阅读说明：本技术 双桥悬架系统 (Double-axle suspension system ) 是由 马琳婧 陈琳 吴晓涛 王兆友 许长贺 关世伟 于 2021-10-08 设计创作，主要内容包括：本发明涉及一种双桥悬架系统,包括：车架,用于承载车身；第一悬架装置,包括第一驱动桥及第一承载机构,第一承载机构连接于车架,第一驱动桥连接于第一承载机构且位于车架背离车身的一侧；第二悬架装置,包括第二驱动桥、举升机构及第二承载机构,第二承载机构连接于车架,第二驱动桥连接于第二承载机构且位于车架背离车身的一侧；举升机构连接于车架和第二驱动桥,举升机构升降运动能带动第二驱动桥相对于车架升降运动。上述双桥悬架系统,通过调节第一悬架装置及第二悬架装置的工作状态,而调节车辆的承载工况；第一悬架装置及第二悬架装置能够传递驱动桥与车轮、车架之间的力和力矩；第二悬架装置可提升距离较大,可保证较好的整车通过性。(The invention relates to a double-axle suspension system, comprising: the frame is used for bearing the vehicle body; the first suspension device comprises a first drive axle and a first bearing mechanism, the first bearing mechanism is connected to the frame, and the first drive axle is connected to the first bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body; the second suspension device comprises a second drive axle, a lifting mechanism and a second bearing mechanism, the second bearing mechanism is connected to the frame, and the second drive axle is connected to the second bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body; the lifting mechanism is connected to the frame and the second drive axle, and the lifting mechanism can drive the second drive axle to move up and down relative to the frame through lifting movement. The double-axle suspension system adjusts the bearing working condition of the vehicle by adjusting the working states of the first suspension device and the second suspension device; the first suspension device and the second suspension device can transmit force and moment among the drive axle, the wheels and the frame; the second suspension device can be lifted a larger distance, and can ensure better passing performance of the whole vehicle.)

1. A dual axle suspension system comprising:

the frame is used for bearing the vehicle body;

the first suspension device is connected to one side of the frame, which is far away from the vehicle body; the first suspension device comprises a first drive axle and a first bearing mechanism, the first bearing mechanism is connected to the frame, and the first drive axle is connected to the first bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body;

the second suspension device is connected to one side of the frame, which is far away from the vehicle body; the second suspension device comprises a second drive axle, a lifting mechanism and a second bearing mechanism, the second bearing mechanism is connected to the frame, and the second drive axle is connected to the second bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body; the lifting mechanism is connected to the frame and the second drive axle, and the lifting mechanism can drive the second drive axle to move up and down relative to the frame through lifting movement.

2. The dual axle suspension system of claim 1 wherein said first load bearing mechanism includes a first resilient member movably coupled to said frame and a first fastener clamped about a periphery of said first resilient member and fixedly coupled to said first drive axle.

3. The dual axle suspension system of claim 2 wherein said first resilient assembly includes a primary resilient member and a secondary resilient member, said primary and secondary resilient members being in a stacked configuration and secured by said first fastener, both ends of said primary resilient member being movably connected to said frame.

4. The dual-axle suspension system according to claim 3, wherein the first bearing mechanism further comprises an adapter and two fixing seats, the two fixing seats are disposed on the frame at intervals, the adapter is movably connected to one of the fixing seats, one end of the main elastic member is movably connected to the other fixing seat, and the other end of the main elastic member is movably connected to the adapter.

5. The dual axle suspension system of claim 3 wherein said primary spring comprises a plurality of stacked primary clips and/or said secondary spring comprises a plurality of stacked secondary clips.

6. The dual axle suspension system of claim 1 wherein said second load bearing mechanism includes a second resilient assembly movably connected to said frame and a second fastener secured to said second resilient assembly and fixedly connected to said second drive axle.

7. The dual axle suspension system of claim 6 wherein said second resilient assembly includes a load bearing springboard and a load bearing air spring, one end of said load bearing springboard is movably connected to said vehicle frame, the other end of said load bearing springboard is fixedly connected to the bottom of said load bearing air spring, and the top of said load bearing air spring is fixedly connected to said vehicle frame.

8. The dual axle suspension system of claim 7 wherein said lift mechanism includes a lift spring assembly mounted to said frame and a third fastener secured to said lift spring assembly and connected to said secondary drive axle.

9. The dual axle suspension system of claim 8, wherein the resilient lifting assembly comprises a lifting air spring, a cover plate and a connecting frame, wherein the lifting air spring is fixedly connected to the cover plate and the connecting frame at two sides thereof, the third fastening member is fixed to the cover plate, and the connecting frame is fixed to the frame.

10. The dual axle suspension system of claim 9, wherein the second suspension device further comprises a controller and a control valve electrically connected to each other, the control valve has two air flow passages respectively connected to the load air spring and the lift air spring, and the controller controls the on/off of the air flow passages to control the on/off of the air paths of the load air spring and the lift air spring.

Technical Field

The invention relates to the technical field of automobile suspensions, in particular to a double-axle suspension system.

Background

According to the condition that the profit space of the freight market is gradually compressed, users have demands on vehicles with low cost, low oil consumption and low loss, and the liftable suspension scheme is gradually applied. The bridge can be lifted to the ground when the bridge is fully loaded, so that the load requirement is realized; the lifting bridge can be lifted during no-load or light load, the tire wear is reduced, the oil consumption is reduced, and the economic benefit is improved.

The existing liftable suspension system is provided with a trailer suspension frame with a lifting structure, the structure is heavy in weight, the no-load lifting distance is limited, and the trafficability of the whole vehicle is poor; in addition, the full air spring air suspension frame is provided with a lifting structure, so that no-load lifting can be realized, but the cost is higher, and the market acceptance is poor.

Disclosure of Invention

Based on this, it is necessary to provide a light-weight, low-cost, no-load or half-load liftable dual-axle suspension system, which not only meets the requirements of users on low-cost and low-oil-consumption vehicles, but also ensures better vehicle trafficability.

A dual axle suspension system comprising:

the frame is used for bearing the vehicle body;

the first suspension device is connected to one side of the frame, which is far away from the vehicle body; the first suspension device comprises a first drive axle and a first bearing mechanism, the first bearing mechanism is connected to the frame, and the first drive axle is connected to the first bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body;

the second suspension device is connected to one side of the frame, which is far away from the vehicle body; the second suspension device comprises a second drive axle, a lifting mechanism and a second bearing mechanism, the second bearing mechanism is connected to the frame, and the second drive axle is connected to the second bearing mechanism and is positioned on one side of the frame, which is far away from the vehicle body; the lifting mechanism is connected to the frame and the second drive axle, and the lifting mechanism can drive the second drive axle to move up and down relative to the frame through lifting movement.

According to the double-axle suspension system, the first suspension device has a bearing effect, the second suspension device has a bearing and lifting effect, and the bearing working condition of the vehicle is adjusted by adjusting the working states of the first suspension device and the second suspension device so as to meet the actual use requirement of the vehicle, so that the energy utilization rate of the vehicle is improved; the first suspension device and the second suspension device can transfer force and moment among the drive axle, the wheels and the frame, play a role in bearing, can better buffer load impact of the wheels on the frame, and are favorable for ensuring stable driving; the second suspension device can be lifted a larger distance, and can ensure better passing performance of the whole vehicle.

In one embodiment, the first bearing mechanism includes a first elastic component and a first fastener, the first elastic component is movably connected to the frame, and the first fastener is clamped on the periphery of the first elastic component and is fixedly connected with the first drive axle.

In one embodiment, the first elastic assembly includes a main elastic member and an auxiliary elastic member, the main elastic member and the auxiliary elastic member are in a laminated structure and fixed by the first fastening member, and two ends of the main elastic member are movably connected to the frame.

In one embodiment, the first bearing mechanism further includes an adaptor and two fixing seats, the two fixing seats are disposed on the frame at intervals, the adaptor is movably connected to one of the fixing seats, one end of the main elastic member is movably connected to the other fixing seat, and the other end of the main elastic member is movably connected to the adaptor.

In one embodiment, the primary elastic member includes a plurality of stacked primary elastic pieces, and/or the secondary elastic member includes a plurality of stacked secondary elastic pieces.

In one embodiment, the second bearing mechanism includes a second elastic component and a second fastening component, the second elastic component is movably connected to the frame, and the second fastening component is fixed to the second elastic component and is fixedly connected to the second drive axle.

In one embodiment, the second elastic assembly includes a bearing elastic plate and a bearing air spring, one end of the bearing elastic plate is movably connected to the frame, the other end of the bearing elastic plate is fixedly connected to the bottom of the bearing air spring, and the top of the bearing air spring is fixedly connected to the frame.

In one embodiment, the lifting mechanism includes a lifting elastic component and a third fastener, the lifting elastic component is mounted on the frame, and the third fastener is fixed on the lifting elastic component and connected with the second drive axle.

In one embodiment, the lifting elastic assembly includes a lifting air spring, a cover plate and a connecting frame, two sides of the lifting air spring are respectively and fixedly connected with the cover plate and the connecting frame, the third fastening member is fixed to the cover plate, and the connecting frame is fixed to the frame.

In one embodiment, the second suspension device further includes a controller and a control valve electrically connected to each other, the control valve has two air flow passages respectively connected to the load bearing air spring and the lifting air spring, and the controller controls the opening and closing of the air flow passages to control the opening and closing of the air paths of the load bearing air spring and the lifting air spring.

Drawings

FIG. 1 is a schematic view of a first angle of a dual axle suspension system in accordance with an embodiment;

FIG. 2 is a schematic view of a second angle of the dual axle suspension system of FIG. 1;

FIG. 3 is a schematic view of a lift mechanism in the dual axle suspension system of FIG. 1;

fig. 4 is a schematic diagram of pneumatic control of a control valve in the dual axle suspension system shown in fig. 1.

Reference numerals:

100. a frame; 200. a first suspension device; 210. a first drive axle; 220. a first bearing mechanism; 221. a first elastic member; 221a, a main elastic member; 221b, a secondary elastic member; 222. a first fastener; 222a and a first clamping part; 222b, a first locking part; 223. an adapter; 224. a fixed seat; 225. a first limit piece; 226. a second limiting member; 300. a second suspension device; 310. a second drive axle; 320. a second bearing mechanism; 321. a second elastic member; 322. a second fastener; 322a, a second clamping part; 322b, a second locking portion; 323. a bearing spring plate; 324. a load bearing air spring; 330. a lifting mechanism; 331. lifting the elastic component; 332. a third fastener; 332a, a third engaging portion; 332b, a third locking portion; 333. lifting the air spring; 334. a cover plate; 335. a connecting frame; 336. a third limiting member; 340. a control valve; 341. a first solenoid valve; 342. a second solenoid valve; 343. a pressure limiting valve.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the 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 at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, a dual axle suspension system in one embodiment includes a frame 100, a first suspension device 200, and a second suspension device 300. The frame 100 is used for bearing a vehicle body, the first suspension device 200 is connected to a side 101 of the frame 100 departing from the vehicle body and has a bearing effect, and the second suspension device 300 is connected to the side 101 of the frame 100 departing from the vehicle body and has a bearing effect and a lifting effect.

With reference to fig. 1, the first suspension device 200 includes a first drive axle 210 and a first carrying mechanism 220, the first carrying mechanism 220 is connected to the frame 100, and the first drive axle 210 is connected to the first carrying mechanism 220 and located on a side 101 of the frame 100 away from the vehicle body. The second suspension device 300 includes a second driving axle 310, a second carrying mechanism 320 and a lifting mechanism 330, the second carrying mechanism 320 is connected to the frame 100, and the second driving axle 310 is connected to the second carrying mechanism 320 and located on a side 101 of the frame 100 facing away from the vehicle body. The lifting mechanism 330 is connected to the second driving axle 310, and the lifting mechanism 330 can drive the second driving axle 310 to move up and down relative to the frame 100 by the lifting movement.

It should be noted here that the side 101 of the frame 100 facing away from the vehicle body refers to the bottom side of the frame 100. The first driving axle 210 and the second driving axle 310 are respectively connected to wheels, and the lifting mechanism 330 can drive the second driving axle 310 and the wheels to synchronously lift and lower along the X direction shown in fig. 1.

When the vehicle is in a full-load working condition, the first suspension device 200 and the second suspension device 300 both have a bearing effect, and the second drive axle 310 falls to the ground, so that the requirement of higher bearing load can be met; when the vehicle is in a non-full load condition (e.g., no load or half load), the first suspension apparatus 200 performs a load-bearing function, the second suspension apparatus 300 performs a lifting function, and the lifting mechanism 330 drives the second drive axle 310 and the wheels to lift synchronously, so as to meet a general load-bearing requirement.

Through the arrangement, the bearing working condition of the vehicle is adjusted by adjusting the working states of the first suspension device 200 and the second suspension device 300 so as to meet the actual use requirement of the vehicle, thereby improving the energy utilization rate of the vehicle; the first suspension device 200 and the second suspension device 300 can transmit force and moment between a drive axle and wheels and between the drive axle and the frame 100, play a role in bearing, can better buffer load impact of the wheels on the frame 100, and are beneficial to ensuring stable driving; the second suspension device 300 can be lifted a long distance, and can ensure good passing performance of the whole vehicle. In the embodiment shown in fig. 1, the first supporting mechanism 220 includes a first elastic component 221 and a first fastening member 222, the first elastic component 221 is movably connected to the frame 100, and the first fastening member 222 is clamped on the outer periphery of the first elastic component 221 and is fixedly connected to the first axle 210.

Specifically, the first fastening member 222 includes a first clamping portion 222a and a first locking portion 222b, the first clamping portion 222a is open at one end, and the first locking portion 222b is movably connected to the opening of the first clamping portion 222 a. The first clamping portion 222a is clamped at the periphery of the first elastic component 221 and sleeved outside the first drive axle 210, and the first locking portion 222b is locked at the opening of the first clamping portion 222a so that the first drive axle 210 is limited between the first locking portion 222b and the first elastic component 221.

Through the above arrangement, the first drive axle 210 is connected to the first elastic component 221 through the first fastener 222, and the first elastic component 221 can move relative to the frame 100, so that the impact force transmitted to the frame 100 or the vehicle body due to the uneven road surface can be buffered, and the driving stability of the vehicle can be ensured.

In a particular embodiment, the first fastener 222 is a U-bolt.

As shown in fig. 1, the first elastic assembly 221 includes a main elastic member 221a and an auxiliary elastic member 221b, the main elastic member 221a and the auxiliary elastic member 221b are stacked and fixed by a first fastening member 222, and both ends of the main elastic member 221a are movably connected to the frame 100.

Specifically, the main elastic member 221a includes a plurality of main resilient pieces stacked (i.e., stacked in the X direction shown in fig. 1), and/or the sub elastic member 221b includes a plurality of sub resilient pieces stacked (i.e., stacked in the X direction shown in fig. 1). With this arrangement, the load-bearing performance and the cushioning performance of the first elastic member 221 are enhanced.

As shown in fig. 1, in the embodiment, the main elastic pieces have equal widths, and the lengths thereof are gradually reduced from top to bottom along the vertical direction (i.e., the X direction shown in fig. 1), and the auxiliary elastic pieces have equal widths, and the lengths thereof are gradually reduced from top to bottom along the axial direction, so as to meet the requirements of load-bearing and buffering performances.

In the embodiment, the primary elastic member 221a and the secondary elastic member 221b are each a leaf spring.

Referring to fig. 1, the first supporting mechanism 220 further includes an adapter 223 and two fixing bases 224, the two fixing bases 224 are disposed on the frame 100 at intervals, the adapter 223 is movably connected to one fixing base 224, one end of the main elastic component 221a is movably connected to the other fixing base 224, and the other end of the main elastic component 221a is movably connected to the adapter 223.

It can be understood that one end of the main elastic member 221a is movably connected to a fixing seat 224, and the other end of the main elastic member 221a is movably connected to another fixing seat 224 through an adapter 223, which is equivalent to that a swing arm is added to the other end of the main elastic member 221a, so that the movable range of the main elastic member 221a relative to the frame 100 is expanded.

In one embodiment, the adapter 223 may be a lifting ring. The rolling ears at the two ends of the main elastic element 221a are respectively and rotatably connected with the fixed seat 224 and the hanging ring through pin shafts. In other embodiments, the adaptor 223 may also be a telescopic connecting arm, so as to adjust the length of the connecting arm and adjust the rotation amplitude. The rolling ears at the two ends of the main elastic element 221a can also be respectively rotatably connected with the fixed seat 224 and the hanging ring through spherical hinges.

Further, referring to fig. 1, the first supporting mechanism 220 further includes a first limiting member 225, and the first limiting member 225 is fixed to the frame 100 and is used for limiting and supporting the first elastic assembly 221.

It can be understood that, in this embodiment, since the main elastic element 221a can rotate around the pin shaft relative to the frame 100 and the auxiliary elastic element 221b can rotate synchronously with the main elastic element 221a, the first limiting element 225 is required to limit the rotation range so as to prevent the auxiliary elastic element 221b from being over-moved and impacting and damaging the vehicle body.

When the secondary elastic member 221b is not in contact with the first limiting member 225, only the primary elastic member 221a plays a bearing role; when the secondary elastic member 221b contacts the first stopper 225, the secondary elastic member 221b and the primary elastic member 221a simultaneously perform a load-bearing function.

In one embodiment, referring to fig. 1, the number of the first limiting members 225 is two, and two first limiting members 225 are disposed above the secondary elastic member at intervals. In other embodiments, the number of the first limiting members 225 may also be other values, and is not limited herein.

Referring to fig. 1, the first supporting mechanism 220 further includes a second limiting member 226, and the second limiting member 226 is fixed to a side 101 of the frame 100 away from the vehicle body and is used for limiting the position of the first driving axle 210.

It will be appreciated that first drive axle 210 is movable relative to frame 100, as first drive axle 210 is coupled to frame 100. The second limiting member 226 is arranged to limit the range of motion of the first drive axle 210, so that the first drive axle 210 is prevented from directly impacting the side 101 of the frame 100 away from the vehicle body when moving.

Referring to fig. 1, the second supporting mechanism 320 of the second suspension apparatus 300 includes a second elastic component 321 and a second fastening component 322, the second elastic component 321 is movably connected to the frame 100, and the second fastening component 322 is fixed to the second elastic component 321 and fixedly connected to the second drive axle 310.

Specifically, as shown in fig. 1, the second fastening member 322 includes a second clamping portion 322a and a second locking portion 322b, the second clamping portion 322a has an opening at one end, and the second locking portion 322b is fixedly connected to the opening of the second clamping portion 322 a. The second engaging portion 322a is sleeved outside the second driving axle 310, and the first locking portion 322b is locked at the opening of the second engaging portion 322a and is fixedly connected to the second elastic component 321.

Through the arrangement, the second drive axle 310 is connected to the second elastic component 321, and the second elastic component 321 can move relative to the vehicle frame 100, and can transmit the force and moment acting between the second drive axle 310 and the vehicle frame 100 (or the vehicle body), so as to play a bearing role, buffer the impact force transmitted to the vehicle frame 100 or the vehicle body due to uneven road surfaces, and ensure the driving stability of the vehicle.

In a specific embodiment, the second fastener 322 is a U-bolt.

As shown in fig. 1 and 2, the second elastic assembly 321 includes a bearing elastic plate 323 and a bearing air spring 324, one end of the bearing elastic plate 323 is movably connected to the frame 100, the other end of the bearing elastic plate 323 is fixedly connected to the bottom of the bearing air spring 324, and the top of the bearing air spring 324 is fixedly connected to the frame 100.

In a specific embodiment, as shown in fig. 2, the bearing elastic plate 323 is a single-piece structure, and a distance between one end of the bearing elastic plate 323 and the center of the second drive axle 310 is greater than a distance between the middle of the bearing air spring 324 and the center of the second drive axle 310, so that a force applied to one end of the bearing elastic plate 323 is smaller than a force applied to the bearing air spring 324, and the second bearing mechanism 320 can meet a bearing requirement and reduce weight.

In a specific embodiment, the front rolling lug of the bearing spring plate 323 is rotatably connected to the frame 100 through a pin, the rear end of the bearing spring plate 323 is fixedly connected to the bottom of the bearing air spring 324, and the front rolling lug and the pin are connected by a large bushing structure.

Further, as shown in fig. 1 and 2, the bearing elastic plate 323 has an axisymmetric structure, and the other end of the bearing elastic plate 323 is coaxially disposed with the middle of the bearing air spring 324, so as to facilitate uniform stress on the bearing elastic plate 323 and the bearing air spring 324.

In particular embodiments, the load air spring 324 may be any one of a bladder air spring and a diaphragm air spring.

Referring to fig. 2 and 3, the lifting mechanism 330 of the second suspension apparatus 300 includes a lifting elastic element 331 and a third fastener 332, wherein the lifting elastic element 331 is mounted on the frame 100, and the third fastener 332 is fixed to the lifting elastic element 331 and connected to the second drive axle 310.

Specifically, as shown in fig. 3, the third fastening member 332 includes a third engaging portion 332a and a third locking portion 332b, the third engaging portion 332a has an open end, and the third locking portion 332b is fixedly connected to the opening of the second engaging portion 322 a. The third engaging portion 332a is sleeved outside the second driving axle 310, and the second locking portion 322b is locked at the opening of the second engaging portion 322a and is fixedly connected to the lifting elastic element 331.

In a particular embodiment, the third fastener 332 is a U-bolt.

Referring to fig. 3, the lifting resilient assembly 331 includes a lifting air spring 333, a cover 334 and a connecting frame 335, wherein the two sides of the lifting air spring 333 are respectively fixed to the cover 334 and the connecting frame 335, the third fastening member 332 is fixed to the cover 334, and the connecting frame 335 is fixed to the frame 100.

In particular embodiments, the lifting air spring 333 may be any one of a bladder air spring and a diaphragm air spring.

Through the above arrangement, the lifting air spring 333 is controlled to drive the second drive axle 310 and the wheels to synchronously lift.

For example, when the vehicle is in a full load condition, the second suspension device 300 performs a load bearing function, the load bearing air spring 324 of the second suspension device 300 is inflated, the lifting air spring 333 of the second suspension device 300 is deflated, and the second drive axle 310 descends under the action of gravity and lands; when the vehicle is in a non-full-load condition (for example, no-load or half-load), the second suspension device 300 is in a lifting state, the bearing air spring 324 of the second suspension device 300 is deflated, and the lifting air spring 333 of the second suspension device 300 is inflated to drive the second drive axle 310 and the wheels to lift. .

In a specific embodiment, as shown in fig. 3, the lifting mechanism 330 further includes a third limiting member 336, the third limiting member 336 is fixedly disposed on the side 101 of the frame 100 away from the vehicle body and is used for limiting the second driving axle 310, so as to prevent the second driving axle 310 from impacting the side 101 of the frame 100 away from the vehicle body and damaging the frame 100 when the second driving axle 310 moves up and down, and meanwhile, when the second driving axle 310 is lifted to the limit, the height of the load bearing air spring 324 is greater than the compression limit thereof, so as to improve the service life of the load bearing air spring 324.

In the specific embodiment, as shown in fig. 1 and 3, the frame 100 has an axisymmetrical structure, one lifting air spring 333 is disposed in the middle of the frame 100, two load bearing air springs 324 are disposed, and the two load bearing air springs 324 are symmetrically disposed on the bottom side 101 of the longitudinal beam of the frame 100, so as to balance the stress of the frame 100. In other embodiments, the lifting air spring 333 and the loading air spring 324 may have other values, and are not limited herein.

Referring to fig. 4, the second suspension apparatus 300 further includes a controller (not shown) and a control valve 340 electrically connected to each other, wherein the control valve 340 has two air flow passages, and the two air flow passages are respectively connected to the load air spring 324 and the lift air spring 333. The opening and closing of the air flow channel are controlled by the controller, so that the air paths of the bearing air spring 324 and the lifting air spring 333 are controlled to be on and off.

Specifically, with continued reference to fig. 4, the control valve 340 includes a first solenoid valve 341 and a second solenoid valve 342, the first solenoid valve 341 has a first air flow passage connected to the load air spring 324, and the second solenoid valve 342 has a second air flow passage connected to the lift air spring 333.

When the first solenoid valve 341 and the second solenoid valve 342 are both de-energized, the first air flow channel is communicated, and the second air flow channel is closed; when the first solenoid valve 341 and the second solenoid valve 342 are energized, the first air flow passage is closed, and the second air flow passage is communicated.

For example, when the vehicle is in a full load condition, the second suspension device 300 is in a load state, the first solenoid valve 341 and the second solenoid valve 342 are both de-energized, and at this time, the load air spring 324 can be inflated and the lift air spring 333 deflated; when the vehicle is in a non-full load condition (e.g., no load or half load), the second suspension apparatus 300 is in a lifted state, the first solenoid valve 341 and the second solenoid valve 342 are both energized, and the lifting air spring 333 is inflated and the loading air spring 324 is deflated.

With the arrangement, no matter the secondary suspension device 300 is in the loading state or the lifting state, when the vehicle is powered off and the power is off, the loading air spring 324 can be inflated to drive the secondary drive axle 310 to be in contact with the ground, so that the situation that the loading air spring 324 and the lifting air spring 333 are simultaneously deflated due to the accidental power off of the vehicle, and the secondary drive axle 310 is disabled is avoided.

Further, as shown in fig. 4, because the working air pressures of the lifting air spring 333 and the load bearing air spring 324 are different, a pressure limiting valve 343 is additionally arranged in front of the first air flow channel and the second air flow channel, so as to ensure that the working air pressures of the lifting air spring 333 and the load bearing air spring 324 are in a normal range.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.