Electromagnetic release and circuit breaker

Abstract

The electromagnetic release comprises a magnet yoke, a permanent magnet, an iron core, a magnetic conductive end cover, a coil framework and a coil arranged on the coil framework in a sleeving mode, a blocking piece is arranged between a first attraction face of the iron core and the magnetic conductive end cover, and when the electromagnetic release is in an opening state, the iron core attracts the magnetic conductive end cover under the action of opening driving force. The iron core drives the contact mechanism to open and provides opening holding force for the contact mechanism. The first attraction face of the iron core is blocked by the blocking piece, and a magnetic conduction gap used for weakening the opening holding force is formed between the first attraction face of the iron core and the magnetic conduction end cover. The circuit breaker comprises a control system, a contact mechanism and an electromagnetic release. According to the electromagnetic release and the circuit breaker, the blocking piece is blocked between the first attraction surface of the iron core and the magnetic conduction end cover, so that a magnetic conduction gap is reserved when the first attraction surface of the iron core and the magnetic conduction end cover attract each other, the holding force of the electromagnetic release in an opening state is reduced, and the power required by the circuit breaker in a closing state can be reduced.

Description

Technical Field

[0001] The utility model relates to the field of low-voltage electrical appliances, in particular to an electromagnetic release and a circuit breaker. Background Art

[0002] Most existing bidirectional electromagnetic releases are used in circuit breakers. Because there is final pressure between the moving and static contacts when the circuit breaker is closed (switched on), the suction force during closing and opening is inconsistent, with the closing force being greater than the opening force. As a result, the operator requires a greater closing force when manually closing the circuit breaker. At the same time, the power required to close the circuit breaker during automatic closing is greater than the power required to open the circuit breaker. Utility Model Content

[0003] The purpose of the present utility model is to overcome at least one defect of the prior art and provide an electromagnetic release and a circuit breaker.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] The electromagnetic release comprises a magnetic yoke, a permanent magnet, an iron core, a magnetic end cover, a coil frame and a coil sleeved on the coil frame. The magnetic yoke has an engaging side wall opposite to the magnetic end cover, the permanent magnet is located between the magnetic end cover and the engaging side wall, the iron core is movably arranged in the axial hole of the coil frame and is located between the magnetic end cover and the engaging side wall, the two ends of the iron core are respectively provided with a first engaging surface opposite to the magnetic end cover and a second engaging surface opposite to the engaging side wall, the iron core is driven and cooperated with the contact mechanism, and a blocking member is provided between the first engaging surface of the iron core and the magnetic end cover.

[0006] When the electromagnetic release is in the open state, the iron core is attracted to the magnetic end cover under the action of the opening driving force, and the iron core drives the contact mechanism to open and provides the contact mechanism with an opening holding force.

[0007] The first attraction surface of the iron core is blocked by the blocking member and a magnetic gap is provided between the first attraction surface of the iron core and the magnetic end cover for reducing the opening holding force.

[0008] Optionally, the blocking member is a boss integrally provided on the first attraction surface of the iron core; or, the blocking member is a boss integrally provided on the magnetic end cover.

[0009] Optionally, the blocking member is a straight plate structure made of non-magnetic material, and the blocking member is fixed on the first attraction surface of the iron core or the magnetic end cover.

[0010] Optionally, the magnetic yoke is a U-shaped structure, the magnetic end cover is covered and fixed on the opening of the magnetic yoke and forms an accommodating cavity between the magnetic yoke, the permanent magnet is sleeved on the outer side of the coil frame and is located in the center between the magnetic end cover and the attraction side wall, the iron core is slidably arranged in the axial hole of the coil frame, and the coil frame is installed in the accommodating cavity and is located between the magnetic end cover and the attraction side wall.

[0011] Optionally, the coil includes a first coil and a second coil respectively wound on a coil frame, the first coil and the second coil have the same winding direction, and the first coil and the second coil are arranged in parallel, and the permanent magnet is located between the first coil and the second coil.

[0012] Optionally, the iron core is driven to cooperate with the contact mechanism through a push rod, one end of the push rod passes through the through hole on the attraction side wall and is fixedly connected to the end of the iron core used to engage with the attraction side wall, and the other end of the push rod is used to cooperate with the contact mechanism.

[0013] A circuit breaker includes a control system and a contact mechanism, and also includes any of the above-mentioned electromagnetic releases, wherein the control system applies a forward voltage to the coil of the electromagnetic release to provide a closing driving force for the iron core of the electromagnetic release; and the control system applies a reverse voltage to the coil of the electromagnetic release to provide an opening driving force for the iron core of the electromagnetic release.

[0014] Optionally, the contact mechanism includes a contact support, a moving contact and a contact spring that provides contact pressure for the moving contact. The iron core of the electromagnetic release is driven to cooperate with the contact support of the contact mechanism. One end of the moving contact is rotatably mounted on the contact support via a rotating shaft, and the other end of the moving contact cooperates with the static contact.

[0015] Optionally, the iron core is driven to cooperate with the contact support of the contact mechanism through a push rod, the push rod is fixedly connected to the connecting rod, and the connecting rod is hinged to the contact support through a hinge shaft.

[0016] Optionally, the contact spring is a torsion spring, the contact spring is sleeved on the rotating shaft, one end of the contact spring abuts against the contact support, and the other end of the contact spring abuts against the moving contact.

[0017] The electromagnetic release and circuit breaker of the present invention use a blocking member to block between the first attraction surface of the iron core and the magnetic end cover, so that a magnetic gap is left when the first attraction surface of the iron core and the magnetic end cover are attracted to each other, thereby reducing the holding force of the electromagnetic release in the open state, thereby reducing the power required for closing the circuit breaker.

[0018] In addition, due to the reaction force of the contact spring, the closing holding force is weakened, so that the opening driving force and closing driving force of the circuit breaker are almost the same, and the opening power and closing power can be almost the same. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a partial structural diagram of the circuit breaker in the open state of the utility model;

[0020] Figure 2 This is a schematic diagram of the partial structure of the circuit breaker in the closed state of the utility model;

[0021] Figure 3 This is a schematic structural diagram of an electromagnetic release according to a first embodiment of the present invention;

[0022] Figure 4 This is a cross-sectional view of an electromagnetic release according to a first embodiment of the present invention;

[0023] Figure 5 This is a structural schematic diagram of the electromagnetic release of the first embodiment of the present utility model without the coil skeleton and the coil;

[0024] Figure 6 This is a schematic structural diagram of a coil skeleton, a coil, and a permanent magnet in a first embodiment of the present invention;

[0025] Figure 7 This is a schematic structural diagram of the iron core of the first embodiment of the present utility model;

[0026] Figure 8 This is a cross-sectional view of the electromagnetic release of the second embodiment of the present utility model;

[0027] Figure 9 This is a schematic structural diagram of the magnetic conductive end cover of the second embodiment of the present utility model;

[0028] Figure 10 This is an exploded view of the contact mechanism of the utility model;

[0029] Figure 11 It is an assembly drawing of the contact mechanism of the present utility model.

[0030] Electromagnetic release 1; yoke 11; attraction side wall 111; accommodating chamber 112; permanent magnet 12; iron core 13; first attraction surface 131; second attraction surface 132; magnetic end cover 14; coil skeleton 15; coil 16; first coil 16a; second coil 16b; push rod 19; blocking member 2; contact mechanism 3; contact support 31; moving contact 32; static contact 33; contact spring 34; rotating shaft 35; connecting rod 36; hinge shaft 37; circuit board 4. DETAILED DESCRIPTION

[0031] The following embodiments are given in conjunction with the accompanying drawings to further illustrate the specific implementation of the electromagnetic release and circuit breaker of the present invention. The electromagnetic release and circuit breaker of the present invention are not limited to the description of the following embodiments.

[0032] like Figure 1 and Figure 2 As shown, the circuit breaker of this embodiment includes a control system, a contact mechanism 3 and an electromagnetic release 1. The structure and principle of the control system are based on the existing technology. The control system generally includes a circuit board 4.

[0033] like Figures 1-4 As shown, the electromagnetic release 1 of this embodiment includes a yoke 11, a permanent magnet 12, an iron core 13, a magnetic end cap 14, a coil bobbin 15, and a coil 16 mounted on the coil bobbin 15. The yoke 11 has an engaging side wall 111 opposite the magnetic end cap 14. The permanent magnet 12 is located between the magnetic end cap 14 and the engaging side wall 111. The iron core 13 is movably disposed within the axial hole of the coil bobbin 15 and is located between the magnetic end cap 14 and the engaging side wall 111. The two ends of the iron core 13 are respectively provided with a first engaging surface 131 opposite the magnetic end cap 14 and a second engaging surface 132 opposite the engaging side wall 111. The iron core 13 is driven and engaged with the contact mechanism 3. In particular, a blocking member 2 is provided between the first engaging surface 131 of the iron core 13 and the magnetic end cap 14. The circuit board 4 of the control system applies a positive voltage to the coil 16, providing a closing driving force for the iron core 13. At this time, the electromagnetic release 1 is in the closed state. Under the action of the closing driving force, the second attraction surface 132 of the iron core 13 is attracted to the attraction side wall 111 of the magnetic yoke 11, so that the iron core 13 drives the contact mechanism 3 to close and provides the contact mechanism 3 with a closing holding force; the circuit board 4 of the control system applies a reverse voltage to the coil 16, providing an opening driving force for the iron core 13. At this time, the electromagnetic release 1 is in the opening state. Under the action of the opening driving force, the iron core 13 is attracted to the magnetic end cover 14, and the iron core 13 drives the contact mechanism 3 to open and provides the contact mechanism 3 with an opening holding force. Due to the presence of the blocking member 2, the first attraction surface 131 of the iron core 13 and the magnetic end cover 14 cannot be attracted together. The first attraction surface 131 of the iron core 13 is blocked by the blocking member 2, and there is a magnetic gap between the first attraction surface 131 of the iron core 13 and the magnetic end cover 14 for weakening the opening holding force.

[0034] like Figure 1 and Figure 4As shown, when the circuit breaker is opened, that is, the electromagnetic release 1 is opened, the permanent magnet 12 forms a magnetic circuit with the yoke 11, the magnetic end cover 14, the iron core 13 and the air gap, and the yoke 11 and the magnetic end cover 14 are magnetized at the same time. When the iron core 13 deviates to the left side of the permanent magnet 12, the magnetic flux on the left side of the permanent magnet 12 is greater than the magnetic flux on the right side of the permanent magnet 12, so the iron core 13 moves closer to the opening position (i.e., moves to the left in the figure), so that the first attraction surface 131 of the iron core 13 and the magnetic end cover 14 attract each other to form an opening holding force. However, due to the presence of the blocking member 2, there is a magnetic gap between the first attraction surface 131 of the iron core 13 and the magnetic end cover 14, which makes the opening holding force relatively weakened. As is well known, the gap between the magnetic conductive parts will cause a certain obstruction to the transmission of the magnetic field between the magnetic conductive parts, thereby causing the electromagnetic force to be weakened. When the electromagnetic release 1 is in the open state, the electromagnetic force of the electromagnetic release 1 (i.e., the open holding force) is weakened due to the magnetic gap between the first engaging surface 131 of the iron core 13 and the magnetic end cap 14. In this embodiment, the electromagnetic release and circuit breaker utilize a blocking member 2 positioned between the first engaging surface 131 of the iron core 13 and the magnetic end cap 14. This creates a magnetic gap when the first engaging surface 131 of the iron core 13 and the magnetic end cap 14 are attracted to each other, thereby reducing the holding force of the electromagnetic release 1 in the open state and, consequently, the power required to close the circuit breaker.

[0035] The blocking member 2 has at least three embodiments, such as Figure 4 and Figure 7 In the embodiment 1 shown, the blocking member 2 is a boss integrally provided on the first engaging surface 131 of the iron core 13. Figure 8 and Figure 9 In the second embodiment shown, the blocking member 2 is a boss integrally mounted on the magnetic end cap 14. The bosses in the first and second embodiments are preferably circular, but may also be other shapes such as square. The blocking member 2 in the first and second embodiments is integrally mounted on the core 13 or the magnetic end cap 14, resulting in a simple structure and ease of manufacturing.

[0036] In the third embodiment of the blocking member 2, the blocking member 2 is a straight plate structure made of non-magnetic material, and the blocking member 2 is fixed on the first attraction surface 131 of the iron core 13 or the magnetic end cover 14. In this embodiment, the blocking member 2 can be a stainless steel plate, which is fixed to the magnetic end cover 14 or the first attraction surface 131 of the iron core 13 by welding or riveting, or it can be an insulating cardboard, which is fixed to the magnetic end cover 14 or the first attraction surface 131 of the iron core 13 by bonding or other fixing methods. The blocking member 2 of this embodiment can be a circular plate, a square plate or other structures. The blocking member 2 made of non-magnetic material is blocked between the first attraction surface 131 of the iron core 13 and the magnetic end cover 14 to weaken the holding force between the iron core 13 and the magnetic end cover 14.

[0037] like Figure 3-Figure 6 As shown, the magnetic yoke 11 is a U-shaped structure, the magnetic end cover 14 covers and is fixed on the opening of the magnetic yoke 11 and forms a receiving cavity 112 with the magnetic yoke 11, the permanent magnet 12 is sleeved on the outer side of the coil skeleton 15, the iron core 13 is slidably set in the axial hole of the coil skeleton 15, and the coil skeleton 15 is installed in the receiving cavity 112 and is located between the magnetic end cover 14 and the attraction side wall 111. Preferably, the permanent magnet 12 is located in the center between the magnetic end cover 14 and the attraction side wall 111. The coil 16 includes a first coil 16a and a second coil 16b respectively wound on the coil skeleton 15, the first coil 16a and the second coil 16b have the same winding direction, and the first coil 16a and the second coil 16b are arranged in parallel, and the permanent magnet 12 is located between the first coil 16a and the second coil 16b. In this embodiment, coil 16 is a dual-coil structure, consisting of a first coil 16a and a second coil 16b wound in the same direction and arranged in parallel. The first coil 16a and the second coil 16b generate magnetic flux in the same direction and serve the same purpose. When the voltage direction is switched, the voltages of the first coil 16a and the second coil 16b switch simultaneously. Of course, coil 16 can also be a single-coil structure.

[0038] like Figure 4 As shown, the iron core 13 is driven to cooperate with the contact mechanism 3 through the push rod 19. One end of the push rod 19 passes through the through hole on the attraction side wall 111 and is fixedly connected to the end of the iron core 13 used to be attracted to the attraction side wall 111. The other end of the push rod 19 is used to drive and cooperate with the contact mechanism 3.

[0039] like Figure 1 and Figure 10-11 As shown, the contact mechanism 3 includes a contact support 31, a movable contact 32, and a contact spring 34 that provides contact pressure for the movable contact 32. The iron core 13 of the electromagnetic tripper 1 is driven and engaged with the contact support 31 of the contact mechanism 3 via a push rod 19. Specifically, the push rod 19 is fixedly connected to a connecting rod 36, and the connecting rod 36 is hinged to the contact support 31 via a hinge shaft 37. One end of the movable contact 32 is rotatably mounted on the contact support 31 via a rotating shaft 35, and the other end of the movable contact 32 is engaged with the static contact 33. Preferably, the contact spring 34 is a torsion spring, which is sleeved on the rotating shaft 35. One end of the contact spring 34 abuts against the contact support 31, and the other end of the contact spring 34 abuts against the movable contact 32.

[0040] like Figure 2As shown, when the circuit breaker is closed, that is, the electromagnetic release 1 is closed, the permanent magnet 12 forms a magnetic circuit with the yoke 11, the magnetic end cap 14, the iron core 13, and the air gap, and simultaneously magnetizes the yoke 11 and the magnetic end cap 14. When the iron core 13 deflects to the right of the permanent magnet 12, the magnetic flux on the right side of the permanent magnet 12 is greater than the magnetic flux on the left side of the permanent magnet 12. Therefore, the iron core 13 moves closer to the closed position (i.e., moves to the right in the figure), causing the iron core 13 to attract the attracting side wall 111 of the yoke 11 to generate a closing holding force. Due to the presence of the contact spring 34, the closing holding force is relatively weakened. The force of the contact spring 34 should be less than the closing driving force when the iron core 13 deflects to the right of the permanent magnet 12. Due to the presence of the blocking member 2, the opening holding force of the circuit breaker is smaller than the closing holding force, that is, the closing driving force is smaller than the opening driving force; at the same time, due to the reaction force of the contact spring 34, the closing holding force is weakened, so that the opening driving force and the closing driving force of the circuit breaker are almost the same, and the opening power and the closing power can be almost the same.

[0041] The circuit breaker of this embodiment has automatic closing and opening functions.

[0042] like Figure 2 As shown, during the automatic closing process of the circuit breaker, the circuit board 4 of the control system receives a closing signal and provides a driving voltage (i.e., the forward voltage) to the coil 16 of the electromagnetic release 1. At this time, the iron core 13 of the electromagnetic release 1 moves to the right, so that the second attraction surface 132 of the iron core 13 is attracted to the attraction side wall 111 of the yoke 11. The push rod 19 moves to the right along with the iron core 13 to drive the moving contact 32 through the connecting rod 36, so that the moving contact 32 and the static contact 33 are closed, thereby closing the circuit breaker.

[0043] like Figure 1 and Figure 4 As shown, during the automatic opening process of the circuit breaker, the circuit board 4 of the control system receives the opening signal and provides a reverse voltage (opposite to the voltage provided when closing) to the coil 16 of the electromagnetic release 1. At this time, the iron core 13 of the electromagnetic release 1 moves to the left, so that the first attraction surface 131 of the iron core 13 is blocked by the blocking member 2, and a magnetic gap is formed between the first attraction surface 131 of the iron core 13 and the magnetic end cover 14. The push rod 19 moves to the left with the iron core 13 to drive the moving contact 32 through the connecting rod 36, so that the moving contact 32 is disconnected from the static contact 33, thereby realizing the opening of the circuit breaker.

[0044] It should be noted that in the description of this utility model, the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, or are conventionally placed directions or positional relationships during use. They are intended solely for ease of description and do not imply that the devices or components referred to must have a specific direction. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third," etc., are used solely for distinction and description and should not be construed as indicating relative importance.

[0045] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. An electromagnetic release, comprising a magnetic yoke (11), a permanent magnet (12), an iron core (13), a magnetic end cover (14), a coil frame (15), and a coil (16) sleeved on the coil frame (15), wherein the magnetic yoke (11) has an attraction side wall (111) opposite to the magnetic end cover (14), the permanent magnet (12) is located between the magnetic end cover (14) and the attraction side wall (111), the iron core (13) is movably arranged in an axial hole of the coil frame (15) and is located between the magnetic end cover (14) and the attraction side wall (111), the two ends of the iron core (13) are respectively provided with a first attraction surface (131) opposite to the magnetic end cover (14) and a second attraction surface (132) opposite to the attraction side wall (111), the iron core (13) is driven and matched with a contact mechanism (3), and is characterized in that: A blocking member (2) is provided between the first attracting surface (131) of the iron core (13) and the magnetic end cover (14). The electromagnetic release (1) is in an opening state, the iron core (13) is attracted to the magnetic end cover (14) under the action of the opening driving force, and the iron core (13) drives the contact mechanism (3) to open and provides the contact mechanism (3) with an opening holding force. The first attraction surface (131) of the iron core (13) is blocked by the blocking member (2), and a magnetic gap is provided between the first attraction surface (131) and the magnetic end cover (14) for reducing the opening holding force.

2. The electromagnetic release according to claim 1, characterized in that: The blocking member (2) is a boss integrally provided on the first attraction surface (131) of the iron core (13); or, the blocking member (2) is a boss integrally provided on the magnetic end cover (14).

3. The electromagnetic release according to claim 1, characterized in that: The blocking member (2) is a straight plate structure made of non-magnetic material, and the blocking member (2) is fixed on the first attraction surface (131) of the iron core (13) or the magnetic end cover (14).

4. The electromagnetic release according to claim 1, characterized in that: The magnetic yoke (11) is a U-shaped structure. The magnetic end cover (14) covers and is fixed on the opening of the magnetic yoke (11) and forms an accommodating cavity (112) with the magnetic yoke (11). The permanent magnet (12) is sleeved on the outer side of the coil frame (15) and is located in the center between the magnetic end cover (14) and the attraction side wall (111). The iron core (13) is slidably arranged in the axial hole of the coil frame (15). The coil frame (15) is installed in the accommodating cavity (112) and is located between the magnetic end cover (14) and the attraction side wall (111).

5. The electromagnetic release according to claim 1, characterized in that: The coil (16) comprises a first coil (16a) and a second coil (16b) respectively wound on a coil frame (15); the first coil (16a) and the second coil (16b) have the same winding direction, and the first coil (16a) and the second coil (16b) are arranged in parallel; the permanent magnet (12) is located between the first coil (16a) and the second coil (16b).

6. The electromagnetic release according to claim 1, characterized in that: The iron core (13) is driven and matched with the contact mechanism (3) through a push rod (19); one end of the push rod (19) passes through a through hole on the attraction side wall (111) and is fixedly connected to one end of the iron core (13) for being attracted to the attraction side wall (111); the other end of the push rod (19) is driven and matched with the contact mechanism (3).

7. A circuit breaker comprising a control system and a contact mechanism (3), characterized in that: It also includes the electromagnetic release described in any one of claims 1 to 6, wherein the control system applies a forward voltage to the coil (16) of the electromagnetic release (1) to provide a closing driving force for the iron core (13) of the electromagnetic release (1); and the control system applies a reverse voltage to the coil (16) of the electromagnetic release (1) to provide an opening driving force for the iron core (13) of the electromagnetic release (1).

8. The circuit breaker according to claim 7, wherein: The contact mechanism (3) comprises a contact support (31), a moving contact (32) and a contact spring (34) for providing contact pressure for the moving contact (32); the iron core (13) of the electromagnetic release (1) is driven to cooperate with the contact support (31) of the contact mechanism (3); one end of the moving contact (32) is rotatably mounted on the contact support (31) via a rotating shaft (35); and the other end of the moving contact (32) cooperates with the static contact (33).

9. The circuit breaker according to claim 8, characterized in that: The iron core (13) is driven and matched with the contact support (31) of the contact mechanism (3) through a push rod (19); the push rod (19) is fixedly connected to a connecting rod (36); and the connecting rod (36) is hinged to the contact support (31) through a hinge shaft (37).

10. The circuit breaker according to claim 8, wherein: The contact spring (34) is a torsion spring, which is sleeved on the rotating shaft (35). One end of the contact spring (34) abuts against the contact support (31), and the other end of the contact spring (34) abuts against the moving contact (32).

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