Contactor

Abstract

The invention discloses a contactor with an electromagnet design. The contactor comprises a shell; the static iron core is fixed to the shell; the coil at least surrounds one part of the static iron core; the movable iron core can move towards or away from the static iron core; wherein the movable iron core comprises a main body part and an extension part extending from the main body part, the main body part and the extension part partially surround to form a cavity, when the contactor is in a closed state, the static iron core is located in the cavity, and the main body surface of the main body part is attached to the first surface of the static iron core.

Description

Technical Field

[0001] The present invention relates to a contactor, and more particularly to a direct current contactor. Background Art

[0002] The contactor realizes the contact or separation of the moving contact and the static contact through the movement of the moving iron core, thereby realizing the closing or disconnection of the circuit. Specifically, when the circuit needs to be closed, the coil is energized so that the static iron core attracts the moving iron core to move toward the static iron core until the moving iron core and the static iron core fit together, at which time the moving contact and the static contact are in contact, thus realizing the closing of the circuit; when the circuit needs to be disconnected, the coil is de-energized so that the static iron core no longer attracts the moving iron core, and the moving iron core moves in a direction away from the static iron core under the action of the restoring force, thereby realizing the disconnection of the circuit.

[0003] As DC circuits are increasingly widely used in new energy vehicles, photovoltaic power generation and other fields, DC contactors for DC circuits are also widely used. For DC circuits, an arc will be generated when the circuit is disconnected, and the arc is difficult to extinguish, so that when the circuit is disconnected, the static contact and the moving contact need to be separated by a sufficient distance to extinguish the arc, which requires the moving iron core to have a large stroke. However, when the stroke of the moving iron core is large, the attraction between the moving iron core and the static iron core is relatively small when the coil is energized, which makes the closing performance of the contactor worse.

[0004] Therefore, it is desired to provide a contactor that can maintain a large attraction force between the moving iron core and the stationary iron core while satisfying a large stroke of the moving iron core. Summary of the invention

[0005] According to one aspect of the present invention, a contactor is proposed, comprising: a shell; a stationary iron core fixed to the shell; a coil arranged around at least a portion of the stationary iron core; a moving iron core capable of moving toward or away from the stationary iron core; wherein the moving iron core comprises a main body portion and an extension portion extending from the main body portion, the main body portion and the extension portion partially surround a cavity, and when the contactor is in a closed state, the stationary iron core is in the cavity, and the main surface of the main body portion is in contact with the first surface of the stationary iron core.

[0006] According to this scheme, by arranging the extension part, the air gap between the moving iron core and the stationary iron core is reduced, thereby increasing the attraction between the moving iron core and the stationary iron core, so that even if the stroke of the moving iron core is large, the attraction between the moving iron core and the stationary iron core can still be maintained at a high level.

[0007] In some aspects, the inner surface of the extension portion can be perpendicular to the main surface of the main body portion.

[0008] In some embodiments, the static iron core has a second surface perpendicular to the first surface, and when the contactor is in a closed state, a gap between the inner surface of the extension portion and the second surface of the static iron core may be less than 1 mm.

[0009] According to this solution, when the contactor is in a closed state, the air gap between the extended portion of the moving iron core and the stationary iron core is small, so that the attraction between the stationary iron core and the moving iron core is large, making the closed state of the circuit more stable.

[0010] In some aspects, the outer surface of the extension portion may be arranged obliquely relative to the main surface of the main body portion.

[0011] According to this solution, by tilting the outer surface of the extended portion of the moving iron core, the attraction force between the stationary iron core and the moving iron core is further increased, thereby improving the closing performance of the contactor.

[0012] In some aspects, an outer surface of the extension portion may be inclined outwardly in a direction toward the static iron core.

[0013] In some aspects, the inner surface of the extension portion may be arranged obliquely relative to the main surface of the main body portion.

[0014] In some aspects, the inner surface of the extension portion may be inclined inwardly in a direction toward the static iron core.

[0015] In some aspects, the main body portion and the extension portion may be integrally formed.

[0016] In some solutions, when the contactor is in the open state, an end of the extension portion close to the static iron core is flush with the first surface of the static iron core.

[0017] According to this solution, when the contactor is in the disconnected state, the air gap between the end of the extended part of the moving iron core close to the static iron core and the static iron core is very small, which further increases the initial attraction when the contactor starts to close and improves the closing performance of the contactor.

[0018] In some aspects, the contactor is a DC contactor.

[0019] According to this solution, the contactor is used in a DC circuit, which requires a larger distance between the moving contact and the stationary contact to make the arc easier to extinguish, so that the moving iron core needs a longer stroke. The contactor of the present invention can still maintain a large attraction between the moving iron core and the stationary iron core when the moving iron core has a longer stroke, thereby avoiding a decrease in the closing performance of the contactor due to the longer stroke of the moving iron core. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a contactor according to an embodiment of the present invention is shown;

[0021] Figure 2 A partial three-dimensional schematic diagram of a contactor according to a first embodiment of the present invention is shown;

[0022] Figure 3 The variation curve of the attraction force between the moving iron core and the stationary iron core of the contactor according to the embodiment of the present invention is shown;

[0023] Figure 4 A partial cross-sectional schematic diagram of a contactor according to a first embodiment of the present invention is shown;

[0024] Figure 5 A partial cross-sectional schematic diagram of a contactor according to a second embodiment of the present invention is shown;

[0025] Figure 6 A partial cross-sectional schematic diagram of a contactor according to a third embodiment of the present invention is shown;

[0026] Figure numerals: 100 contactor, 110 static iron core, 112 first surface, 114 second surface, 120 moving iron core, 122 main body, 123 main body surface, 124 extension part, 126 inner surface, 127 outer surface, 128 cavity, 130 coil, 140 static contact, 150 moving contact. DETAILED DESCRIPTION

[0027] In order to make the purpose, scheme and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the drawings of the specific embodiments of the present invention. Unless otherwise specified, the terms used herein have the usual meanings in the art. The same reference numerals in the drawings represent the same components.

[0028] Figure 1A schematic diagram of a contactor 100 according to an embodiment of the present invention is shown, and the contactor 100 mainly includes a stationary iron core 110 fixed to a housing, a moving iron core 120 capable of moving toward or away from the stationary iron core 110, a coil 130 arranged at least around a portion of the stationary iron core 110, a stationary contact 140, and a moving contact 150. When the circuit is in an open state, the stationary contact 140 is separated from the moving contact 150. At this time, if the circuit needs to be closed, the coil 130 is energized so that the stationary iron core 110 is magnetized, so that the moving iron core 120 is attracted by the stationary iron core 110 and moves toward the stationary iron core 110, thereby driving the moving contact 150 to move toward the stationary contact 140, and finally the moving contact 150 moves to contact with the stationary contact 140, so that the circuit is closed. When the circuit is in a closed state, the static contact 140 is in contact with the moving contact 150. If the circuit needs to be disconnected at this time, the coil 130 is de-energized to demagnetize the static iron core 110, so that the moving iron core 120 is no longer attracted by the static iron core 110 and moves away from the static iron core 110 under the action of a restoring force (for example, the elastic force of a spring), thereby driving the moving contact 150 to move away from the static contact 140, so that the moving contact 150 is separated from the static contact 140, and the circuit is disconnected.

[0029] As DC circuits are increasingly widely used in new energy vehicles, photovoltaic power generation and other fields, DC contactors 100 for DC circuits also have a wide range of application needs. For DC contactors 100, if the separation distance between the moving contact 150 and the static contact 140 is not large enough in the circuit disconnected state, the circuit may be adversely affected by an electric arc. In order to reduce the adverse effects caused by possible electric arcs, the distance between the moving contact 150 and the static contact 140 needs to be large enough in the circuit disconnected state, which results in a large stroke of the moving iron core 120. In the prior art, when the stroke of the moving iron core 120 is large, the distance between the moving iron core 120 and the static iron core 110 is large, so that the attraction between the moving iron core 120 and the static iron core 110 is small, which reduces the closing performance of the contactor 100.

[0030] The present invention provides a contactor 100, which can ensure that the attraction between the moving iron core 120 and the stationary iron core 110 can still be maintained at a high level even if the stroke of the moving iron core 120 is large. Figure 2As shown, the moving iron core 120 includes a main body portion 122 and an extension portion 124 extending from the main body portion 122. The main body portion 122 and the extension portion 124 partially surround and form a cavity 128. When the contactor 100 is in a closed state, the stationary iron core 110 enters the cavity 128, and the main body surface 123 of the main body portion 122 is in contact with the first surface 112 of the stationary iron core 110. By arranging the extension portion 124, the air gap between the moving iron core 120 and the stationary iron core 110 is reduced, thereby increasing the attraction between the moving iron core 120 and the stationary iron core 110, so that even if the stroke of the moving iron core 120 is large, the attraction between the moving iron core 120 and the stationary iron core 110 can still be maintained at a high level.

[0031] Figure 3 The change curve of the attraction between the moving iron core 120 and the static iron core 110 of the contactor 100 according to the embodiment of the present invention is shown, wherein the horizontal axis represents the stroke of the moving iron core 120, and the vertical axis represents the attraction between the moving iron core 120 and the static iron core 110. It can be seen that, compared with the contactor of the conventional design, the contactor 100 of the present invention can still maintain a relatively large attraction between the moving iron core 120 and the static iron core 110 when the stroke of the moving iron core 120 is large. For example, when the stroke of the moving iron core 120 is 13mm, the attraction between the moving iron core and the static iron core of the contactor of the conventional design is only 8N, while the attraction between the moving iron core 120 and the static iron core 110 of the contactor 100 of the present invention can be as high as 42N, indicating that the contactor 100 of the present invention makes the attraction between the moving iron core 120 and the static iron core 110 increased by about 5 times compared with the conventional design. The above characteristics ensure that even when the moving iron core 120 has a large stroke, a high attraction force can be maintained between the moving iron core 120 and the stationary iron core 110. As a result, when the moving iron core 120 has a large stroke designed to reduce the impact of the arc, the stationary iron core 110 can still effectively attract the moving iron core 120, so that the closing performance of the contactor 100 will not be reduced due to the large stroke of the moving iron core 120.

[0032] Alternatively, if Figure 4 As shown, the inner surface 126 of the extension portion 124 may be perpendicular to the main surface 123 of the main body portion 122, and the outer surface 127 of the extension portion 124 may be arranged obliquely relative to the main surface 123 of the main body portion 122. Preferably, the outer surface 127 of the extension portion 124 may be inclined outwardly in a direction toward the static iron core 110.

[0033] Alternatively, if Figure 5 As shown, the inner surface 126 and the outer surface 127 of the extension portion 124 may both be perpendicular to the main surface 123 of the main body portion 122 .

[0034] Alternatively, if Figure 6As shown, the outer surface 127 of the extension portion 124 may be perpendicular to the main surface 123 of the main body portion 122, and the inner surface 126 of the extension portion 124 may be arranged obliquely relative to the main surface 123 of the main body portion 122. Preferably, the inner surface 126 of the extension portion 124 may be inclined inwardly in the direction toward the static iron core 110.

[0035] Preferably, when the contactor is in a closed state, the gap between the inner surface 126 of the extension portion 124 and the second surface 114 of the static iron core 110 can be less than 1 mm, wherein the second surface 114 of the static iron core 110 is perpendicular to the first surface 112 of the static iron core 110. When the contactor 100 is in a closed state, the air gap between the extension portion 124 of the moving iron core 120 and the static iron core 110 is small, so that the attraction between the static iron core 110 and the moving iron core 120 is large, making the closed state of the circuit more stable. It should be understood that when the contactor is in a closed state, the gap width between the inner surface 126 of the extension portion 124 and the second surface 114 of the static iron core 110 is only exemplary, and the gap width can also be set to any other suitable distance according to specific application requirements.

[0036] Preferably, when the contactor 100 is in the disconnected state, one end of the extension portion 124 close to the static iron core 110 is flush with the first surface 112 of the static iron core 110. When the contactor 100 is in the disconnected state, the air gap between one end of the extension portion 124 of the moving iron core 120 close to the static iron core 110 and the static iron core 110 is very small, which further increases the initial attraction when the contactor 100 starts to close, and improves the closing performance of the contactor 100.

[0037] This document describes in detail several exemplary embodiments of the present invention with reference to preferred embodiments. However, it will be understood by those skilled in the art that, without departing from the concept of the present invention, various modifications and variations may be made to the above-mentioned specific embodiments, and various technical features and structures proposed in the present invention may also be combined without exceeding the protection scope of the present invention, which is determined by the appended claims.

Claims

1. A contactor, characterized in that: include: case; A static iron core fixed to the housing; A coil arranged around at least a portion of the static iron core; A moving iron core capable of moving toward or away from the stationary iron core; The moving iron core includes a main body part and an extension part extending from the main body part, wherein the main body part and the extension part partially surround a cavity, and when the contactor is in a closed state, the stationary iron core is in the cavity, and the main surface of the main body part is in contact with the first surface of the stationary iron core.

2. The contactor according to claim 1, characterized in that: An inner surface of the extension portion is perpendicular to a main surface of the main body portion.

3. The contactor according to claim 2, characterized in that: An outer surface of the extension portion is arranged obliquely with respect to a main body surface of the main body portion.

4. The contactor according to claim 3, characterized in that: An outer surface of the extending portion is inclined outward in a direction toward the static iron core.

5. The contactor according to claim 2, characterized in that: The static iron core has a second surface perpendicular to the first surface, and when the contactor is in a closed state, a gap is provided between the inner surface of the extending portion and the second surface of the static iron core.

6. The contactor according to claim 1, characterized in that: An inner surface of the extension portion is arranged obliquely relative to a main body surface of the main body portion.

7. The contactor according to claim 6, characterized in that: An inner surface of the extending portion is inclined inwardly in a direction toward the static iron core.

8. The contactor according to any one of claims 1 to 7, characterized in that: The main body portion and the extension portion are integrally formed.

9. The contactor according to any one of claims 1 to 7, characterized in that: When the contactor is in an off state, one end of the extending portion close to the static iron core is flush with the first surface of the static iron core.

10. The contactor according to any one of claims 1 to 7, characterized in that: The contactor is a DC contactor.

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