1. A device for detecting the inner container of a hydrogen storage cylinder based on a single coil probe is characterized by comprising:

the detection assembly is used for carrying out nondestructive detection on the inner wall of the inner container;

the first driving assembly is used for driving the detection assembly to advance in the inner container.

2. The device for detecting the inner container of the hydrogen storage cylinder based on the single coil probe as claimed in claim 1, wherein the first driving assembly is a first piston cylinder, the detecting assembly is arranged at the top of a piston rod of the first piston cylinder, and a cylinder body of the first piston cylinder is fixedly arranged on a bracket outside the hydrogen storage cylinder;

the detection assembly comprises a main rod, a first connecting ring, a second driving assembly and a plurality of supporting assemblies;

the first connecting ring is sleeved on the main rod;

the supporting assembly comprises a first connecting rod and a second connecting rod, one end of the first connecting rod is hinged with the top end of the main rod, and the other end of the first connecting rod is hinged with the middle part of the second connecting rod; the tail end of the main rod is connected with the first driving component; one end of the second connecting rod is hinged with the first connecting ring, and the plurality of supporting components are uniformly arranged along the circumferential direction of the main rod; fixing the conducting wires at the end parts of all the second connecting rods to form a coil which is used as an eddy current nondestructive testing probe;

the second driving assembly can drive the first connecting ring to move along the length direction of the main rod, when the first connecting ring is close to the top end of the main rod, the plurality of supporting assemblies are unfolded, the whole body is in an umbrella rib shape, and at the moment, the coil is in a circular shape and is close to the inner wall of the inner container; when the first link ring moves away from the top end of the main rod, the plurality of support members and the coil are gathered together.

3. The apparatus for sensing the inner liner of a hydrogen storage cylinder based on the single-coil probe as claimed in claim 2, wherein the top end of the second connecting rod is provided with an elastic member, the other end of the elastic member is provided with a wear-resistant rigid ball, the coil is connected with the elastic member, and the connection point is located at the connection position of the elastic member and the wear-resistant rigid ball.

4. The device for detecting the inner liner of a hydrogen storage cylinder based on the single-coil probe as claimed in claim 3, wherein all the second connecting rods are covered with cloth, the coils are fixedly arranged on the cloth, the plurality of supporting components and the cloth are in an umbrella shape after being unfolded, and the circular coils are positioned at the edge of the umbrella cloth.

5. The apparatus for detecting the inner bladder of a hydrogen storage cylinder based on a single-coil probe as claimed in claim 4, wherein the main rod is a polished rod, and the first connecting ring is movably sleeved on the polished rod; the second driving assembly is a second piston cylinder which is arranged in parallel with the polish rod; the tail end of the polish rod and the cylinder body of the second piston cylinder are fixedly arranged at the top of the piston rod of the first piston cylinder; a piston rod of the second piston cylinder is connected with the first connecting ring; the first connecting ring is pushed to move along the polished rod by the expansion of the piston rod.

6. The device for detecting the inner container of the hydrogen storage cylinder based on the single-coil probe as claimed in claim 4, wherein the main rod is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving assembly is a second piston cylinder, the second piston cylinder is arranged in the circular tube, and the tail end of the circular tube and the cylinder body of the second piston cylinder are both fixedly arranged at the top of the piston rod of the first piston cylinder; fixedly connected with stopper on the first connecting ring, the one end of stopper is passed the spout and is connected with the piston rod of second piston cylinder, and the flexible first connecting ring of drive of piston rod moves along mobile jib length direction.

7. The device for detecting the inner container of the hydrogen storage cylinder based on the single-coil probe as claimed in claim 4, wherein the main rod is a first lead screw, the first connecting ring is in threaded connection with a second lead screw, the top end of the first lead screw is rotatably connected with a second connecting ring through a bearing, one end of the first connecting rod is hinged with the second connecting ring, and the other end of the first connecting rod is hinged with the middle part of the second connecting rod; a guide rod is arranged in parallel with the first screw rod, one end of the guide rod is fixedly connected with the second connecting ring, and the other end of the guide rod is connected with the top of a piston rod of the first piston cylinder; the first connecting ring is provided with a through hole, and the first connecting ring is movably sleeved on the guide rod through the through hole;

the second driving assembly is a first motor, the first motor is fixedly arranged at the top of a piston rod of the first piston cylinder, a rotating shaft of the first motor is fixedly connected with the second lead screw, and the first motor drives the second lead screw to rotate to drive the first connecting ring to move along the length directions of the second lead screw and the guide rod.

8. The device for detecting the inner liner of the hydrogen storage cylinder based on the single-coil probe as claimed in claim 4, wherein the main rod is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving component is a first motor, the first motor is arranged in the circular tube, and the tail end of the circular tube and the first motor are both fixedly arranged at the top of a piston rod of the first piston cylinder; the second lead screw is arranged in the round pipe and arranged in parallel with the round pipe, the top end of the second lead screw is rotatably connected with the top end of the round pipe through a bearing, the other end of the second lead screw is fixedly connected with an output shaft of the first motor, a thread connecting sleeve is arranged on the second lead screw and provided with a third connecting ring, a limiting block is fixedly connected onto the first connecting ring, one end of the limiting block penetrates through the sliding groove and is fixedly connected with the third connecting ring, the first motor drives the second lead screw to rotate, the third connecting ring is driven to move along the length direction of the second lead screw, and the first connecting ring is pushed to move together.

9. The method for detecting the device for detecting the inner liner of the hydrogen storage cylinder based on the single coil probe according to any one of claims 1 to 8, which is characterized by comprising the following steps:

step one, placing a detection assembly into an inner container, wherein a first piston cylinder and a support are positioned outside a hydrogen storage cylinder;

step two, a second driving assembly is started through a first switch arranged outside the hydrogen storage cylinder, the second driving assembly drives the first connecting ring to move towards the top end of the main rod, the plurality of supporting assemblies and the coils are driven to be gradually expanded until a rigid ball at the top end of the second connecting rod is contacted with the inner wall of the liner, the coils are close to the inner wall of the liner, and the whole liner is in an umbrella shape; then the second driving assembly is closed through the first switch, and the relative position of the first connecting ring and the main rod is kept fixed;

step three, starting the first piston cylinder, extending a piston rod of the first piston cylinder to drive the whole detection assembly to move forward in the inner container, carrying out nondestructive detection on the inner container by the nondestructive detection probe, and transmitting detection data to a control terminal arranged outside the hydrogen storage cylinder;

after the inner wall of the inner container is completely detected, the second driving assembly is started again through the first switch, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod, and the plurality of supporting assemblies and the coils are driven to be gradually folded; then a piston rod of the first piston cylinder is controlled to begin to retract, and the whole detection assembly is driven to move towards the bottle mouth of the inner container;

and step five, turning off the power supply, connecting the whole detection device with the hydrogen storage cylinder, fixedly connecting the detection device with the hydrogen storage cylinder, separating the detection device from the hydrogen storage cylinder, taking out the detection device from the inner container, and then putting the detection device into the containing box.

Background

The carbon fiber winding gas storage bottle comprises a carbon fiber winding layer, an anti-galvanic corrosion layer and an aluminum inner container. The innermost layer of the gas cylinder is an inner container, and the innermost layer of the gas cylinder bears the internal pressure of the gas in the cylinder and simultaneously bears the tension of the composite material fibers. The aluminum inner container only bears a small part of the gas pressure in the bottle, and most of the pressure is born by the external carbon fiber. The inner container of the prior hydrogen storage cylinder at home is generally made of seamless aluminum, and the aluminum material has the advantages of light weight, good compatibility with hydrogen, hydrogen embrittlement resistance, leakage prevention, high damage tolerance, wide temperature application range, proper price and the like. The fiber reinforced composite material layer is wrapped outside the aluminum inner container and is composed of carbon fibers and resin materials, and the fiber reinforced composite material layer is a typical composite material laminated plate structure: the structure is composed of a plurality of layers of unidirectional fiber composite materials, the winding angles of each layer of fiber are different, and the layer has the main function of ensuring that the gas cylinder has enough strength under the action of higher internal pressure. In the integral structure of the gas cylinder, the carbon fiber winding layer bears most of pressure load, about 75-95%.

Because the inner bag outside is twined by carbon fiber and glass fiber, and thickness is more than 15mm, and carbon fiber and glass fiber twine magnetic permeability, consequently current nondestructive test technique can't detect carbon fiber winding hydrogen storage cylinder, but this hydrogen storage cylinder wholly bears the pressure big, in case the accident takes place, the consequence is beyond the assumption. Therefore, a new nondestructive testing device is continuously designed to meet the testing requirements.

Disclosure of Invention

The invention aims to provide a device and a method for detecting a hydrogen storage cylinder liner based on a single-coil probe, and solves the technical problems that carbon fiber wound hydrogen storage cylinders cannot be detected and the potential risk is high in the prior art.

In order to solve the problems, the invention is realized by the following technical scheme:

a device for detecting an inner container of a hydrogen storage cylinder based on a single coil probe comprises:

the detection assembly is used for carrying out nondestructive detection on the inner wall of the inner container;

the first driving assembly is used for driving the detection assembly to advance in the inner container.

By arranging the detection device, the liner is subjected to nondestructive detection from the inside of the hydrogen storage cylinder, the problem that the carbon fiber wound hydrogen storage cylinder cannot be detected in the prior art is solved, and the safety risk of the carbon fiber wound hydrogen storage cylinder is greatly reduced.

The first driving assembly is a first piston cylinder, the detection assembly is arranged at the top of a piston rod of the first piston cylinder, and a cylinder body of the first piston cylinder is fixedly arranged on a support outside the hydrogen storage cylinder;

the detection assembly comprises a main rod, a first connecting ring, a second driving assembly and a plurality of supporting assemblies;

the first connecting ring is sleeved on the main rod;

the supporting assembly comprises a first connecting rod and a second connecting rod, one end of the first connecting rod is hinged with the top end of the main rod, and the other end of the first connecting rod is hinged with the middle part of the second connecting rod; the tail end of the main rod is connected with the first driving component; one end of the second connecting rod is hinged with the first connecting ring, and the plurality of supporting components are uniformly arranged along the circumferential direction of the main rod; fixing the conducting wires at the end parts of all the second connecting rods to form a coil which is used as an eddy current nondestructive testing probe;

the second driving assembly can drive the first connecting ring to move along the length direction of the main rod, when the first connecting ring is close to the top end of the main rod, the plurality of supporting assemblies are unfolded, the whole body is in an umbrella rib shape, and at the moment, the coil is in a circular shape and is close to the inner wall of the inner container; when the first link ring moves away from the top end of the main rod, the plurality of support members and the coil are gathered together.

Because the opening of the hydrogen storage cylinder is small in size, the second driving assembly is not easy to put into the liner and take out of the liner, the main rod, the second driving assembly, the first connecting ring and the plurality of supporting assemblies are arranged, and the plurality of supporting assemblies are folded by the second driving assembly when entering or exiting the liner; when the detection probe enters the inner container for detection, the plurality of support groups are spread by the second driving assembly, the whole body is in an umbrella rib shape, and the nondestructive detection probe is in contact with or close to the inner wall of the inner container.

In addition, the length of the second connecting rod is larger than that of the first connecting rod, the nondestructive testing probe is arranged at the end part of the second connecting rod, after detection and receiving are carried out, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod to drive the plurality of supporting assemblies to be gradually folded, the nondestructive testing probe is folded at the top end of the main rod, the end is large in size, the first connecting ring moves to be close to the top end of the first lead screw, the end is small in size, the whole testing assembly is taken out of the inner container, and the testing probe cannot be clamped at the bottleneck.

In the invention, the conducting wires are fixed at the end parts of all the second connecting rods to form a coil which is used as an eddy current nondestructive testing probe, namely, only one large coil is required to be used as the nondestructive testing probe in the testing assembly. Consequently only need the flexible of the piston rod of first piston cylinder, just can realize that the coil is pressed close to the inner bag inner wall and removes and carry out nondestructive test, convenient operation, detection device simple structure compares with a plurality of probe detection device and detects output data fewly, is convenient for look over.

Further optimize, the top of second connecting rod is provided with the elastic component, and the other end of elastic component is provided with wear-resisting rigid ball, and the coil is connected with the elastic component, and the tie point is located the junction of elastic component and wear-resisting rigid ball.

Because the inner wall of inner bag is not necessarily level and smooth, its terminal surface also does not necessarily be standard circular, through setting up the elastic component, plays the cushioning effect, guarantees that every equal rigidity ball and inner bag inner wall contact, ensures that whole coil is the same to the clearance of inner bag inner wall, improves and detects the precision. In addition, through setting up wear-resisting rigid ball, make it be the point face contact with the inner bag, whole detection assembly can go on smoothly in the in-process that advances during the detection, reduces situations such as jamming, improves detection efficiency.

Further optimize, all second connecting rods are gone up to cover and are equipped with cloth, and the coil is fixed to be set up on cloth, is umbelliform after a plurality of supporting components and cloth are propped open, and circular coil is located the edge of umbelliform cloth.

The second connecting rod is covered with the cloth, and the coil is fixedly arranged on the cloth, so that the connection is firmer and the coil is not easy to fall off; in addition, the coil can be ensured to be more standard circular after being unfolded, so that the gaps of each section of arc line of the coil on the inner wall of the inner container are the same, and the detection precision is improved.

Further optimization, the main rod is a polished rod, and the first connecting ring is movably sleeved on the polished rod; the second driving assembly is a second piston cylinder which is arranged in parallel with the polish rod; the tail end of the polish rod and the cylinder body of the second piston cylinder are fixedly arranged at the top of the piston rod of the first piston cylinder; a piston rod of the second piston cylinder is connected with the first connecting ring; the first connecting ring is pushed to move along the polished rod by the expansion of the piston rod.

The main rod is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving assembly is a second piston cylinder, the second piston cylinder is arranged in the circular tube, and the tail end of the circular tube and a cylinder body of the second piston cylinder are fixedly arranged at the top of a piston rod of the first piston cylinder; fixedly connected with stopper on the first connecting ring, the one end of stopper is passed the spout and is connected with the piston rod of second piston cylinder, and the flexible first connecting ring of drive of piston rod moves along mobile jib length direction.

The main rod is a first lead screw, the first connecting ring is in threaded connection with the second lead screw, the top end of the first lead screw is rotatably connected with a second connecting ring through a bearing, one end of the first connecting rod is hinged with the second connecting ring, and the other end of the first connecting rod is hinged with the middle part of the second connecting rod; a guide rod is arranged in parallel with the first screw rod, one end of the guide rod is fixedly connected with the second connecting ring, and the other end of the guide rod is connected with the top of a piston rod of the first piston cylinder; the first connecting ring is provided with a through hole, and the first connecting ring is movably sleeved on the guide rod through the through hole;

the second driving assembly is a first motor, the first motor is fixedly arranged at the top of a piston rod of the first piston cylinder, a rotating shaft of the first motor is fixedly connected with the second lead screw, and the first motor drives the second lead screw to rotate to drive the first connecting ring to move along the length directions of the second lead screw and the guide rod.

Preferably, the main rod is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving assembly is a first motor, the first motor is arranged in the circular tube, and the tail end of the circular tube and the first motor are fixedly arranged at the top of a piston rod of the first piston cylinder; the second lead screw is arranged in the round pipe and arranged in parallel with the round pipe, the top end of the second lead screw is rotatably connected with the top end of the round pipe through a bearing, the other end of the second lead screw is fixedly connected with an output shaft of the first motor, a thread connecting sleeve is arranged on the second lead screw and provided with a third connecting ring, a limiting block is fixedly connected onto the first connecting ring, one end of the limiting block penetrates through the sliding groove and is fixedly connected with the third connecting ring, the first motor drives the second lead screw to rotate, the third connecting ring is driven to move along the length direction of the second lead screw, and the first connecting ring is pushed to move together.

The detection method based on the device for detecting the inner container of the hydrogen storage cylinder based on the single-coil probe comprises the following steps:

step one, placing a detection assembly into an inner container, wherein a first piston cylinder and a support are positioned outside a hydrogen storage cylinder;

step two, a second driving assembly is started through a first switch arranged outside the hydrogen storage cylinder, the second driving assembly drives the first connecting ring to move towards the top end of the main rod, the plurality of supporting assemblies and the coils are driven to be gradually expanded until a rigid ball at the top end of the second connecting rod is contacted with the inner wall of the liner, the coils are close to the inner wall of the liner, and the whole liner is in an umbrella shape; then the second driving assembly is closed through the first switch, and the relative position of the first connecting ring and the main rod is kept fixed;

step three, starting the first piston cylinder, extending a piston rod of the first piston cylinder to drive the whole detection assembly to move forward in the inner container, carrying out nondestructive detection on the inner container by the nondestructive detection probe, and transmitting detection data to a control terminal arranged outside the hydrogen storage cylinder;

after the inner wall of the inner container is completely detected, the second driving assembly is started again through the first switch, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod, and the plurality of supporting assemblies and the coils are driven to be gradually folded; then a piston rod of the first piston cylinder is controlled to begin to retract, and the whole detection assembly is driven to move towards the bottle mouth of the inner container;

and step five, turning off the power supply, connecting the whole detection device with the hydrogen storage cylinder, fixedly connecting the detection device with the hydrogen storage cylinder, separating the detection device from the hydrogen storage cylinder, taking out the detection device from the inner container, and then putting the detection device into the containing box.

Compared with the prior art, the invention has the beneficial effects that:

1. by arranging the detection device, the liner is subjected to nondestructive detection from the inside of the hydrogen storage cylinder, the problem that the carbon fiber wound hydrogen storage cylinder cannot be detected in the prior art is solved, and the safety risk of the carbon fiber wound hydrogen storage cylinder is greatly reduced.

2. Because the opening of the hydrogen storage cylinder is small in size, the second driving assembly is not easy to put into the liner and take out of the liner, the main rod, the second driving assembly, the first connecting ring and the plurality of supporting assemblies are arranged, and the plurality of supporting assemblies are folded by the second driving assembly when entering or exiting the liner; when the detection probe enters the inner container for detection, the plurality of support groups are spread by the second driving assembly, the whole body is in an umbrella rib shape, and the nondestructive detection probe is in contact with or close to the inner wall of the inner container. According to the invention, the length of the second connecting rod is greater than that of the first connecting rod, the nondestructive testing probe is arranged at the end part of the second connecting rod, after detection and receiving are carried out, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod to drive the plurality of supporting assemblies to be gradually folded, the nondestructive testing probe is folded at the top end of the main rod, the end is large in size, the first connecting ring moves to be close to the top end of the first lead screw, the end is small in size, the whole testing assembly is taken out of the inner container, and the testing probe cannot be clamped at the bottleneck.

3. In the invention, the conducting wires are fixed at the end parts of all the second connecting rods to form a coil which is used as an eddy current nondestructive testing probe, namely, only one large coil is required to be used as the nondestructive testing probe in the testing assembly. Consequently only need the flexible of the piston rod of first piston cylinder, just can realize that the coil is pressed close to the inner bag inner wall and removes and carry out nondestructive test, convenient operation, detection device simple structure compares with a plurality of probe detection device and detects output data fewly, is convenient for look over.

4. Through setting up the elastic component, play the cushioning effect, guarantee every equal rigidity ball and inner bag inner wall contact, guarantee that every nondestructive test probe is the same to the clearance of inner bag inner wall, improve and detect the precision. In addition, through setting up wear-resisting rigid ball, make it be the point face contact with the inner bag, whole detection assembly can go on smoothly in the in-process that advances during the detection, reduces situations such as jamming, improves detection efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a device for detecting an inner container of a hydrogen storage cylinder based on a single coil probe in the first embodiment.

Fig. 2 is a top view of the inspection assembly of fig. 1 shown expanded.

Fig. 3 is an enlarged view of the detection assembly of fig. 1.

Fig. 4 is a schematic structural diagram of the detection assembly in a folded state according to an embodiment.

Fig. 5 is a schematic structural view of a device for detecting an inner container of a hydrogen storage cylinder based on a single coil probe in the second embodiment.

Fig. 6 is an enlarged view of the detection assembly of fig. 5.

Fig. 7 is a schematic structural view of a device for detecting an inner container of a hydrogen storage cylinder based on a single coil probe in the third embodiment.

Fig. 8 is an enlarged view of the detection assembly of fig. 7.

Fig. 9 is a schematic structural view of the apparatus for detecting the inner liner of the hydrogen storage cylinder based on the single coil probe in the fourth embodiment.

Fig. 10 is an enlarged view of the detection assembly of fig. 9.

FIG. 11 is a flow chart of a detection method of the device for detecting the inner liner of a hydrogen storage cylinder based on a single coil probe according to the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

The first embodiment is as follows:

as shown in fig. 1 to 4, an apparatus for detecting an inner container of a hydrogen storage cylinder based on a single coil probe comprises:

the detection assembly 1 is used for carrying out nondestructive detection on the inner wall of the inner container;

a first driving assembly 2 for driving the detection assembly to advance in the inner container.

By arranging the detection device, the liner is subjected to nondestructive detection from the inside of the hydrogen storage cylinder, the problem that the carbon fiber wound hydrogen storage cylinder cannot be detected in the prior art is solved, and the safety risk of the carbon fiber wound hydrogen storage cylinder is greatly reduced.

In this embodiment, the first driving assembly 2 is a first piston cylinder, the detecting assembly 1 is disposed on the top of a piston rod 21 of the first piston cylinder, and a cylinder body 22 of the first piston cylinder is fixedly disposed on a bracket outside a hydrogen storage cylinder.

In the present embodiment, the detecting assembly 2 includes a main rod 12, a first connecting ring 13, a second driving assembly, and eight supporting assemblies; the first connecting ring 13 is sleeved on the main rod 12.

The support component comprises a first connecting rod 18 and a second connecting rod 17, one end of the first connecting rod 18 is hinged with the top end of the main rod 12, and the other end of the first connecting rod 18 is hinged with the middle part of the second connecting rod 17; the tail end of the main rod 12 is connected with a first driving component; one end of the second connecting rod is hinged with the first connecting ring, and the plurality of supporting components are uniformly arranged along the circumferential direction of the main rod; the lead wires are fixed at the end parts of all the second connecting rods to form a coil 19 which is used as an eddy current nondestructive testing probe.

The second driving assembly can drive the first connecting ring to move along the length direction of the main rod, when the first connecting ring is close to the top end of the main rod, the plurality of supporting assemblies are unfolded, the whole body is in an umbrella rib shape, and at the moment, the coil is in a circular shape and is close to the inner wall of the inner container; when the first link ring moves away from the top end of the main rod, the plurality of support members and the coil are gathered together.

Because the opening of the hydrogen storage cylinder is small in size, the second driving assembly is not easy to put into the liner and take out of the liner, the main rod, the second driving assembly, the first connecting ring and the plurality of supporting assemblies are arranged, and the plurality of supporting assemblies are folded by the second driving assembly when entering or exiting the liner; when the detection probe enters the inner container for detection, the plurality of support groups are spread by the second driving assembly, the whole body is in an umbrella rib shape, and the nondestructive detection probe is in contact with or close to the inner wall of the inner container. According to the invention, the length of the second connecting rod is greater than that of the first connecting rod, the nondestructive testing probe is arranged at the end part of the second connecting rod, after detection and receiving are carried out, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod to drive the plurality of supporting assemblies to be gradually folded, the nondestructive testing probe is folded at the top end of the main rod, the end is large in size, the first connecting ring moves to be close to the top end of the first lead screw, the end is small in size, the whole testing assembly is taken out of the inner container, and the testing probe cannot be clamped at the bottleneck.

In the invention, the conducting wires are fixed at the end parts of all the second connecting rods to form a coil which is used as an eddy current nondestructive testing probe, namely, only one large coil is required to be used as the nondestructive testing probe in the testing assembly. Consequently only need the flexible of the piston rod of first piston cylinder, just can realize that the coil is pressed close to the inner bag inner wall and removes and carry out nondestructive test, convenient operation, detection device simple structure compares with a plurality of probe detection device and detects output data fewly, is convenient for look over.

In other embodiments, the number of support members may be two, three, four, five, six, etc., as desired.

In this embodiment, the top end of the second connecting rod is provided with an elastic member 102, the other end of the elastic member is provided with a wear-resistant rigid ball 101, the coil 19 is connected with the elastic member, and the connection point is located at the connection position of the elastic member and the wear-resistant rigid ball.

Because the inner wall of inner bag is not necessarily level and smooth, its terminal surface also does not necessarily be standard circular, through setting up the elastic component, plays the cushioning effect, guarantees that every equal rigidity ball and inner bag inner wall contact, ensures that whole coil is the same to the clearance of inner bag inner wall, improves and detects the precision. In addition, through setting up wear-resisting rigid ball, make it be the point face contact with the inner bag, whole detection assembly can go on smoothly in the in-process that advances during the detection, reduces situations such as jamming, improves detection efficiency.

In the present embodiment, the elastic member 102 is a spring. In other embodiments, the elastic member 102 may be a rubber block.

In this embodiment, all the second connecting rods are covered with cloth, the coils are fixedly arranged on the cloth, the plurality of supporting assemblies and the cloth are in an umbrella shape after being unfolded, and the circular coils are located at the edge of the umbrella cloth.

The second connecting rod is covered with the cloth, and the coil is fixedly arranged on the cloth, so that the connection is firmer and the coil is not easy to fall off; in addition, the coil can be ensured to be more standard circular after being unfolded, so that the gaps of each section of arc line of the coil on the inner wall of the inner container are the same, and the detection precision is improved.

In this embodiment, the main rod 12 is a polished rod, and the first connecting ring 13 is movably sleeved on the polished rod; the second driving assembly is a second piston cylinder which is arranged in parallel with the polish rod; the tail end of the polish rod and the cylinder body 104 of the second piston cylinder are both fixedly arranged at the top of the piston rod 21 of the first piston cylinder 2; the piston rod 103 of the second piston cylinder is connected to the first connecting ring 13; the piston rod 103 of the second piston cylinder stretches and retracts to push the first connecting ring to move along the polish rod, so that the aim of expanding or contracting the support frame is fulfilled.

In this embodiment, the piston cylinder is a hydraulic piston cylinder, and in other embodiments, may be a cylinder.

Example two:

in this embodiment, as shown in fig. 5 and 6, the main rod 12 is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving assembly is a second piston cylinder, the second piston cylinder is arranged in the circular tube, and the end of the circular tube and the cylinder body 104 of the second piston cylinder are both fixedly arranged at the top of the piston rod 21 of the first piston cylinder 2; a limiting block 16 is fixedly connected to the first connecting ring 13, one end of the limiting block 16 penetrates through the sliding groove to be connected with a piston rod 103 of the second piston cylinder, and the piston rod 103 of the second piston cylinder stretches and retracts to drive the first connecting ring 13 to move along the length direction of the main rod 12, so that the purpose of expanding or folding the supporting frame is achieved.

The other parts are the same as in the first embodiment.

Example three:

in this embodiment, as shown in fig. 7 and 8, the main rod is 12 a first lead screw, the first connecting ring 13 is in threaded connection with a second lead screw, the top end of the first lead screw is rotatably connected with a second connecting ring 107 through a bearing, one end of the first connecting rod 18 is hinged with the second connecting ring 107, and the other end is hinged with the middle part of the second connecting rod 17; a guide rod 106 is arranged in parallel with the first screw rod, one end of the guide rod 106 is fixedly connected with a second connecting ring 107, and the other end of the guide rod 106 is fixedly connected with the top of the piston rod 21 of the first piston cylinder; the first connecting ring 13 is provided with a through hole, and the first connecting ring 13 is movably sleeved on the guide rod 13 through the through hole.

The second driving assembly is a first motor 11, the first motor 11 is fixedly arranged at the top of a piston rod 21 of the first piston cylinder, a rotating shaft of the first motor is fixedly connected with a second lead screw, and the first motor drives the second lead screw to rotate to drive the first connecting ring to move along the length direction of the second lead screw and the guide rod 106, so that the purpose of expanding or contracting the supporting frame is achieved. The first motor 11 is a servo motor.

The other parts are the same as in the first embodiment.

Example four:

in this embodiment, as shown in fig. 9 and 10, the main rod 12 is a circular tube, a sliding groove is formed in the circular tube along the length direction of the circular tube, the second driving component is the first motor 11, the first motor 11 is disposed in the circular tube 12, and the end of the circular tube and the first motor 11 are both fixedly disposed at the top of the piston rod 21 of the first piston cylinder; be provided with second lead screw 14 in the pipe, second lead screw 14 and pipe 12 parallel arrangement, the top of second lead screw 14 is passed through the bearing and is connected with the top rotation of pipe 12, the other end links firmly with the output shaft of first motor, threaded connection cover is equipped with third go-between 15 on the second lead screw 14, fixedly connected with stopper 16 on the first go-between 13, spout and third go-between 15 fixed connection are passed to stopper 16's one end, first motor 11 drive second lead screw 14 rotates, it removes along second lead screw 14 length direction to drive third go-between 15, thereby promote first go-between 13 and remove together, play the mesh that struts or draws in the support frame. The first motor is a servo motor.

The other parts are the same as in the first embodiment.

Example five:

as shown in fig. 11, the detection method based on the device for detecting the inner liner of the hydrogen storage cylinder based on the single coil probe comprises the following steps:

s1, placing the detection assembly into the inner container, and positioning the first piston cylinder and the bracket outside the hydrogen storage cylinder;

s2, a second driving assembly is started through a first switch arranged outside the hydrogen storage cylinder, the second driving assembly drives the first connecting ring to move towards the top end of the main rod, the plurality of supporting assemblies and the coils are driven to be gradually unfolded until the rigid ball at the top end of the second connecting rod is contacted with the inner wall of the liner, the coils are close to the inner wall of the liner, and the whole liner is in an umbrella shape; then the second driving assembly is closed through the first switch, and the relative position of the first connecting ring and the main rod is kept fixed;

s3, starting the first piston cylinder, extending a piston rod of the first piston cylinder to drive the whole detection assembly to move forward in the inner container, carrying out nondestructive detection on the inner container by the nondestructive detection probe, and transmitting detection data to a control terminal arranged outside the hydrogen storage cylinder;

s4, after the inner wall of the inner container is completely detected, the second driving assembly is started again through the first switch, the second driving assembly drives the first connecting ring to move towards the tail end of the main rod, and the plurality of supporting assemblies and the coils are driven to be gradually folded; then a piston rod of the first piston cylinder is controlled to begin to retract, and the whole detection assembly is driven to move towards the bottle mouth of the inner container;

and S5, turning off the power supply, connecting the whole detection device with the hydrogen storage cylinder, separating the detection device from the hydrogen storage cylinder, taking out the detection device from the inner container, and putting the detection device into the containing box.

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.