阅读说明：本技术 一种车桥壳的密封检验装置 (Sealing inspection device for axle housing ) 是由 高克亮 王传飞 于 2020-04-03 设计创作，主要内容包括：本发明公开了一种车桥壳的密封检验装置,涉及车桥领域,包括底座；传送链、固定于传送链的若干传送杆以及固定于车桥壳外侧表面的固定块,传送杆的底部设有勾状物,用于勾住固定块；第一横杆以及固定于第一横杆上的若干第一喷嘴,第一喷嘴通过导管与装有酚酞试液的储液腔连通,储液腔位于第一喷嘴的上方；通气部以及与通气部相匹配的导气端头,导气端头与车桥壳的内部连通；当车桥壳移动至第一横杆下方时,通气部与导气端头连通,并通过导气端头向车桥壳内部通入碱性气体；然后第一喷嘴打开,酚酞试液从第一喷嘴喷至车桥壳外表面,如果车桥壳的表面的酚酞试液有红色出现,则说明在车桥壳出现红色的地方,有漏气的现象,从而准确标记漏气位置。(The invention discloses a sealing inspection device for an axle housing, which relates to the field of axles and comprises a base; the conveying chain, a plurality of conveying rods fixed on the conveying chain and a fixing block fixed on the outer side surface of the axle housing, wherein hooks are arranged at the bottom of the conveying rods and used for hooking the fixing block; the device comprises a first cross rod and a plurality of first nozzles fixed on the first cross rod, wherein the first nozzles are communicated with a liquid storage cavity filled with phenolphthalein test solution through a guide pipe, and the liquid storage cavity is positioned above the first nozzles; the air guide end is communicated with the interior of the axle housing; when the axle housing moves to the position below the first cross rod, the air vent part is communicated with the air guide end, and alkaline gas is introduced into the axle housing through the air guide end; then the first nozzle is opened, the phenolphthalein test solution is sprayed to the outer surface of the axle housing from the first nozzle, if the phenolphthalein test solution on the surface of the axle housing appears red, the phenomenon of air leakage exists at the place where the red phenolphthalein test solution appears on the axle housing, and therefore the air leakage position is accurately marked.)

1. The utility model provides a sealed verifying attachment of axle housing which characterized in that: comprises that

A base (1);

the conveying device comprises a conveying chain (2), a plurality of conveying rods (3) fixed on the conveying chain (2) and at least two fixing blocks (6) fixed on the outer side surface of a vehicle axle housing, wherein hooks are arranged at the bottom of the conveying rods (3) and used for hooking the fixing blocks (6);

the device comprises at least one first cross rod (4) fixed on the base (1) through a fixing piece and a plurality of first nozzles (5) fixed on the first cross rod (4), wherein the first nozzles (5) are communicated with a liquid storage cavity filled with phenolphthalein test solution through a guide pipe, the liquid storage cavity is positioned above the first nozzles (5), and when the axle housing moves to the position below the first cross rod (4), the first nozzles (5) spray the phenolphthalein test solution;

the air guide end is fixed on the outer surface of the axle housing and communicated with the interior of the axle housing;

when the axle housing moves to the position below the first cross rod (4) through the conveying chain (2), the air vent part is communicated with the air guide end head, and alkaline gas is introduced into the axle housing through the air guide end head; and then the first nozzle (5) is opened, and the phenolphthalein test solution is sprayed to the outer surface of the axle housing from the first nozzle (5).

2. The axle housing seal inspection device of claim 1 wherein: the number of the first cross rods (4) is two, and the first cross rods are symmetrically arranged; when the axle housing moves to base (1) top, the axle housing is located the below of two first horizontal poles (4) intermediate positions.

3. The axle housing seal inspection device of claim 1 wherein: the liquid storage device is characterized by further comprising at least one second cross rod (13) and a plurality of second nozzles (14), wherein the second cross rod (13) is fixed on the base (1) through a fixing piece, and the second nozzles (14) are communicated with the liquid storage cavity through a guide pipe; when the axle housing moves to first horizontal pole (4) below, second horizontal pole (13) are located the below of axle housing, just second nozzle (14) are towards the side surface of axle housing below.

4. A seal inspection device for an axle housing according to claim 3, wherein: comprises a separation plate (10) fixed on a base (1), and a detection groove (12) is arranged in the separation plate; the detection groove (12) penetrates through the left side surface, the right side surface and the upper end surface of the isolation plate (10), and an outlet (11) is formed in the bottom of the detection groove; the first cross rod (4) and the second cross rod (13) are both positioned in the detection groove (12).

5. The axle housing seal inspection device of claim 4 wherein: the ventilation part comprises a first air cylinder (7) fixed on the base (1) through a connecting block, an air tank (8) fixed on the base (1), an air pump (9) with an air inlet communicated with an outlet of the air tank (8), a ventilation rod (16) with a ventilation cavity (21) arranged inside and an air pipe (19); one end of the ventilation rod (16) is connected with an output shaft of the first cylinder (7), the other end of the ventilation rod penetrates through a through hole (24) formed in the side face of the isolation plate (10) and extends into the detection groove (12), the opening of the ventilation cavity (21) faces the end face, located in the detection groove (12), of the ventilation rod (16), the diameter of the air guide end is equal to that of the ventilation cavity (21), when the axle housing moves to the detection groove (12), the air guide end faces the opening of the ventilation cavity (21), and the first cylinder (7) drives the ventilation rod (16) to enable the air guide end to be inserted into the ventilation cavity (21); alkaline gas is filled in the gas tank (8), and the outlet of the gas pump (9) is communicated with the ventilation cavity (21) through the gas pipe (19).

6. The axle housing seal inspection device of claim 5 wherein: the device comprises an electromagnetic valve (20), wherein the electromagnetic valve (20) is fixed on a ventilation rod (16) and used for controlling the on-off of a ventilation cavity (21), and the fixing position of the electromagnetic valve (20) is positioned between the communication position of an air pipe (19) and the ventilation cavity (21) and the opening of the ventilation cavity (21).

7. The axle housing seal inspection device of claim 5 wherein: the air cylinder structure is characterized by comprising an adjusting plate (15) with one side fixed to a first air cylinder (7), a second air cylinder (17), an upper partition plate (22), a lower partition plate (25) and a spring (27), wherein an upper sliding groove (23) is formed in the upper side wall of a through hole (24), a lower sliding groove (26) is formed in the lower side wall of the through hole (24), the upper partition plate (22) is in sliding connection with the upper sliding groove (23), the lower partition plate (25) is in sliding connection with the lower sliding groove (26), the lower end of the lower partition plate (25) is fixedly connected with one end of the spring (27), the other end of the spring (27) is fixedly connected with the bottom of the lower sliding groove (26), and the width of the upper partition plate (22) and the width of the lower partition plate (25) are equal to the; the second cylinder (17) is fixed above the upper chute (23), and an output shaft of the second cylinder is fixedly connected with the upper end part of the upper clapboard (22); the ventilation rod (16) is positioned between the upper partition plate (22) and the lower partition plate (25), the lower end face of the upper partition plate (22) and the upper end face of the lower partition plate (25) are respectively provided with a semicircular groove matched with the side surface of the ventilation rod (16), the ventilation rod (16) penetrates through the semicircular grooves, and when the second air cylinder (17) is started, the ventilation rod (16) moves in the vertical direction; the side surface of the adjusting plate (15) facing the ventilation rod (16) is provided with an adjusting groove (18), and the end part of the ventilation rod (16) is connected with the adjusting groove (18) in a sliding manner.

8. The axle housing seal inspection device of claim 1 wherein: the device comprises a motor (28) fixed at the bottom of a detection groove (12), a threaded rod (29) connected with an output shaft of the motor (28) through a coupler, a support frame (30), a pressure sensor (31) and a stabilizer bar (32), wherein the support frame (30) comprises a transverse plate and a vertical plate, the vertical plate is arranged at two ends of the transverse plate, the threaded rod (29) is in threaded connection with the middle position of the transverse plate, one end of the stabilizer bar (32) is fixed at the bottom of the detection groove (12), and the other end of the stabilizer bar (32) penetrates through the transverse plate and is in sliding connection with the transverse plate; when axle housing moved to detecting in groove (12), support frame (30) were located the below of axle housing, and two risers were located the both sides of axle housing, the top of riser was equipped with pressure sensor (31), pressure sensor (31) and motor (28) electric connection.

Technical Field

The invention relates to the field of axles, in particular to a sealing inspection device for an axle housing.

Background

The automobile axle (also called as axle) is connected with the frame (or the bearing type automobile body) through the suspension, and wheels are arranged at the two ends of the automobile axle. The axle housing of the electric automobile is an important part on the automobile, has high requirement on air tightness, and requires no air leakage, so that the welding quality is high, and the welding seam cannot be subjected to cold welding and air leakage.

The applicant found that: when the method of inflating the interior of the axle housing and then putting the axle housing into water is adopted to detect the sealing performance of the axle housing, when air leaks, air bubbles can be generated in the water, but the air leakage position cannot be accurately marked.

Disclosure of Invention

In view of this, the present invention provides a sealing inspection device for an axle housing, so as to solve the technical problem that when the sealing performance of the axle housing is detected by inflating the interior of the axle housing and then placing the axle housing into water, bubbles are generated in the water during air leakage, but the air leakage position cannot be accurately marked.

Based on the above purpose, the invention provides a sealing inspection device for an axle housing, which comprises

A base;

the conveying device comprises a conveying chain, a plurality of conveying rods fixed on the conveying chain and at least two fixing blocks fixed on the outer side surface of the axle housing, wherein hooks are arranged at the bottom of the conveying rods and used for hooking the fixing blocks;

the device comprises at least one first cross rod fixed on a base through a fixing piece and a plurality of first nozzles fixed on the first cross rod, wherein the first nozzles are communicated with a liquid storage cavity filled with phenolphthalein test solution through a guide pipe, the liquid storage cavity is positioned above the first nozzles, and when an axle housing moves to the position below the first cross rod, the first nozzles spray the phenolphthalein test solution;

the air guide end is fixed on the outer surface of the axle housing and communicated with the interior of the axle housing;

when the axle housing moves to the position below the first cross rod through the conveying chain, the air vent part is communicated with the air guide end, and alkaline gas is introduced into the axle housing through the air guide end; and then the first nozzle is opened, and the phenolphthalein test solution is sprayed to the outer surface of the axle housing from the first nozzle.

Furthermore, two first cross rods are arranged and are symmetrically arranged; when the axle housing moves to the base top, the axle housing is located the below of two first horizontal pole intermediate positions.

The liquid storage device further comprises at least one second cross rod and a plurality of second nozzles, wherein the second cross rod is fixed on the base through a fixing piece, and the second nozzles are communicated with the liquid storage cavity through a guide pipe; when the axle housing moves to first horizontal pole below, the second horizontal pole is located the below of axle housing, just the second nozzle is towards the side surface of axle housing below.

Further, the device comprises a separation plate fixed on the base, wherein a detection groove is arranged in the separation plate; the detection groove penetrates through the left side surface, the right side surface and the upper end surface of the isolation plate, and an outlet is formed in the bottom of the detection groove; the first cross rod and the second cross rod are both located in the detection groove.

Further, the ventilation part comprises a first air cylinder fixed on the base through a connecting block, an air tank fixed on the base, an air pump with an air inlet communicated with an outlet of the air tank, a ventilation rod with a ventilation cavity arranged inside and an air pipe; one end of the ventilation rod is connected with an output shaft of the first cylinder, the other end of the ventilation rod penetrates through a through hole formed in the side face of the isolation plate and extends into the detection groove, an opening of the ventilation cavity faces the end face, located in the detection groove, of the ventilation rod, the diameter of the air guide end is equal to that of the ventilation cavity, when the axle housing moves to the detection groove, the air guide end faces the opening of the ventilation cavity, and the first cylinder drives the ventilation rod to enable the air guide end to be inserted into the ventilation cavity; alkaline gas is filled in the gas tank, and the outlet of the gas pump is communicated with the ventilation cavity through the gas pipe.

Furthermore, the device comprises an electromagnetic valve, wherein the electromagnetic valve is fixed on the ventilation rod and used for controlling the on-off of the ventilation cavity, and the fixed position of the electromagnetic valve is positioned between the communication position of the air pipe and the ventilation cavity and the opening of the ventilation cavity.

The device comprises a regulating plate, a second cylinder, an upper partition plate, a lower partition plate and a spring, wherein one side of the regulating plate is fixed on the first cylinder, the upper side wall of the through hole is provided with an upper chute, the lower side wall of the through hole is provided with a lower chute, the upper partition plate is in sliding connection with the upper chute, the lower partition plate is in sliding connection with the lower chute, the lower end of the lower partition plate is fixedly connected with one end of the spring, the other end of the spring is fixedly connected with the bottom of the lower chute, and the width of the upper partition plate and the width of the lower partition plate are equal to the width of the through; the second cylinder is fixed above the upper chute, and an output shaft of the second cylinder is fixedly connected with the upper end part of the upper clapboard; the ventilation rod is positioned between the upper partition plate and the lower partition plate, semicircular grooves matched with the side surfaces of the ventilation rod are formed in the lower end surface of the upper partition plate and the upper end surface of the lower partition plate, the ventilation rod penetrates through the semicircular grooves, and when the second cylinder is started, the ventilation rod moves in the vertical direction; the side of regulating plate towards the ventilation pole is equipped with the adjustment tank, the tip and the adjustment tank sliding connection of ventilation pole.

The device comprises a motor fixed at the bottom of a detection groove, a threaded rod connected with an output shaft of the motor through a coupler, a support frame, a pressure sensor and a stabilizer bar, wherein the support frame comprises a transverse plate and a vertical plate; when axle housing moved to detecting the inslot, the support frame was located axle housing's below, and two risers were located axle housing's both sides, the top of riser is equipped with pressure sensor, pressure sensor and motor electric connection.

The invention has the beneficial effects that: by adopting the sealing inspection device for the axle housing, the axle housing is driven by the conveying chain, when the axle housing moves to the position below the first cross rod through the conveying chain, the air vent part is communicated with the air guide end, and alkaline gas is introduced into the axle housing through the air guide end; then first nozzle is opened, and phenolphthalein test solution spouts to axle housing surface from first nozzle this moment, if the phenolphthalein test solution on the surface of axle housing has red to appear, then explains red place appears in axle housing, has the phenomenon of gas leakage, through this device, detects the time measuring, can appear red mark line in the position of axle housing gas leakage, mark gas leakage position that like this can be accurate makes things convenient for the staff to fix a position gas leakage position fast.

Drawings

FIG. 1 is a front cross-sectional view of an embodiment of the present invention;

FIG. 2 is a side view of an embodiment of the present invention;

FIG. 3 is a schematic view of the connection of an adjustment plate and a vent rod in an embodiment of the present invention;

FIG. 4 is a schematic diagram of the structure of the upper and lower baffles in accordance with an embodiment of the present invention;

FIG. 5 is an elevation view of a through hole in an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a support frame in an embodiment of the invention.

Wherein, 1-a base, 2-a transmission chain, 3-a transmission rod, 4-a first cross rod, 5-a first nozzle, 6-a fixed block, 7-a first cylinder, 8-a gas tank, 9-a gas pump, 10-a separation plate, 11-an outlet, 12-a detection groove, 13-a second cross rod, 14-a second nozzle, 15-an adjusting plate and 16-a ventilation rod, 17-a second cylinder, 18-an adjusting groove, 19-an air pipe, 20-an electromagnetic valve, 21-a ventilation cavity, 22-an upper clapboard, 23-an upper chute, 24-a through hole, 25-a lower clapboard, 26-a lower chute, 27-a spring, 28-a motor, 29-a threaded rod, 30-a support frame, 31-a pressure sensor and 32-a stabilizer bar.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

In view of the above objects, a first aspect of the present invention provides an embodiment of a seal inspection device for an axle housing, as shown in FIG. 1, comprising

A base 1;

the conveying device comprises a conveying chain 2, a plurality of conveying rods 3 fixed on the conveying chain 2 and at least two fixing blocks 6 fixed on the outer side surface of an axle housing, wherein hooks are arranged at the bottoms of the conveying rods 3 and used for hooking the fixing blocks 6;

the device comprises at least one first cross rod 4 fixed on the base 1 through a fixing piece and a plurality of first nozzles 5 fixed on the first cross rod 4, wherein the first nozzles 5 are communicated with a liquid storage cavity filled with phenolphthalein test liquid through a guide pipe, the liquid storage cavity is positioned above the first nozzles 5, and when the axle housing moves to the position below the first cross rod 4, the first nozzles 5 spray the phenolphthalein test liquid;

the air guide end is fixed on the outer surface of the axle housing and communicated with the interior of the axle housing;

the axle housing is driven by the conveying chain 2, when the axle housing moves to the position below the first cross rod 4 through the conveying chain 2, the air vent part is communicated with the air guide end, and alkaline gas is introduced into the axle housing through the air guide end; then first nozzle 5 is opened, and phenolphthalein test solution spouts the axle housing surface from first nozzle 5 this moment, if phenolphthalein test solution on the surface of axle housing has red to appear, then explains red place appears in the axle housing, has the phenomenon of gas leakage, through this device, detects the time measuring, red mark line can appear in the position of axle housing gas leakage, mark gas leakage position that like this can be accurate, make things convenient for the staff to fix a position gas leakage position fast, here, alkaline gas can adopt the ammonia.

As an embodiment, as shown in fig. 2, two first cross bars 4 are provided and are symmetrically arranged; when axle housing removed extremely 1 top of base, axle housing are located the below of two 4 intermediate positions of first horizontal pole, when spraying phenolphthalein test solution at first nozzle 5 like this, can be quick with the both sides of axle housing outside surface all quick spray phenolphthalein test solution, can effectively reduce check-out time, improve detection efficiency.

As an embodiment, as shown in fig. 2, the liquid storage device further comprises at least one second cross bar 13 and a plurality of second nozzles 14, wherein the second cross bar 13 is fixed on the base 1 through a fixing member, and the second nozzles 14 are communicated with the liquid storage cavity through a conduit; when the axle housing is moved to below the first cross bar 4, the second cross bar 13 is located below the axle housing, and the second nozzle 14 faces the side surface below the axle housing.

Because axle housing's outside surface is convex structure, consequently spraying phenolphthalein test solution in the below with axle housing that only leans on first nozzle 5 to be difficult quick, consequently, in this embodiment, through second nozzle 14, can be quick with the below of axle housing spray phenolphthalein test solution, improve detection efficiency.

As an embodiment, as shown in fig. 2, the device comprises a partition board 10 fixed on a base 1, wherein a detection groove 12 is arranged in the partition board; the detection groove 12 penetrates through the left side surface, the right side surface and the upper end surface of the isolation plate 10, and an outlet 11 is formed in the bottom of the detection groove; the first cross bar 4 and the second cross bar 13 are both positioned in the detection groove 12.

In this embodiment, the phenolphthalein test solution can be prevented from being sprayed to the outside by the detection groove 12, and the phenolphthalein test solution that is not adhered to the axle housing is discharged from the outlet 11.

As an embodiment, as shown in fig. 2 and 3, the ventilation part includes a first cylinder 7 fixed to the base 1 through a connecting block, an air tank 8 fixed to the base 1, an air pump 9 having an air inlet communicated with an outlet of the air tank 8, a ventilation rod 16 having a ventilation cavity 21 therein, and an air pipe 19; one end of the ventilation rod 16 is connected with the output shaft of the first air cylinder 7, the other end of the ventilation rod passes through a through hole 24 formed in the side face of the partition board 10 and extends into the detection groove 12, the opening of the ventilation cavity 21 faces the end face of the ventilation rod 16 located in the detection groove 12, the diameter of the air guide end is equal to that of the ventilation cavity 21, alkaline air is filled in the air tank 8, and the outlet of the air pump 9 is communicated with the ventilation cavity 21 through the air pipe 19.

In the embodiment, when the axle housing moves to the detection groove 12, the air guide end is opposite to the opening of the air cavity 21, and the first air cylinder 7 drives the air rod 16 to move towards the air guide end, and finally the air guide end is inserted into the air cavity 21; after the detection is finished, the air pump 9 is started, alkaline gas in the air tank 8 passes through the air pipe 19 and then enters the axle housing after passing through the ventilation cavity 21 and the air guide end, after sufficient alkaline gas is introduced into the axle housing, the phenolphthalein test solution is sprayed to the surface of the axle housing by the first nozzle 5 and the second nozzle 14 for detection, and after the detection is finished, the first air cylinder 7 is restarted to separate the ventilation cavity 21 from the air guide end.

As an embodiment, as shown in fig. 3, the air vent device comprises an electromagnetic valve 20, wherein the electromagnetic valve 20 is fixed on the air vent rod 16 and used for controlling the on-off of the air vent cavity 21, and the fixing position of the electromagnetic valve 20 is located between the communication position of the air pipe 19 and the air vent cavity 21 and the opening of the air vent cavity 21.

In this embodiment, after one axle housing is detected and is accomplished, solenoid valve 20 will ventilate chamber 21 and cut off, make alkaline gas temporarily can not flow in ventilating chamber 21, wait that next axle housing gets into and detect groove 12 to ventilate chamber 21 and air guide end combination back, solenoid valve 20 opens, can avoid like this that air pump 9 frequently opens and close.

As an embodiment, as shown in fig. 2, 3, 4 and 5, the air conditioner comprises an adjusting plate 15, a second air cylinder 17, an upper partition plate 22, a lower partition plate 25 and a spring 27, wherein one side of the adjusting plate is fixed on the first air cylinder 7, the upper side wall of the through hole 24 is provided with an upper chute 23, the lower side wall of the through hole 24 is provided with a lower chute 26, the upper partition plate 22 is slidably connected with the upper chute 23, the lower partition plate 25 is slidably connected with the lower chute 26, the lower end of the lower partition plate 25 is fixedly connected with one end of the spring 27, the other end of the spring 27 is fixedly connected with the bottom of the lower chute 26, and the width of the upper partition plate 22 and the width of the lower partition plate 25 are both equal to the width of; the second cylinder 17 is fixed above the upper chute 23, and the output shaft of the second cylinder is fixedly connected with the upper end part of the upper clapboard 22; the air bar 16 is positioned between the upper partition plate 22 and the lower partition plate 25, the lower end surface of the upper partition plate 22 and the upper end surface of the lower partition plate 25 are respectively provided with a semicircular groove matched with the side surface of the air bar 16, the air bar 16 passes through the semicircular grooves, and when the second air cylinder 17 is started, the air bar 16 moves in the vertical direction; the adjusting plate 15 is provided with an adjusting groove 18 on the side facing the ventilation bar 16, and the end of the ventilation bar 16 is slidably connected with the adjusting groove 18.

Considering the size of the axle housing is different, in this embodiment, when the axle housing detected at present is smaller than the axle housing diameter detected at last, the second cylinder 17 is activated to move the upper partition 22 upward, the lower partition 25 moves upward under the elastic force of the spring 27, and simultaneously drives the ventilation rod 16 to move upward in the adjustment groove 18, through the above actions, the through hole 24 is always kept sealed by the upper partition 22 and the lower partition 25, and when the ventilation cavity 21 is adjusted to be opposite to the air guide end, the second cylinder 17 stops driving; when the diameter of the axle housing detected at present is larger than that of the axle housing detected at last time, the second air cylinder 17 is started to enable the upper partition plate 22 to move downwards, the lower partition plate 25 overcomes the elastic force of the spring 27 to move downwards and simultaneously drives the ventilation rod 16 to move downwards in the adjusting groove 18, and when the ventilation cavity 21 is adjusted to be opposite to the air guide end, the second air cylinder 17 stops driving; the detection device can be adapted to axle housings of different specifications by the method.

Considering that the axle housing may shake during the process of combining the air vent cavity 21 with the air guide end, as an embodiment, as shown in fig. 6, the axle housing includes a motor 28 fixed at the bottom of the detection groove 12, a threaded rod 29 connected with an output shaft of the motor 28 through a coupling, a support frame 30, a pressure sensor 31 and a stabilizer bar 32, wherein the support frame 30 includes a transverse plate and a vertical plate, the two ends of the transverse plate are provided with the vertical plate, the threaded rod 29 is in threaded connection with the middle position of the transverse plate, one end of the stabilizer bar 32 is fixed at the bottom of the detection groove 12, and the other end of the stabilizer bar 32 passes through the transverse plate and is in sliding connection; when axle housing moved to detecting in the groove 12, support frame 30 was located axle housing's below, and two risers were located axle housing's both sides, the top of riser was equipped with pressure sensor 31, pressure sensor 31 and motor 28 electric connection.

In this embodiment, after the axle housing is moved into the detection slot 12, the motor 28 is started to drive the support frame 30 to move upward, and when the pressure sensor 31 senses the pressure, the motor 28 stops driving, so that the axle housing can be stabilized by the support frame 30.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the idea of the invention, also technical features in the above embodiments or in different embodiments may be combined and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity. Therefore, any omissions, modifications, substitutions, improvements and the like that may be made without departing from the spirit and principles of the invention are intended to be included within the scope of the invention.