An electromagnetic contactor

Abstract

The invention discloses an electromagnetic contactor, comprising an electromagnetic contactor body; a contact assembly, located in the electromagnetic contactor body, comprising a moving contact and a static contact; an arc extinguishing assembly; a contact pull-in assembly, comprising a first coil, a second coil and a moving assembly, the moving assembly comprising a moving iron core, a swing arm, a compression spring and a contact fixing seat, the moving iron core is located above the first coil, the lower end of the moving iron core enters the middle of the first coil, the upper end is hinged with one end of the swing arm, the other end of the swing arm is hinged with the electromagnetic contactor body, one end of the contact fixing seat is fixedly arranged on the swing arm, and the moving contact is fixedly arranged on the other end of the swing arm; when the first coil is energized to move the moving iron core downward, the swing arm and the contact fixing seat can be driven to swing, so that the moving contact hits the static contact; a coil pull-in control assembly, comprising a first travel switch; a pressing block is fixedly arranged on the moving iron core, and after the moving iron core moves downward by a set distance, the pressing block squeezes the contact of the first travel switch, so that the second coil is connected in series with the loop of the first coil.

Description

Technical Field

[0001] The invention belongs to the technical field of contactors, and in particular relates to an electromagnetic contactor. Background Art

[0002] The converter installed in the traction main circuit of electric locomotives and other locomotives equipped with electric transmission devices. The function of the traction converter is to convert the electrical energy between DC and AC, and to control and regulate various traction motors, thereby controlling the operation of the locomotive.

[0003] In order to realize the opening / closing of the auxiliary converter input terminal and the secondary auxiliary winding of the main transformer, it is necessary to install an electromagnetic contactor in the traction auxiliary converter of the power concentrated EMU; although the existing electromagnetic contactor can realize the opening / closing of the auxiliary converter input terminal and the secondary auxiliary winding of the main transformer, due to the high voltage and large current between the converter input terminal and the secondary auxiliary winding of the main transformer, a strong arc will be generated when the electromagnetic contactor switches from closing to opening. The existing technology often uses an arc extinguishing hood to extinguish the arc, but the arc extinguishing effect is not good, which often causes the contacts and internal structure of the electromagnetic contactor to be burned by the arc, resulting in damage to the electromagnetic contactor; in addition, when the electromagnetic contactor is closed, it is necessary to use a coil with a larger current and a higher attraction to start the moving contact and contact the static contact, but after starting, the power of the coil is The requirements for rate and attraction will be reduced, so only a coil with low power can maintain continuous contact between the moving contact and the static contact under long-term energized operation. In order to solve this problem, the prior art uses a starting coil for starting, and after starting, the electronic module controls the series connection of a resistor in the loop of the starting coil to reduce the current of the starting coil to solve the above problem. However, it has the problems of high heating of the resistor and low stability of the electronic module in a high-voltage use environment. In addition, after the arc extinguishing hood has been used for a period of time, the arc extinguishing hood will be more obviously damaged in places where the arc is more concentrated, thereby affecting the arc extinguishing effect. However, at this time, other components inside the electromagnetic contactor are still intact and have not reached their service life. If the entire machine is directly replaced, the cost will be too high, but there will be risks in continuing to use it. Summary of the invention

[0004] The purpose of the present invention is to provide an electromagnetic contactor, which is intended to solve the technical problems existing in the background technology.

[0005] To solve the above technical problems, the purpose of the present invention is achieved as follows:

[0006] An electromagnetic contactor comprises an electromagnetic contactor body; a contact assembly located in the electromagnetic contactor body and comprising a moving contact and a static contact; and

[0007] A contact pull-in assembly comprises a first coil, a second coil and a moving assembly, wherein the moving assembly comprises a moving iron core, a swing arm, a compression spring and a contact fixing seat, wherein the moving iron core is located above the first coil, the lower end of the moving iron core enters the middle of the first coil, the upper end is hinged to one end of the swing arm, the other end of the swing arm is hinged to the electromagnetic contactor body, one end of the contact fixing seat is fixed to the swing arm, and the moving contact is fixed to the other end of the swing arm; when the first coil is energized to move the moving iron core downward, the swing arm and the contact fixing seat can be driven to swing, so that the moving contact hits the static contact; the compression spring is sleeved outside the moving iron core, the lower end of the compression spring contacts the upper end of the first coil, and the upper end contacts the moving iron core;

[0008] The coil pull-in control assembly comprises a first travel switch; a pressing block is fixedly arranged on the moving iron core, and after the moving iron core moves downward by a set distance, the pressing block presses the contact of the first travel switch to connect the second coil in series with the loop of the first coil;

[0009] An arc extinguishing assembly comprises an arc extinguishing cover, and the arc extinguishing cover is arranged outside the moving contact and the static contact.

[0010] On the basis of the above scheme and as a preferred scheme of the above scheme: it also includes a second travel switch, the first travel switch and the second travel switch are symmetrically arranged on both sides of the moving iron core, and the pressure blocks are symmetrically arranged with two corresponding to the first travel switch and the second travel switch respectively.

[0011] On the basis of the above scheme and as a preferred scheme of the above scheme: it also includes a moving contact lead-out terminal fixedly arranged on the electromagnetic contactor body, and the moving contact is connected to the moving contact lead-out terminal through a flexible conductive material.

[0012] On the basis of the above solution and as a preferred solution of the above solution: the first coil and the second coil are separated and arranged side by side.

[0013] On the basis of the above scheme and as a preferred scheme of the above scheme: the normally closed contact of the first travel switch is connected in parallel with the second coil and then connected in series in the loop of the first coil.

[0014] On the basis of the above scheme and as a preferred scheme of the above scheme: the arc extinguishing assembly also includes an arc striking assembly, the arc striking assembly includes an arc striking coil and magnetic flux plates symmetrically arranged on both sides of the contact assembly, a magnetic conductive column is passed through the middle of the arc striking coil, the magnetic flux plates are respectively in contact with the two end surfaces of the magnetic conductive column, and the magnetic flux plates are located in the electromagnetic contactor body and are attached to the outer surface of the arc extinguishing cover.

[0015] On the basis of the above scheme and as a preferred scheme of the above scheme: it also includes a first arc-striking plate and a second arc-striking plate; the first arc-striking plate is located above the moving contact, with the front end close to the moving contact and the rear end extending into the arc-extinguishing cover; the second arc-striking plate is located above the static contact, with the front end close to the static contact and the rear end extending into the arc-extinguishing cover.

[0016] On the basis of the above solution and as a preferred solution of the above solution: the arc extinguishing cover is detachably fixed on the electromagnetic contactor body through a quick-release assembly.

[0017] On the basis of the above scheme and as a preferred scheme of the above scheme: the quick-release assembly includes a clamping part fixed to the electromagnetic contactor body, and a clamping piece connected to the arc-extinguishing cover, the clamping piece has a clamping part bent or protruding toward the clamping part, and after the arc-extinguishing cover is pressed against the upper end surface of the electromagnetic contactor body, the clamping part is clamped with the clamping part; the clamping part is provided with a handle on the side away from the clamping part, and an external force is applied to the handle to separate the clamping part from the clamping part.

[0018] On the basis of the above scheme and as a preferred scheme of the above scheme: a spring contacts the side of the end of the clamping piece away from the clamping part, a support column is provided between the spring and the clamping part, the clamping piece rotates around the support column, and the spring always keeps applying a trend force to the clamping piece, and the trend force makes the clamping part clamped to the clamping part.

[0019] Compared with the prior art, the present invention has the following outstanding and beneficial technical effects: 1. The start coil and the holding coil of the present application are separately arranged, which is beneficial to the heat dissipation of the coil.

[0020] 2. The normally closed contact of the first travel switch is connected in parallel with the second coil (holding coil) and then connected in series in the loop of the first coil. Then, at startup, the normally closed contact of the first travel switch will short-circuit the second coil, so that the voltage of the starting power supply is directly loaded on both ends of the first coil. After the moving iron core of the first coil (starting coil) is sucked down to make the moving contact contact with the static contact, the pressure block will press down the contact at the beginning of the first stroke to separate the normally closed contact, so that the second coil is connected in series in the loop of the first coil, realizing the role of voltage reduction and current limiting, thereby reducing the power of the first coil and reducing its heat generation; and adopts a mechanical switching method with high reliability, low cost, and not easily interfered with, which is more conducive to long-term stable operation in a high-voltage environment.

[0021] 3. The arc extinguishing hood is detachably fixed on the electromagnetic contactor body through a quick-release assembly. Therefore, when the arc extinguishing hood is damaged, the electromagnetic contactor can continue to operate well by quickly replacing the arc extinguishing hood, avoiding the problem of the existing electromagnetic contactor arc extinguishing hood integral design, which is not conducive to maintenance, and the overall replacement of the arc extinguishing hood when there is a problem leads to high maintenance costs.

[0022] 4. The magnetic flux plate of the arc striking assembly is arranged in the main body of the electromagnetic contactor and is located on both sides of the arc extinguishing cover. It adopts a position closer to the moving and static contacts, and the area of ​​the magnetic flux plate is increased, which is more conducive to introducing the arc generated by the moving and static contacts into the arc extinguishing cover, so that the arc can be extinguished quickly, avoiding the problem that the arc extinguishing effect of the electromagnetic contactor in the prior art is poor, resulting in long-term arcing and damaging the electromagnetic contactor and other auxiliary circuits.

[0023] 5. The addition of the first arc-starting plate and the second arc-starting plate further enhances the arc-starting effect, thereby making the arc extinguishing speed faster. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a three-dimensional schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is another three-dimensional schematic diagram of the overall structure of the present invention;

[0026] Figure 3 It is the overall structural front view of the present invention;

[0027] Figure 4 It is a schematic diagram of the internal structure of the present invention;

[0028] Figure 5 It is a schematic diagram of the coil attraction control principle of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of this application clearer, the technical solution in the embodiment will be clearly and completely described below in conjunction with the drawings in the embodiment. Obviously, the described embodiment is only a part of the embodiment of this application, not all embodiments. Based on the given embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0030] In the description of the present application, it should be understood that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] In the description of this application, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0032] Combination Figure 1-4 An electromagnetic contactor includes an electromagnetic contactor body 10, including a base 11, a base side plate 12 and a body side plate 13; a contact assembly 20, located in the electromagnetic contactor body 10, including a moving contact 22 and a static contact 21; and also includes a moving contact lead-out terminal 24 and a static contact lead-out terminal 23 fixed on the electromagnetic contactor body 10, wherein the moving contact 22 is connected to the moving contact 22 lead-out terminal through a flexible conductive material 25. Preferably, the flexible conductive material is a braided copper belt, one end of the braided copper belt is connected to the moving contact, and the other end is connected to the moving contact lead-out terminal 24.

[0033] Also includes

[0034] The contact pull-in assembly 30 includes a first coil 31, a second coil 32 and a moving assembly 33. The moving assembly 33 includes a moving iron core 331, a swing arm 332, a compression spring 334 and a contact fixing seat 336. The first coil 31 and the second coil 32 are fixedly arranged on the base 11. The base side plate 12 and the main body side plate 13 shield the contact assembly 20 and the contact pull-in assembly 30. The moving iron core 331 is located above the first coil 31. The lower end of the moving iron core 331 enters the middle of the first coil 31, and the upper end is hinged to one end of the swing arm 332. The other end of the swing arm 332 is hinged to the electromagnetic contactor body 10 through a hinge shaft 333. One end of the contact fixing seat 336 is fixed It is arranged on the swing arm 332, and the moving contact 22 is fixedly arranged at the other end of the swing arm 332; when the first coil 31 is energized to make the moving iron core 331 move downward, the swing arm 332 and the contact fixing seat 336 can be driven to swing, so that the moving contact 22 hits the static contact 21; the compression spring 334 is sleeved outside the moving iron core 331, and the lower end of the compression spring 334 contacts the upper end of the first coil 31, and the upper end contacts a spring seat fixed on the moving iron core 331, so that after the first coil is de-energized, the moving iron core 331 moves upward under the action of the compression spring 334, thereby pushing up the swing arm, so that the moving contact 22 is separated from the static contact 21, thereby realizing the switching between opening and closing of the electromagnetic contactor.

[0035] The coil pull-in control assembly 50 includes a first travel switch 51; a pressing block 335 is fixedly mounted on the moving iron core 331. After the moving iron core 331 moves downward by a set distance, the pressing block 335 squeezes the contact of the first travel switch 51, and connects the second coil 32 in series with the loop of the first coil 31. Specifically, in combination with Figure 5The first coil 31 and the second coil 32 are separated and arranged side by side, which is beneficial to the heat dissipation of the coils; the normally closed contact SQ1 of the first travel switch is connected in parallel with the second coil 32 and then connected in series in the loop of the first coil 31. Then, at startup, the normally closed contact of the first travel switch will short-circuit the second coil, so that the voltage of the starting power supply is directly loaded on both ends of the first coil. After the moving iron core of the first coil (starting coil) is sucked down to make the moving contact contact with the static contact, the pressure block will press down the contact at the beginning of the first stroke to separate the normally closed contact, so that the second coil is connected in series in the loop of the first coil, realizing the function of voltage reduction and current limiting, thereby reducing the power of the first coil and reducing its heat generation; and adopting a mechanical switching method, it has high reliability, low cost, is not easily interfered with, and is more conducive to long-term stable operation in a high-voltage environment.

[0036] It is further preferred that a second travel switch 52 is further included, wherein the first travel switch 51 and the second travel switch 52 are symmetrically arranged on both sides of the moving iron core 331, and two pressing blocks 335 are symmetrically arranged and correspond to the first travel switch 51 and the second travel switch 52 respectively; specifically, during the downward movement of the moving iron core 331, the two pressing blocks 335 can simultaneously contact with the contact 511 of the first travel switch 51 and the contact 521 of the second travel switch 52 and press the contacts downward, thereby connecting or disconnecting the contacts inside the first travel switch 51 and the second travel switch 52. It should be noted that the second travel switch 52 is used to connect with the communication interface 53, and after the moving contact and the static contact are closed to the specified position, the contact inside the second travel switch 52 is triggered, thereby satisfying the signal transmission, and then the signal can be fed back to the external control system through the communication interface 53.

[0037] The arc extinguishing assembly 40 includes an arc extinguishing cover 41, and the arc extinguishing cover 41 is arranged outside the moving contact 22 and the static contact 21. The arc extinguishing assembly 40 also includes an arc striking assembly 42, and the arc striking assembly 42 includes an arc striking coil 421 and a magnetic flux plate 422 symmetrically arranged on both sides of the contact assembly 20. A magnetic conductive column 4211 is penetrated in the middle of the arc striking coil 421, and the magnetic flux plate 422 is respectively in contact with the two end surfaces of the magnetic conductive column 4211. The magnetic flux plate 422 is located in the electromagnetic contactor body 10 and is attached to the outer surface of the arc extinguishing cover 41. Preferably, the wire diameter of the arc striking coil 421 is increased from φ1.8 to φ2.0 to increase the magnetic flux, and the magnetic flux plate is further extended to the top and bottom of the contact assembly, for example, it is increased to 50mm on the basis of the existing magnetic flux plate, so that the arc is more easily led into the arc extinguishing cover, solving the problem that the existing electromagnetic contactor cannot normally draw an arc or the arc drawing is unstable.

[0038] More preferably, a first arc-starting plate 451 and a second arc-starting plate 452 are further included; the first arc-starting plate 451 is located above the moving contact 22, and the front end is close to the moving contact 22, and the rear end extends into the arc-extinguishing cover 41; the second arc-starting plate 452 is located above the stationary contact 21, and the front end is close to the stationary contact 21, and the rear end extends into the arc-extinguishing cover 41. The addition of the first arc-starting plate and the second arc-starting plate further enhances the arc-starting effect, thereby making the arc-extinguishing speed faster.

[0039] After the arc extinguishing hood has been used for a period of time, there will be obvious damage to the arc extinguishing hood where the arc is more concentrated, thereby affecting the arc extinguishing effect. However, at this time, other components inside the electromagnetic contactor are still intact and have not reached their service life. In this case, if the entire machine is replaced directly, the cost will be too high, but there will be risks in continuing to use it. For this reason, the present application further prefers that the arc extinguishing hood 41 is detachably fixed to the electromagnetic contactor body 10 through a quick-release assembly 46. Specifically, the quick-release assembly 46 includes a clamping portion 462 fixed to the electromagnetic contactor body 10, and a clamping piece 461 connected to the arc-extinguishing cover 41, the clamping piece 461 has a clamping portion 4611 bent or protruding toward the clamping portion 462, and after the arc-extinguishing cover 41 is pressed against the upper end surface of the electromagnetic contactor body 10, the clamping portion 4611 is clamped to the clamping portion 462; the clamping portion 4611 is provided with a handle 46111 on the side away from the clamping portion 462, and an external force is applied to the handle 46111 to separate the clamping portion 4611 from the clamping portion 462. A spring 464 contacts the side of the clamping piece away from the end 4612 of the clamping part, a support column 463 is provided between the spring 464 and the clamping part 462, the clamping piece 461 rotates around the support column 463, and the spring 464 always keeps applying a tendency force to the clamping piece 461, and the tendency force clamps the clamping part 4611 to the clamping part 462. The arc extinguishing cover 41 is detachably fixed to the electromagnetic contactor body through a quick release assembly 46, so when the arc extinguishing cover 41 is damaged, the electromagnetic contactor can continue to operate well by quickly replacing the arc extinguishing cover, avoiding the problem of the existing electromagnetic contactor arc extinguishing cover integral design, which is not conducive to maintenance, and the overall replacement of the arc extinguishing cover when there is a problem leads to high maintenance costs.

[0040] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An electromagnetic contactor, comprising an electromagnetic contactor body; a contact assembly, located in the electromagnetic contactor body, comprising a moving contact and a static contact; characterized in that: Also includes A contact pull-in assembly comprises a first coil, a second coil and a moving assembly, wherein the moving assembly comprises a moving iron core, a swing arm, a compression spring and a contact fixing seat, wherein the moving iron core is located above the first coil, the lower end of the moving iron core enters the middle of the first coil, the upper end is hinged to one end of the swing arm, the other end of the swing arm is hinged to the electromagnetic contactor body, one end of the contact fixing seat is fixed to the swing arm, and the moving contact is fixed to the other end of the swing arm; when the first coil is energized to move the moving iron core downward, the swing arm and the contact fixing seat can be driven to swing, so that the moving contact hits the static contact; the compression spring is sleeved outside the moving iron core, the lower end of the compression spring contacts the upper end of the first coil, and the upper end contacts the moving iron core; The coil pull-in control assembly comprises a first travel switch; a pressing block is fixedly arranged on the moving iron core, and after the moving iron core moves downward by a set distance, the pressing block presses the contact of the first travel switch to connect the second coil in series with the loop of the first coil; An arc extinguishing assembly, the arc extinguishing assembly comprising an arc extinguishing cover, the arc extinguishing cover being arranged outside the moving contact and the static contact; It also includes a second travel switch, wherein the first travel switch and the second travel switch are symmetrically arranged on both sides of the moving iron core, and two pressing blocks are symmetrically arranged and correspond to the first travel switch and the second travel switch respectively; The arc extinguishing assembly also includes an arc striking assembly, which includes an arc striking coil and magnetic flux plates symmetrically arranged on both sides of the contact assembly, a magnetic conductive column is passed through the middle of the arc striking coil, and the magnetic flux plates are respectively in contact with the two end surfaces of the magnetic conductive column, the magnetic flux plate is located in the electromagnetic contactor body and is attached to the outer surface of the arc extinguishing cover, and also includes a first arc striking plate and a second arc striking plate; the first arc striking plate is located above the moving contact, and the front end is close to the moving contact, and the rear end extends into the arc extinguishing cover; the second arc striking plate is located above the static contact, and the front end is close to the static contact, and the rear end extends into the arc extinguishing cover.

2. An electromagnetic contactor according to claim 1, characterized in that: It also includes a moving contact lead-out terminal fixedly arranged on the electromagnetic contactor body, and the moving contact is connected to the moving contact lead-out terminal through a flexible conductive material.

3. The electromagnetic contactor according to claim 1, characterized in that: The first coil and the second coil are separate and arranged side by side.

4. The electromagnetic contactor according to claim 1, characterized in that: The normally closed contact of the first travel switch is connected in parallel with the second coil and then connected in series in the loop of the first coil.

5. The electromagnetic contactor according to claim 1, characterized in that: The arc extinguishing cover is detachably fixed on the electromagnetic contactor body through a quick-release assembly.

6. An electromagnetic contactor according to claim 5, characterized in that: The quick-release assembly includes a clamping portion fixed to the electromagnetic contactor body, and a clamping piece connected to the arc-extinguishing cover, wherein the clamping piece has a clamping portion bent or protruding toward the clamping portion, and after the arc-extinguishing cover is pressed against the upper end surface of the electromagnetic contactor body, the clamping portion is clamped to the clamping portion; the clamping portion is provided with a handle on the side away from the clamping portion, and an external force is applied to the handle to separate the clamping portion from the clamping portion.

7. An electromagnetic contactor according to claim 6, characterized in that: A spring contacts the side surface of one end of the clamping piece away from the clamping part, a support column is provided between the spring and the clamping part, the clamping piece rotates around the support column, and the spring always keeps applying a tendency force to the clamping piece, and the tendency force clamps the clamping part to the clamping part.

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