second casings (102), two second casings (102) are located the left and right sides of first casing (101) and end cover (105) respectively, service brake assembly (3) are located second casing (102) and overlap and establish on semi-axis (103), wheel hub subassembly (4) are installed in the outer end of second casing (102) and are in transmission fit with the outer end of semi-axis (103), input assembly (2) are installed on first casing (101) and end cover (105);

the input assembly (2) comprises a differential assembly, the differential assembly comprises a differential shell (202), a first planetary gear (203) and two half-shaft (103) gears, the differential shell (202) is installed inside the first shell (101) and can rotate in the first shell (101), the first planetary gear (203) is installed inside the differential shell (202) and can rotate along with the differential shell (202), the two half-shaft (103) gears are respectively located on the left side and the right side inside the differential shell (202), the two half-shaft (103) gears are both meshed with the first planetary gear (203), and the inner ends of the half shafts (103) extend into the differential shell (202) and are in gear transmission connection with the half shafts (103); it is characterized in that;

the input assembly (2) further comprises an input shaft (206), an intermediate shaft (207), a first gear (208) and a second gear (209), wherein the input shaft (206) is mounted on the first shell (101), the input shaft (206) is in transmission connection with a motor (210), the first gear (208) is sleeved on the intermediate shaft (207) and is 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 transversely distributed;

the service brake assembly (3) comprises 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 outer friction plates (303) are circumferentially positioned and axially movably matched with the first shell (101), the first inner friction plates (304) are circumferentially positioned and axially movably matched with the half shaft (103) through splines, the plurality of annular first inner friction plates (304) and the first outer friction plates (303) are alternately overlapped with each other, the piston (302) is positioned on the inner sides of the plurality of first inner friction plates (304) and the plurality of first outer friction plates (303), and the piston (302) is installed on the second shell (102) and can move between a braking position and a non-braking position;

the hub assembly (4) comprises a gear ring (401), a hub piece (402), planet wheels (405) and a planet carrier (406), the gear ring (401) is fixedly installed on the second shell (102) and presses the bearing plate (301), the hub piece (402) is installed on the planet carrier (406) and is in transmission connection with the planet carrier (406), the planet wheels (405) are respectively meshed with a half shaft (103) and are meshed with the inner teeth of the gear ring (401), and the planet carrier (406) and the planet wheels (405) jointly form an epicyclic gear train;

wherein when the service brake assembly (3) is in a braking state, the piston (302) is moved to a braking position such that the first plurality of inner friction plates (304) and the first outer friction plates (303) abut and press against the hub assembly (4).

2. The wet axle box integrated drive axle for the forklift according to claim 1, wherein the hub assembly (4) further comprises a bearing plate (301), the gear ring (401) presses the bearing plate (301) against the second housing (102), the bearing plate (301) and the piston (302) are respectively located at the inner side and the outer side of the first inner friction plate (304) and the first outer friction plate (303), and when the service brake assembly (3) is in the braking state, the piston (302) moves to the braking position so that the plurality of first inner friction plates (304) and the first outer friction plates (303) are abutted against and pressed against the bearing plate (301).

3. The wet axle box integrated drive axle for the forklift as claimed in claim 1, further comprising a lock nut (407) and two first tapered roller bearings (403), wherein the inner side wall of the gear ring (401) is further provided with a first annular protrusion, the two first tapered roller bearings (403) are sleeved on the hub member (402), the outer rings of the two first tapered roller bearings (403) are matched with the inner side hole of the gear ring (401), and the two first tapered roller bearings (403) are respectively located at the inner end and the outer end of the first annular protrusion and abut against the first annular protrusion; the lock nut (407) is screw-fitted to the hub member (402) and causes the carrier (406) to abut against the inner ring of the first tapered roller bearing (403) on the inner side, and locks the carrier (406) with the hub member (402).

4. The wet axle box integrated drive axle for the forklift as claimed in claim 3, further comprising a locking screw (408), wherein the locking screw (408) is fixedly mounted on the planet carrier (406) and used for limiting the rotation of the locking nut (407).

5. The wet axle box integrated drive axle for the forklift as recited in claim 1, wherein the carrier (406) further comprises a rotating portion extending into the planetary gear, and a needle bearing (410) is further provided, the needle bearing (410) is sleeved on the rotating portion and abuts against the inner side wall of the planetary gear;

still be equipped with circlip (409) and a gasket for the second shaft, still be equipped with a first annular groove on the rotation portion, circlip (409) is located first annular groove for the second shaft, the gasket is located between circlip (409) and planet wheel (405) for the second shaft, planet gear both ends face offsets with planet carrier (406) and gasket respectively.

6. The wet axle box integrated drive axle for the forklift as recited in claim 1, wherein the service brake assembly (3) further comprises a return spring seat (308), a return spring (309) and a return spring (309) screw which are positioned in the second housing (102), the return spring (309) enables the annular piston (302) to move 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 installed in the second mounting holes in an interference fit manner, the return spring (309) screw penetrates through the return spring seat (308) and is installed on the second housing (102), the return spring (309) is sleeved on the return spring (309) screw, one end of the return spring (309) abuts against the return spring seat (308), and the other end of the return spring (309) abuts against the return spring (309) screw;

the return spring (309) limits the stroke of the return spring seat (308) to be a first clearance through a screw, the annular piston (302) and the return spring seat (308) move together in an interference fit mode, and when the inner friction plate and the outer friction plate are in an unworn state, the displacement stroke between the braking position and the non-braking position of the annular piston (302) is not larger 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 fixed in an interference fit mode after relative displacement is generated, the return spring (309) is screwed to limit the stroke of the return spring seat (308) to be a first clearance, and therefore the displacement stroke between the braking position and the non-braking position of the annular piston (302) is the first clearance.

7. The wet axle box integrated drive axle for the forklift according to claim 1, wherein the input assembly (2) further comprises a parking brake assembly, the parking brake assembly comprises a parking brake mounting seat (211), a hand brake swing arm (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 forms a cavity (2114), the pressure plate (214) is smoothly and movably mounted on the parking brake mounting seat (211), the plurality of second outer friction plates (216) are mounted in the cavity (2114) and are circumferentially and axially movably matched, the plurality of second inner friction plates (215) are circumferentially and axially movably matched with the input shaft (206) of the input assembly (2) through splines, and the plurality of second inner friction plates (215) and the plurality of second outer friction plates (216) are alternately stacked with each other, the hand brake swing arm (212) is in transmission connection or fixed connection with a rotating shaft (213), 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 that the second inner friction plate (215) and the second outer friction plate (216) are pressed on the first shell (101).

8. The wet axle box integrated drive axle for the forklift as claimed in claim 7, further comprising a plurality of pins (217) uniformly distributed in a circumferential direction and a plurality of second springs (218) sleeved on the pins (217), wherein a plurality of second through holes uniformly distributed in a circumferential direction are formed in the second outer friction plates (216), the pins (217) pass through the second through holes in the second outer friction plates (216), the plurality of second springs (218) are sequentially distributed between two adjacent second outer friction plates (216), two ends of each second spring (218) respectively abut against two adjacent second outer friction plates (216), and further two adjacent second outer friction plates (216) are separated by the second springs (218) and the outer friction plate on one side abuts against the pressure plate (214).

9. The wet axle box integrated drive axle for a forklift according to claim 7, wherein the rotation shaft (213) is provided with a recessed portion (2131), and during rotation of the rotation shaft (213), the recessed portion (2131) is engaged with the pressure plate (214) to make the pressure plate (214) reciprocate in the left-right direction, thereby pressing the second inner friction plate (215) and the second outer friction plate (216) against the first housing (101).

10. The wet axle box integrated drive axle for the forklift according to claim 7, further comprising a shaft sleeve (219) and a first torsion spring (220), wherein the shaft sleeve (219) is sleeved on the rotating shaft (213) and located below the hand brake swing arm (212), the outer side wall of the shaft sleeve (219) abuts against the inner side wall of the first mounting hole (2112), the first torsion spring (220) is sleeved on the exterior of the parking brake mounting seat (211), one end of the first torsion spring (220) is clamped in the groove of the parking brake mounting seat (211), and the other end of the first torsion spring is inserted into the upper hole of the hand brake swing arm (212).