CN212210821U - Braking magnetic pole structure for linear eddy current braking device - Google Patents

Abstract

The utility model discloses linear eddy current arresting gear is with braking magnetic pole structure, include: the magnetic motor comprises an iron core, an insulating layer, a coil, a supporting layer, a fixing ribbon, a binding post and a packaging layer, wherein a plurality of grooves in the axial direction are formed in the periphery of the iron core at intervals; the fixing band tightens the coil, and fixes and keeps the coil, the insulating layer and the supporting layer together at the periphery of the iron core. The utility model discloses a place fixed ribbon at iron core outlying rectangle slot, make the aluminium flat wire have more winding spaces, improve the full rate in groove, increase the ampere of turns. The ampere-turn number can be increased by 4%, the braking force can be increased by 0.4%, and the braking force caused by the reduction of the sectional area of the iron core is reduced to 0.2%, so that the braking force is increased by 0.2% net. The rated power of the brake magnetic pole of the utility model is about 3.2kW, the maximum magnetomotive force is 21.7kA, and the requirements of a new generation of magnetic suspension train are met.

Description

Braking magnetic pole structure for linear eddy current braking device

Technical Field

The utility model belongs to the technical field of rail vehicle braking system, concretely relates to braking magnetic pole structure suitable for maglev train.

Background

The existing magnetic suspension train mostly adopts a linear eddy current brake device to carry out emergency braking. The linear eddy current braking technology is characterized in that eddy current is generated on a side guide rail by utilizing a magnetic field generated by electrifying a braking magnetic pole under a high-speed condition, the magnetic field generated by the eddy current is mutually interacted and attracted with an original magnetic field according to Maxwell's law and Lenz's law, so that braking force is generated, and the braking force is finally transmitted to a vehicle bogie through a braking magnetic pole iron core, a magnetic yoke and a pull rod assembly, so that vehicle braking is realized.

The highest speed per hour of the Shanghai magnetic suspension train is 500km/h, the linear eddy current brake device used on the train uses magnetic poles, and the rated magnetomotive force of a single magnetic pole is 20.4 kA. Because space and weight are more strict, the magnetomotive force required to be generated is larger, and the problems of large manufacturing difficulty, high manufacturing cost, large difficulty of winding process and welding process and the like exist in the prior art of adopting the aluminum film winding coil.

The highest running speed of the new generation of magnetic suspension train is 600km/h, and the magnetomotive force required to be provided by the braking magnetic pole is calculated to be as high as 21.7kA according to the deceleration requirement. That is, the ampere-turns increase by 6.4%. Therefore, increasing the ampere-turns (increasing the slot fill factor) is a technical and technological challenge given the constant excitation current and given the space and weight limitations of existing pole structures. From the aspects of technical realization possibility and process guarantee feasibility, two technical schemes can be selected:

film aluminum wire winding coil technology: on the basis of the existing scheme, the number of turns is increased, and the sectional area of the aluminum film is reduced, so that the current density of the aluminum wire is increased, the coil is easily burnt out, the brake failure is caused, and the consequence is serious. The reduction of the thickness of the insulating diaphragm can also increase the slot filling rate, but the thickness of the current diaphragm is equal to that of a paint film of an enameled wire, and the reduction of the thickness can hardly ensure the insulating strength, thereby easily causing short circuit failure. The aluminum film wire winding coil technology has great challenges in increasing the slot filling rate and the ampere-turns, both in the technical realization possibility and in the process guarantee feasibility.

The aluminum flat wire winding coil technology comprises the following steps: firstly, the aluminum flat wire winding coil technology is a mature technology in industry, and both process feasibility and product reliability are guaranteed; secondly, through optimizing the cooperation to iron core geometry and pyrocondensation ribbon, increase the flat line winding space of aluminium, improve the groove full rate and ampere turns, reach the performance data requirement. This is the technical problem that the utility model aims to solve.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that, overcome prior art's above-mentioned shortcoming, provide a linear eddy current arresting gear is with braking magnetic pole structure.

In order to solve the technical problem, the utility model provides a magnetic pole structure, include:

the iron core is used for conducting the magnetic circuit and transmitting braking force, and a plurality of grooves in the axial direction are formed in the periphery of the iron core at intervals;

the insulating layer is wrapped on the periphery of the iron core and used for isolating the coil from the iron core;

the coil is wound on the periphery of the insulating layer by adopting an enameled wire and is used for generating magnetomotive force after being electrified;

the supporting layer is arranged on the periphery of the coil and used for improving the packaging strength;

the fixing band is limited in the groove of the iron core by the insulating layer and is used for tightly binding the coil, fixing the coil, the insulating layer and the supporting layer together and keeping the coil, the insulating layer and the supporting layer at the periphery of the iron core; the fixing ribbon is embedded into the rectangular groove of the iron core, and the purpose of improving the winding space of the aluminum flat wire is achieved. Meanwhile, the mechanical strength of the packaging layer is improved;

the binding post is arranged in the packaging layer on one side and used for leading out an incoming and outgoing wire of the coil and electrifying the coil;

and the packaging layer is wrapped outside the magnetic pole structure and used for sealing the coil and fastening the coil outside the iron core.

Furthermore, the bottom of the binding post is provided with a rectangular groove, the end part of the cable of the coil is electrically connected with the crimping terminal, the crimping terminal is partially embedded into the rectangular groove and is welded and fixed, and the binding post is fixed on one side of the coil by the packaging layer. The purpose of this is to increase the mechanical reliability of the electrical connection.

Furthermore, the fixing ribbon is a thermal shrinkage ribbon, and welded welding interfaces are positioned on the outer side or two sides of the coil or the inner side of the coil is embedded into a groove of the iron core.

In addition, the periphery of the cylinder of the binding post is provided with at least one spline groove which is embedded and contacted with the packaging layer. The purpose of this is to increase the mechanical strength of the encapsulation layer and the terminals, and to improve the convenience and reliability of the pole coil in installation and maintenance.

The utility model discloses a magnetic pole structure mainly comprises epoxy packaging layer, glass fiber net, insulating tape, pyrocondensation ribbon, iron core, coil pack and terminal. The iron core is low-carbon steel with good magnetic conductivity, has good magnetic conductivity and high strength, and mainly has the functions of conducting a magnetic circuit and transmitting braking force; the insulating tape mainly plays a role in electrical isolation and mechanical isolation between the iron core and the enameled wire; the coil assembly is an excitation part and generates strong magnetomotive force after being electrified; the wiring terminal is an electrical interface and introduces external energy into the coil assembly; the coil and the supporting layer (glass fiber net) are subjected to thermal shrinkage fastening by the thermal shrinkage band, so that the frameless coil is prevented from loosening; the addition of the support layer (glass fiber net) can further enhance the mechanical strength of the packaging layer; the epoxy resin packaging layer is an insulating glue layer, so that the mechanical strength in a packaging area is increased, and the insulating and moisture-proof effects are achieved.

The utility model discloses a place fixed ribbon through at iron core outlying rectangle slot to it is opposite to lie in the coil outside with traditional pyrocondensation ribbon welding interface, the utility model discloses place the welding interface of pyrocondensation ribbon in iron core rectangle slot inside, make the aluminium flat wire have more winding spaces, improve the groove fullness rate, increase the ampere of turns. Through finite element electromagnetic simulation calculation, the ampere-turn number of the rectangular groove of the iron core can be increased by 4% and the braking force can be increased by 0.4%. And the reduction of the braking force caused by the reduction of the cross-sectional area of the core due to the grooves is only 0.2%. Overall, the net increase in braking force is 0.2%. That is to say, the utility model discloses under the condition that the brake performance of guaranteeing the coil increases slightly, improve the rectangle slot of iron core and the optimization of encapsulated layer, make the encapsulation degree of difficulty reduce, encapsulation intensity improves, product uniformity and reliability increase.

Because the existing magnetic pole structure adopts an aluminum enameled wire, the binding post is made of brass, the mutual welding ratio of the aluminum enameled wire and the binding post is poor, and the production progress and the welding strength of a product are seriously influenced. The utility model discloses a structural style of being qualified for next round of competitions has avoided above problem betterly, uses on the enameled wire after the depainting and easily welds and the good crimping terminal crimping of electric conductivity with copper, makes wire and crimping terminal rigid combination, then welds crimping terminal and terminal, and the integrality of circuit has been guaranteed to this mode. Due to the good weldability between the crimp terminal (made of copper material, such as H59, H62, etc.) and copper, the mechanical strength of the final weld is very strong.

The magnetic pole structure is particularly suitable for being applied to a linear eddy current braking device of a magnetic suspension train.

The utility model discloses under the condition that does not change original magnetic pole product size, magnetic pole rated power can reach 3.2KW, and the magnetomotive force can reach 21.7kA, and heat-resisting temperature is not less than F level (155 ℃), and the IP grade satisfies IP67, and withstand voltage satisfies AC2.4kV (1 kHz) and lasts 1min intensity, and weight is not more than 24 kg. Can meet the requirements of the new generation of magnetic suspension train on the brake magnetic pole.

Drawings

Fig. 1 is a side view of a brake pole.

Fig. 2 is a top view of the brake pole.

Fig. 3 is a sectional view a-a of fig. 2.

Fig. 4 is an enlarged upper view of fig. 3.

Fig. 5 is a schematic diagram of the line-out structure of the brake pole.

Fig. 6(a) - (d) are schematic diagrams of the studs of the brake pole.

FIG. 7 is a view of the location of the weld interface before and after heat shrinking of the brake pole cross section heat shrink wrap.

FIG. 8 is a graph of brake pole braking force versus ampere-turns.

Fig. 9 is a schematic view of a heat shrink wrap and core arrangement.

Fig. 10 is a schematic view of vacuum potting.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the drawings in the embodiments of the present invention are combined below to clearly and completely describe the technical solutions in the embodiments of the present invention.

As shown in fig. 1 to 4, the magnetic pole structure of the present embodiment is a braking magnetic pole structure suitable for a linear eddy current braking device of a magnetic levitation train, and the size of the magnetic pole structure is as follows: 382.5mm in length, 167mm in width and 93.5mm in height. The brake magnetic pole mainly comprises an iron core 5, an insulating tape 3, a coil 6, a thermal shrinkage band 4, a glass fiber net 2, an epoxy resin packaging layer 1 and a binding post 7.

The iron core 5 is made of low-carbon steel with good magnetic permeability and high strength, and is used for conducting a magnetic circuit and transmitting braking force. Under the condition of meeting the magnetic flux requirement, the chamfer angle of the iron core 5 is not less than 28mm, the condition that the enameled wire protrudes at the junction of the chamfer angle and the straight edge can be prevented, on one hand, the enameled wire is prevented from being easily damaged due to local stress, and on the other hand, the size of the coil is prevented from exceeding the design requirement. The upper part and the lower part of the periphery of the iron core are respectively provided with a circle of concave steps, and the cable of the coil is wound on the periphery of the area between the two steps. The size of the concave step is about 2mm in width and 4mm in height, a certain space is reserved in the step, and after epoxy resin is cured in the space, the displacement of the coil assembly in the axial direction is hindered to a certain extent. In this embodiment, the periphery of the iron core 5 is provided with 8 axial (vertical) grooves 51 at intervals, and the grooves 51 are used for accommodating the thermal shrinkage bandage 4. The cross-section of the groove 51 is rectangular, but it may be semicircular or semi-elliptical.

The insulating tape 3 is wrapped around the core 5 (the area between the two steps) to isolate the coil 4 from the core 5, and to limit the heat shrinkable tape 4 in the groove 51 of the core 5. In this example, a glass fiber tape was used as the insulating tape.

The coil 6 is wound on the periphery of the insulating tape 3 by adopting an aluminum enameled wire and is used for generating magnetomotive force after being electrified.

Glass fiber net 2 sets up in the coil periphery for improve encapsulation intensity, the supporting layer adopts the network structure that intensity is high, makes encapsulation glue can permeate, more inseparabler and firm with coil 6 and the combination of glass fiber net 2.

Heat-shrinkable bands 4 are provided at intervals along the periphery of the core 5 for tightening the coil 6 and fixing and holding the coil 6, the insulating tape 3 and the glass fiber net 2 together at the periphery of the core 5. In this example, heat shrinkable tapes 4 are fixed around the core 5 at intervals by means of the insulating tape 3, and then the coil 6 is wound. This facilitates the fixing of the heat-shrinkable band 4 and the winding of the coil 6. The thickness of the thermal shrinkage band is recommended to be not less than 0.3mm in consideration of size limitation, strength and the like, the thickness of the thermal shrinkage band is 0.6mm, the width of the thermal shrinkage band is 12mm, and in order to accommodate the thermal shrinkage band and a welding interface of the thermal shrinkage band, the width of the groove 51 of the iron core 5 is 13mm, and the depth of the groove is 1 mm. In this embodiment, the welding interface 41 of the heat-shrinkable band 4 is lap-welded on the outside of the coil as shown in fig. 7 (a), and then the heat-shrinkable band 4 is rotated to move the welding interface 41 into the groove of the core 5, and then heat-shrinkable is performed again as shown in fig. 7 (c). Therefore, the winding space of the coil is increased, and the ampere turns can be increased by 4%. Of course, if the weld seam is not moved into the groove of the core 5, heat shrinking is directly performed, as shown in fig. 7 (b), and this is also possible. Fig. 7 (c) is a further optimized scheme.

The basic principle of the utility model is that the magnetic pole braking force calculated according to the electromagnetic theory and the ampere-turns number relation determine the implementation scheme. As can be seen from fig. 8, the relationship between the ampere-turn rating of the magnetic pole and the braking force rating is in a magnetic saturation state. The ampere turn is increased by 30 percent, and the braking force is increased by about 4 percent; the ampere-turns number is reduced by 30%, and the braking force is reduced by about 6%. Adopt the utility model discloses the scheme, the number of ampere turns of coil of braking magnetic pole structure increases 4%, and the multiplicable 0.4% of braking force. And the reduction of the braking force due to the reduction of the core cross-sectional area due to the grooves 51 is only 0.2%. Overall, the net increase in braking force is 0.2%. For the existing products, the net increase of 0.2% of the braking force is a very big breakthrough.

The terminal 7 and the cable end of the coil 6 are electrically connected by a crimp terminal 8, and the epoxy resin encapsulation layer 1 fixes the terminal 7 to the coil 6. In this example, the cable end of the coil 6 is depainted and then crimped to the crimp terminal 8. As shown in fig. 5 and 6, the bottom of the terminal 7 is provided with a rectangular groove 71, the crimp terminal 8 is partially clamped into the rectangular groove 71 and is welded and fixed (B in fig. 5 is a welded part), and the cable end of the coil 6 near the crimp terminal 8 is wrapped with a heat-shrinkable sleeve 9. The periphery of the cylinder of the binding post 7 is provided with at least one spline groove 72 which is embedded and contacted with the packaging layer 1, so that the packaging strength is improved.

Epoxy encapsulation layer 1 wraps up outside magnetic pole structure for seal coil 6 and fasten it outside the iron core, the minimum thickness of epoxy layer should be not less than 1 mm. And encapsulating the product by using the epoxy resin encapsulating layer 1 to fix the coil 6 and the binding post 7. And the mechanical strength in the packaging area is increased, and the effects of insulation and moisture resistance are achieved.

The production process of the brake magnetic pole of the embodiment is as follows:

step 1, arranging a thermal contraction band 4 in a groove 51 along the periphery of an iron core 5, as shown in fig. 9;

step 2, binding an insulating tape 3 made of glass fiber materials on the periphery of the iron core 5, and fixing the thermal shrinkage binding tape 4 in the groove 51 of the iron core 5;

step 3, winding a winding coil 6 outside the insulating tape 3;

step 4, arranging the glass fiber net 2 on the periphery of the coil 6, welding and fixing the welding interface 41 of the binding belt 4, and rotating and moving the thermal shrinkage binding belt to enable the welding interface 41 to be placed in the groove 51 of the iron core 5;

step 5, heating the thermal shrinkage band, tightening the band, fastening the glass fiber net 2 and the coil 6 together, and fastening the coil 6 outside the iron core 5;

step 6, placing a binding post 7 on one side of the coil 6, connecting the cable end of the coil 6 with a crimping terminal 8, inserting the rectangular groove 71 at the bottom of the binding post 7 at the crimping terminal part, welding and fixing, and wrapping a heat-shrinkable sleeve 9 at the position, close to the crimping terminal 8, of the cable end of the coil 6;

and 7, as shown in fig. 10, placing the magnetic pole structure into a glue pouring mold 11, placing the glue pouring mold into a vacuum box 13, and performing vacuum glue pouring, wherein the glue pouring port 12 is located at the bottom of the glue pouring mold 11. In this embodiment, the product is encapsulated by epoxy resin glue, so that the coil 6 and the wiring terminal 7 are fixed, the mechanical strength in the encapsulation area is increased, and the insulating and moisture-proof effects are achieved. After the glue filling, the glue filling mould is placed in a constant temperature box for solidification, and solidification is carried out by stages according to the solidification requirement of the epoxy resin glue: 6h, 80-2 h, 90-2 h, 100-8 h and 130 ℃, cooling and demoulding after solidification is finished.

And 8, opening the mold, checking the appearance of the magnetic pole, trimming the part with burrs, and measuring whether the resistance of the coil is consistent with that before packaging.

The utility model discloses the innovation point lies in:

1. the winding is carried out by using the aluminum enameled wire, so that the independent control requirement on the insulating film is saved, the folding condition after the aluminum film and the insulating film are changed does not exist, the cost and the winding process difficulty are greatly reduced, and the consistency and the reliability of the coil manufacture are improved;

2. a heat-shrinkable ribbon is placed in a rectangular groove on the periphery of the iron core, so that the space is optimally utilized, the groove fullness rate is increased, the ampere-turn number is increased, and the performance of the brake is improved;

3. after the coil is wound, the thermal shrinkage band is welded by hot melting, and the welding interface is moved into the rectangular groove of the iron core, so that the space is optimally utilized, and the fixing strength of the thermal shrinkage band is increased. Meanwhile, the cracking caused by the heating of the welding interface of the thermal shrinkage binding tape during packaging is avoided, and the consistency and reliability of the product are improved.

4. The coil is heated and fastened by heating the heat-shrinkable binding tape, so that the coil without the framework is not loose.

5. The optimized method reduces the welding position from 4 to 2 and increases the welding strength and the welding reliability by crimping a metal material (such as copper) which is easy to weld with copper on an enameled wire and then directly welding the enameled wire with a binding post. The rectangular interface of binding post bottom is favorable to increasing welding strength, and the peripheral spline groove of binding post is favorable to increasing the connection and the joint of binding post and encapsulated layer, increases the mechanical strength of binding post, improves maintenance convenience and product uniformity.

6. And the epoxy resin is used for vacuum packaging, so that the air gap content in the product is greatly reduced, and the heat-conducting property and the insulating property of the final product are improved.

In addition to the above embodiments, the present invention may have other embodiments. All the technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope claimed by the present invention.

Claims (10)

1. A magnetic pole structure comprising:

an iron core (5) for conducting the magnetic circuit and transmitting the braking force,

the insulating layer (3) is wrapped on the periphery of the iron core (5) and used for isolating the coil (6) from the iron core (5);

the coil (6) is wound on the periphery of the insulating layer (3) by adopting an enameled wire and is used for generating magnetomotive force after being electrified;

the supporting layer (2) is arranged on the periphery of the coil and used for improving the packaging strength;

the fixing bandage (4) is used for tightening the coil (6) and fixing the coil (6), the insulating layer (3) and the supporting layer (2) together and keeping the coil, the insulating layer and the supporting layer at the periphery of the iron core (5);

the wiring terminal (7) is arranged in the packaging layer (1) on one side and used for leading out an incoming and outgoing wire of the coil (6) and electrifying the coil;

the packaging layer (1) is wrapped outside the magnetic pole structure and used for sealing the coil (6) and fastening the coil outside the iron core;

the method is characterized in that: the periphery of the iron core (5) is provided with a plurality of grooves (51) in the axial direction at intervals, and the fixing bandage (4) is limited in the grooves (51) of the iron core (5) by the insulating layer (3).

2. The magnetic pole structure of claim 1, wherein: the cross section of the groove (51) is rectangular or semicircular.

3. The magnetic pole structure of claim 1, wherein: the fixing ribbon (4) is a thermal shrinkage ribbon, and welded welding interfaces (41) are positioned on the outer side or two sides of the coil or the inner side of the coil is embedded into a groove (51) of the iron core (5).

4. The magnetic pole structure of claim 1, wherein: the bottom of the binding post (7) is provided with a rectangular groove (71), the crimping terminal (8) is partially clamped into the rectangular groove (71) and is fixed by welding, and the end part of the coil (6) is electrically connected with the crimping terminal (8) and is fixed by crimping.

5. The pole structure of claim 4, wherein: the periphery of the cylinder of the binding post (7) is provided with at least one spline groove (72) which is mutually embedded and contacted with the packaging layer (1).

6. The magnetic pole structure of claim 1, wherein: the supporting layer (2) is a glass fiber net; the insulating layer (3) is an insulating adhesive tape.

7. The magnetic pole structure of claim 1, wherein: and the cable end part of the coil (6) close to the crimping terminal (8) is wrapped with an insulating sleeve (9).

8. The magnetic pole structure of claim 1, wherein: the packaging layer (1) is an epoxy resin packaging layer.

9. The magnetic pole structure of claim 1, wherein: the enameled wire is an aluminum enameled wire.

10. Linear eddy current brake device for magnetic levitation vehicles, characterized in that: having a magnetic pole structure as claimed in any of claims 1 to 9.

Images