Electromagnetic drive unit of switching device and switching device

Abstract

An electromagnetic drive unit (10) for a switching device (1) comprises a magnetic core (11) having first, second and third magnetic circuits (111, 112, 113), each magnetic circuit being arranged transversely with respect to a longitudinal axis (L) of the electromagnetic drive unit (10); and an armature (12) configured to be movable along the longitudinal axis (L) between a first and a second state. The electromagnetic drive unit (10) further comprises first and second magnetic coils (14, 15) which are configured to move the armature (12) due to excitation of the first and / or second magnetic coils (14, 5), wherein the first magnetic coil (14) is arranged between the first and second magnetic paths (111, 112) and the second magnetic coil (15) is arranged between the second and third magnetic paths (112, 113) relative to the longitudinal axis (L) and wherein the magnetic core (11) and the magnetic coils (14, 15) are configured to cooperate with each other so that the magnetic flux flowing through the magnetic paths (111, 112, 113) to move the armature (12) between the first and second states is adjustable.

Description

Technical Field

[0001] The present disclosure relates to an electromagnetic drive unit for a switching device and the switching device. Background Art

[0002] The switching device or switching arrangement comprises a contact unit or switching part and an actuating part for setting the switching state of the switching part. Generally, it is a challenge to provide a fast disconnection, especially in case of a short circuit.

[0003] Document EP 2590192 A1 describes a switch for multi-pole direct current operation.

[0004] The present disclosure relates to an electromagnetic drive unit for a switching device and a switching device for switching alternating current and direct current. The electromagnetic drive unit for a switching device and the switching device can be used in the field of electric travel. Summary of the invention

[0005] One object is to provide an electromagnetic drive unit for a switching device and a switching device capable of fast switching.

[0006] This object is achieved by the subject matter of the independent claims. Further developments and embodiments are described in the dependent claims.

[0007] According to one aspect, an electromagnetic drive unit for a switching device includes a magnetic core having first, second and third magnetic circuits, each magnetic circuit being arranged transversely relative to a longitudinal axis of the electromagnetic drive unit and coupled to a longitudinal magnetic support at a respective end to form a magnetic frame structure. The electromagnetic drive unit also includes an armature configured to be movable along the longitudinal axis between a first state and a second state. The electromagnetic drive unit also includes first and second magnetic coils configured to move the armature due to excitation of the first and / or second magnetic coils, wherein the first magnetic coil is arranged between the first and second magnetic circuits and the second magnetic coil is arranged between the second and third magnetic circuits relative to the longitudinal axis, and wherein the magnetic core and the magnetic coils are configured to cooperate with each other so that the magnetic flux flowing through the magnetic circuit to move the armature between the first and second states is adjustable.

[0008] By using the described electromagnetic drive unit, a switching device is feasible at low cost, which switching device can be quickly switched between the on and off states of the switching device by remote control even without using additional permanent magnets. The electromagnetic drive unit implements an active actuator for fast switching dynamics and is activated on the one hand to realize a first state of the armature corresponding to the on state of the switching device and on the other hand to realize a second state of the armature corresponding to the off state of the switching device. The armature is configured to be coupled to a contact bridge of the switching device to realize switching between the first state and the second state of the switching device or the on state and the off state, respectively.

[0009] Due to the described arrangement of the electromagnetic drive unit, a predetermined or default magnetic flux flowing through the first, second and third magnetic circuits spaced apart from each other can be adjusted to actively control the movement of the armature. Therefore, the actuator is also actively controlled to set the disconnect state of the corresponding switching device. Therefore, the de-energization of the holding circuit and the movement in the disconnection direction can be performed very quickly. There is no need to use additional permanent magnets associated with the holding circuit and contributes to a simple and clear configuration of the electromagnetic drive unit.

[0010] The excitation of the individual magnetic coils is caused by applying power or voltage thereto and may also be referred to as magnetization of the individual coils. Thus, de-excitation may also be referred to as demagnetization and may be caused by removing power or voltage from one or more magnetic coils.

[0011] According to an embodiment, the first magnetic coil is configured to face the contact unit relative to the assembly configuration of the switching device and to move the armature to the first state due to the excitation. In addition, the magnetic circuit is configured so that the second magnetic circuit is arranged between the first magnetic circuit and the third magnetic circuit relative to the longitudinal axis. Therefore, relative to the assembly configuration of the switching device, the first magnetic circuit is configured to face the contact unit and the third magnetic circuit is configured to face away from the contact unit. The magnetic circuit and the first magnetic coil are configured to cooperate with each other so that due to the excitation of the first magnetic coil, the magnetic flux basically flows through the first magnetic circuit and the second magnetic circuit, and the magnetic force acts in the direction from the second magnetic circuit to the first magnetic circuit.

[0012] The configuration of the electromagnetic drive unit is capable of controlling the magnetic flux generated by the first and / or second magnetic coils. The first magnetic coil provides a pulling force to move the armature to the first state, for example against an acting spring force. The first magnetic circuit and the second magnetic circuit form a holding circuit and advantageously control the magnetic flux so that the magnetic flux flowing through the third magnetic circuit is as low as possible.

[0013] In a further embodiment, the second magnetic coil is configured to face away from the contact unit relative to the assembly configuration of the switching device and move the armature to a second state due to excitation, wherein the magnetic circuit and the magnetic coil are configured to cooperate with each other so that when the first magnetic coil is de-energized and the second magnetic coil is energized, the magnetic flux flows through all magnetic circuits, reducing or eliminating the holding force and generating a second force opposite to the holding force, thereby generating a magnetic force acting in a direction from the first magnetic circuit to the second magnetic circuit to move or hold the armature in the second state.

[0014] The second magnetic coil implements the disconnection coil, in particular, quickly moves the armature to the second state, for example in cooperation with the acting spring force. In addition, the excitation of the second magnetic coil helps to de-excite the first magnetic coil. Therefore, it is possible to quickly switch and set the disconnection state without using permanent magnets. Starting from the first or on state, the armature is in contact with the first magnetic circuit due to the holding magnetic flux. The de-excitation or demagnetization of the first magnetic coil and the excitation or magnetization of the second magnetic coil result in the generation of a magnetic flux in the magnetic circuit that is opposite to the holding magnetic flux. Therefore, the armature is forced to move away from the first magnetic circuit to the third magnetic circuit, and a gap is formed between the end of the armature and the first magnetic circuit. When the armature contacts the third magnetic circuit with its opposite end, the second or disconnection state is set, and the remaining magnetic flux flows substantially through the second and third magnetic circuits that interact with the armature. Therefore, at the beginning of the disconnection mechanism, the magnetic flux flows through all magnetic circuits. And at the end when the disconnection state is enabled, the magnetic flux through the magnetic core is advantageously controlled so that the corresponding flow through the first magnetic circuit is low.

[0015] The magnetic circuits are coupled via longitudinal struts arranged substantially parallel to the longitudinal axis of the electromagnetic drive unit, which longitudinal axis also presents the longitudinal axis of the corresponding assembled switching device. The first and third magnetic circuits crossing the longitudinal axis realize a magnetic frame structure associated with the longitudinal struts, wherein the second magnetic circuit defines an intermediate strut substantially parallel to and spaced apart from the first and third magnetic circuits.

[0016] According to another embodiment of the electromagnetic drive unit, the first magnetic circuit comprises a curved region coupling the first magnetic circuit to the longitudinal magnetic strut. Such formation of the first magnetic circuit facing the contact unit relative to the assembled state of the switching device can advantageously adjust the magnetic flux passing through the magnetic core to move the armature. The magnetic core may also include a profile with curved regions, recesses and / or protrusions, which are arranged at the magnetic frame structure to advantageously control the magnetic flux, thereby achieving fast switching of the switching device.

[0017] In another embodiment, the armature comprises a flat pole surface at one end and an inclined pole surface at an opposite end relative to the longitudinal axis. The flat pole surface is configured to interact with a flat magnetic surface of the core to set a first state of the armature, and the inclined pole surface is configured to interact with an inclined magnetic surface of the core to set a second state of the armature. The specific design of the interaction of the pole surfaces of the armature and the corresponding magnetic surfaces of the core enables advantageous control of the functions of the electromagnetic drive unit and the switching device.

[0018] The different formation of the opposite pole surfaces for the respective on and off states of the switching device facilitates fast switching and fast movement of the respective first and second states of the armature as well as reliable and stable holding. The flat poles and magnetic surfaces enable a strong holding force relative to the first state or on state while requiring only a low holding force. To pass from the first state to the second state, the inclined pole surfaces generate a strong magnetic flux and thus a high pulling force, which in turn leads to a faster movement of the armature, wherein the excitation of the second magnetic coil is low. As a result, less power is required for movement.

[0019] According to one embodiment, the armature may include flat pole surfaces at both ends interacting with the flat surface of the magnetic core. Alternatively, the armature may include inclined pole surfaces at both ends interacting with the inclined surface of the magnetic core. The inclined surface may also be referred to as a ramp.

[0020] In one embodiment, the magnetic circuit is configured so that the second magnetic circuit is arranged between the first magnetic circuit and the third magnetic circuit relative to the longitudinal axis and includes two separated segments, each segment facing the armature on the opposite side and thereby defining a non-magnetic gap between the corresponding segment and the armature having a predetermined width. Preferably, the gap has a width greater than or equal to 0.2 mm. Preferably, the gap has a width in the range of 0.2 mm to 0.4 mm. Therefore, the second magnetic circuit extends from the opposite side into the inner space of the magnetic frame structure in the direction toward the armature. One end of each segment is coupled to the corresponding magnetic support, while the other free end is arranged close to the movable armature. This configuration advantageously affects the magnetic flux passing through the core and the movement of the armature. The non-magnetic gap between the segment and the armature can be achieved by an insulating layer surrounding the armature, at least in the area where it moves along the segment. Alternatively, the insulating layer can be applied to the surface on the segment facing the armature. The insulating material needs to have a magnetic permeability μ of 1 or close to 1. r It may, for example, be made of a plastic material.

[0021] According to another embodiment of the electromagnetic drive unit, the armature at one end includes an inclined pole surface, which is configured to interact with the inclined surface of the magnetic core to set the second state of the armature, wherein the inclined pole surface and the inclined magnetic surface facing each other define a non-magnetic gap between the armature and the magnetic core in the second state of the armature. The gap has a predetermined width. Preferably, the gap has a width greater than or equal to 0.5 mm in the vertical direction. Preferably, in the second state of the armature, the width of the gap is in the range of 0.5 mm to 1.0 mm. For example, the width of the gap may also depend on the angle of the inclined pole surface. This configuration also advantageously affects the magnetic flux through the magnetic core and the movement of the armature.

[0022] In the present invention it is recognized that the geometric relationship of the gaps, i.e. a) the gap between the segment of the second magnetic circuit and the armature, b) the gap between the flat surface of the armature and the core relative to the first state of the armature, and c) the gap between the inclined surface of the armature and the core relative to the second state of the armature, advantageously affects the magnetic flux through the core and its magnetic circuit and the movement and positioning of the armature in its first and second states, thereby enabling fast and reliable switching between the on and off states of the corresponding switching device.

[0023] Due to the excitation of the first magnetic coil, the armature moves or remains in the first state depending on the on state of the switching device. If the first magnetic coil is no longer excited but the excitation of the second magnetic coil is introduced, a rapid de-excitation of the holding circuit can be achieved, including the first magnetic circuit and the first magnetic coil, etc. In this way, a magnetic attraction toward the disconnected state can be generated. This force can be a supplement to the spring force of the bias spring that tends to continuously act in the direction of the disconnected state. Therefore, if neither the first nor the second magnetic coil is excited, the safe disconnected state of the switching device is maintained.

[0024] In an exemplary embodiment, energization of the second magnetic coil may be initiated based on the capacitor being charged in advance.

[0025] In another exemplary embodiment, relative to the first state of the armature, the non-magnetic gap between the corresponding segment of the second magnetic circuit and the armature and the non-magnetic gap between the armature and the magnetic core are geometrically configured relative to each other. In particular, relative to the first state of the armature, the width of the gap between the armature and the magnetic core (i.e., the non-magnetic gap between the armature and the first magnetic circuit) is smaller than the width of the gap between the corresponding segment of the second magnetic circuit and the armature.

[0026] According to another embodiment of the electromagnetic drive unit, the magnetic core comprises a plurality of metal sheets, each sheet being electrically and magnetically isolated. Such an assembly of the magnetic core enables a low-cost electromagnetic drive unit and helps to minimize the occurrence of undesirable eddy currents.

[0027] The described electromagnetic drive unit can be used to control AC and DC switching devices configured for switching operating currents and short-circuit currents.

[0028] In one embodiment, the switching device includes an electromagnetic drive unit as described above and an embodiment of a contact unit having a first fixed contact and a second fixed contact, a contact bridge, and a first movable contact and a second movable contact arranged at the contact bridge. In the on state of the switching device, the first fixed contact contacts the first movable contact and the second fixed contact contacts the second movable contact, and in the off state of the switching device, the first fixed contact does not contact the first movable contact and the second fixed contact does not contact the second movable contact. The armature of the electromagnetic drive unit is coupled to the contact bridge to set the switching device in the on state or the off state due to the excitation or de-excitation of the first magnetic coil and the corresponding movement of the armature along the longitudinal axis. The second magnetic coil will help to de-excite the magnetic core and at least a portion of the first coil.

[0029] This configuration of the switching device using the described electromagnetic drive unit enables active de-excitation of the first magnetic circuit by de-excitation of the first coil and excitation of the second coil (i.e. by supplying power to the second coil), resulting in a short disconnection time, for example lasting less than 2 ms, thereby facilitating safe operation and avoiding injury or damage.

[0030] It is also to be understood that the described features and characteristics of the electromagnetic drive unit are also disclosed with respect to the switching device, and vice versa, if applicable.

[0031] In a further embodiment, the switching device comprises a spring configured to bias the contact bridge and / or the armature in a direction that sets the switching device in the disconnected state. This permanently acting spring force enables a reliable setting of the disconnected state even if the magnetic coil is not energized. The spring force further supports the magnetic force induced by the second magnetic coil due to the energization and thus increases the speed of the switching operation of the switching device from the on state to the off state.

[0032] According to other embodiments, the switching device includes a first arc extinguishing device having a first pair of arc chambers for extinguishing a first arc originating between a first fixed contact and a first movable contact, and a second arc extinguishing device having a second pair of arc chambers for extinguishing a second arc originating between a second fixed contact and a second movable contact.

[0033] In another embodiment, the switching device comprises a control unit, the output of which is coupled to at least one control input of the electromagnetic drive unit, wherein the control unit is configured to set the switching device to an on state or an off state, depending on a control signal provided by the output of the control unit, so as to energize one or both magnetic coils and control the movement of the armature. For example, the control circuit is configured to set the switching device to an off state in response to an emergency signal received at the control unit. Thus, the control signal may be a command to simultaneously initiate a quick disconnection by de-energizing or demagnetizing the first magnetic coil by disconnecting the power supply and energizing or magnetizing the second magnetic coil by applying the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following description of the figures of the embodiments may further illustrate and explain aspects of the electromagnetic drive unit of the switching device and the switching device. Parts, devices and circuits having the same structure and the same effect appear with equivalent reference symbols. To the extent that parts, devices or circuits correspond to each other in terms of their functions in different figures, their descriptions are not repeated for each subsequent figure. For the sake of clarity, elements may not be marked with corresponding reference symbols in all figures.

[0035] Figure 1A An example of a switching device is shown with an electromagnetic drive unit in a first position;

[0036] Figure 1B showing a switching device with the electromagnetic drive unit in a second position;

[0037] Figure 2A showing a switching device with the electromagnetic drive unit in a first position with the coil removed; and

[0038] Figure 2B showing the switching device with the electromagnetic drive unit in a second position with the coil removed; and

[0039] Figure 3 showing an example of an electromagnetic drive unit for a switching device; and

[0040] Figure 4 Other examples of electromagnetic drive units for display switching devices; DETAILED DESCRIPTION

[0041] Figure 1AAn example of a switching device 1 is shown. The switching device 1 provides a switching function through a contact unit 20 and a driving function through an electromagnetic drive unit 10. The circuit breaker function is explained below. The switching device 20 includes a first fixed contact 21 and a second fixed contact 22, a first movable contact 231 and a second movable contact 232, and a contact bridge 23. The contact bridge 23 can be named a switching bridge. The first movable contact 231 and the second movable contact 232 are fixed on the contact bridge 23.

[0042] like Figure 1A and Figure 2A As shown, in the second disconnected state of the switching device 1 , the first fixed contact 21 does not contact the first movable contact 231 , and the second fixed contact 22 does not contact the second movable contact 232 .

[0043] Figure 1B and Figure 2B It is shown that in the first on-state of the switching device 1 , the first fixed contact 21 contacts the first movable contact 231 , and the second fixed contact 22 contacts the second movable contact 232 .

[0044] Due to the energization of the magnetic coils 14 , 15 and the movement of the armature 12 along the longitudinal axis L of the switching device 1 , the contact bridge 23 couples to the armature 12 of the electromagnetic drive unit 10 to set the switching device 1 in the first or on state or the second or off state.

[0045] Thus, the armature 12 is configured to be movable along the longitudinal axis L in a manner corresponding to the on state of the switching device (see Figure 1B and 2B ) and the disconnected state corresponding to the switching device (see Figure 1A and 2A )’s second state.

[0046] Figure 1A A schematic diagram of a switching device 1 comprising an electromagnetic drive unit ( 10 ) with two magnetic coils 14 and 15 is shown in the open state. Figure 1B A schematic diagram of a switching device 1 with two magnetic coils 14 and 15 is shown in the switched-on state. The coils 14 and 15 are connected to the Figure 2A and 2B , is removed from the corresponding view in order to show possible implementations of the magnetic frame structure of the magnetic core 11 and its magnetic circuits 111 , 112 , 113 .

[0047] The contact unit 20 also includes a first arc extinguishing device 24 for extinguishing a first arc generated between the first fixed contact 21 and the first movable contact 231 and a second arc extinguishing device 25 for extinguishing a second arc generated between the second fixed contact 22 and the second movable contact 232. The switching device 1 may include an arc guiding device 27, which may include a permanent magnet system and one or more arc guiding elements 26, which are coupled to the contact bridge 23 and are configured to guide the generated arc to the corresponding arc extinguishing devices 24, 25.

[0048] The electromagnetic drive unit 10 comprises a magnetic core 11, which is generally made of ferromagnetic material, having first, second and third magnetic circuits 111, 112, 113, each of which is arranged transversely with respect to the longitudinal axis L and coupled at each end to longitudinal magnetic pillars 116, 117 to form a magnetic frame structure. The electromagnetic drive unit 10 also comprises first and second magnetic coils 14, 15, which are configured to move the armature 12 due to the excitation of the first and / or second magnetic coils 14, 15, wherein the first magnetic coil 14 is arranged between the first and second magnetic circuits 111, 112 and the second magnetic coil 15 is arranged between the second and third magnetic circuits 112, 113 with respect to the longitudinal axis L. The magnetic core 11 and the magnetic coils 14, 15 are configured to cooperate with each other so that a predetermined magnetic flux flowing through the magnetic circuits 111, 112, 113 to move the armature 12 between the first and second states is adjustable.

[0049] The first magnetic circuit 111 faces the contact unit 20, while the third magnetic circuit 113 faces away from the contact unit 20. Thus, the second magnetic circuit 112 realizes an intermediate web extending into the inner space of the magnetic frame structure. The first magnetic circuit 111 may include a bent portion at its end, which is coupled to the corresponding magnetic pillars 116 and 117. With regard to the embodiment shown, the magnetic circuits 111, 112, 113 are configured substantially vertically and the magnetic pillars 116, 117 are configured substantially parallel to the longitudinal axis L. In contrast, the magnetic circuits 111, 112, 113 are configured parallel to each other.

[0050] The armature 12 includes a flat pole surface 125 at one end facing the contact unit 20 and an inclined pole surface 124 at the opposite end away from the contact unit 20. The flat pole surface 125 is configured to interact with a flat magnetic surface 115 of the magnetic core 11 arranged at the first magnetic circuit 111 when in the first state of the armature 12. The inclined pole surface 124 is configured to interact with an inclined magnetic surface 114 of the magnetic core 11 formed as a groove at the third magnetic circuit 113 when in the second state of the armature 12. The specific design of the interaction between the pole surfaces 124 and 125 of the armature 12 and the corresponding magnetic surfaces 114 and 115 of the magnetic core 11 can advantageously control the operation of the electromagnetic drive unit 10 and the switching device 1.

[0051] The flat pole surface 125 and the flat magnetic surface 115 enable a strong holding force requiring only a low holding force with respect to the first state or the on state, respectively. To go from the first state to the second state, the inclined pole surface 124 generates a strong magnetic flux resulting in a high pulling force, which in turn results in a faster movement of the armature 12, wherein the excitation of the second magnetic coil 15 is low. Therefore, less power is required for movement.

[0052] In addition, the second magnetic circuit 112 includes at least two separated segments 1121 and 1122, each segment facing the armature 12 at opposite sides, thereby defining a gap 1123 between the respective segments 1121, 1122 and the armature 12. Such a gap 1123 has a predetermined width, preferably in the range of 0.2 mm to 0.4 mm. Such a segmented second magnetic circuit 112 with a free end facing the movable armature 12 advantageously affects the magnetic flux through the core 11 and the movement of the armature 12 and the rapid switching of the switching device 1.

[0053] The inclined pole surface 124 and the inclined magnetic surface 114 facing each other define another gap 17 having a predetermined width between the armature 12 and the third magnetic path 113 of the magnetic core 11 in the second state of the armature 12 (see Figure 1A and 2A ). In the second state of the armature 12, the gap 17 may have a width greater than 0.5 mm, preferably in the range of 0.5 mm to 1.0 mm. This configuration also advantageously affects the magnetic flux through the core 11 and the movement of the armature 12.

[0054] The gap between the poles 124, 125 and the magnetic circuits 111, 113 is realized, for example, as an air gap or as a magnetic field having a relative permeability μ of 1 or close to 1. r In order to maintain the gap in the first and second states, a spacer 18 having a desired thickness may be used (see also Figure 3 and Figure 4 ), and can also be expressed by the relative permeability μ r Made of materials with a value of 1 or close to 1.

[0055] Spacers made of non-magnetic material may also be used for gap (or gaps) 1123 to maintain the gap at a predetermined or minimum distance.

[0056] Therefore, the gap will be referred to as a non-magnetic gap.

[0057] Due to the excitation of the first magnetic coil 14, the armature 12 is moved or held in the first (on) state of the switching device 1. In particular, the described geometrical configuration of the gaps 1123 and 17, i.e. the gap 1123 between the segments 1121, 1122 of the second magnetic circuit 112 and the armature 12 and the gap 17 between the inclined surfaces 114, 124 of the armature 12 and the third path 113 of the core 11 relative to the second state of the armature 12, favorably influences the magnetic flux through the core 11 and its magnetic circuits 111, 112, 113. Since the gap 17 is larger than the gap 1123, the main magnetic flux is directed through the second magnetic circuit 112. Therefore, only a small part of the magnetic flux passes through the third magnetic circuit 113, resulting in a low holding force between the third magnetic circuit 113 and the armature 12, and a large pulling force between the first magnetic circuit 111 and the armature 12. This enables reliable switching between the off and on states of the switching device 1.

[0058] The first magnetic coil 14 and the first and second magnetic circuits 111 , 112 form a holding circuit capable of safely and reliably holding the position of the armature 12 in the first state using a low holding force, but enabling a relatively strong holding force due to the flat pole surface 125 and the flat magnetic surface 115 .

[0059] When the current through the first magnetic coil 14 stops and the coil is no longer energized, the current through the second magnetic coil 15 starts at the same time in the direction opposite to the current flow in the first magnetic coil 14, resulting in Figure 4 The excitation shown can achieve a rapid de-excitation of the holding circuit. According to the size of the gap 17 described, a magnetic attraction force in the direction of the disconnected state can be obtained. In addition, the spring force of the biasing spring can constantly act on the contact bridge 23 and / or the armature 12 in the direction of the disconnected state. Therefore, if both the first and second magnetic coils 14 and 15 are not excited, the safe disconnected state of the switching device 1 is maintained.

[0060] Figure 3 Another schematic diagram of an embodiment of the electromagnetic drive unit 10 is shown in a disconnected state to illustrate the further configuration of the magnetic frame structure of the magnetic core 11 and its magnetic circuits 111, 112, 113. Spacers 18 are arranged at the longitudinal ends of the armature 12 to ensure that the non-magnetic gaps 19, 17 maintain their respective distances in the first and second states, avoiding direct contact between the armature 12 and the magnetic core 11. In addition, the electromagnetic drive unit 10 may include one or more damping elements 126 to offset vibrations caused by the armature 12 impacting the magnetic core 11. In addition, for reasons of mass reduction, the armature 12 may include one or more recesses 122, resulting in faster acceleration or speed of the armature 12 or lower excitation required to force the armature 12 to move.

[0061] Figure 4Another schematic diagram of an embodiment of the electromagnetic drive unit 10 is shown in an on state to illustrate another possible configuration of the magnetic frame structure of the magnetic core 11 and its magnetic circuits 111, 112, 113. The armature 12 includes inclined pole surfaces 124 and 125 at each longitudinal end. The magnetic core 11 also includes complementary inclined magnetic surfaces 114 and 115 formed at the first magnetic circuit 111 and the third magnetic circuit 113, which are configured to interact with the inclined pole surfaces 124, 125 of the armature 12, respectively.

[0062] The inclined magnetic surfaces 114 and 115 of the magnetic core 11 are formed by corresponding protrusions extending into the inner space of the magnetic frame structure. They include a corresponding conical profile in the direction of the corresponding first or third magnetic circuit 111, 113 and a flat part connecting the conical parts. Different angles of the conical parts and / or longer and shorter flat parts or even no flat parts of the interaction surfaces 114 and 124 and / or 115 and 125 can also achieve the above characteristics.

[0063] Spacers 18 may be used at both ends to provide sufficient distance for the non-magnetic gaps 19, 17 in the respective first and second states.

[0064] In an exemplary embodiment, the gap 17 in the second state may be larger than the gap 1123 between the armature 12 and the second magnetic circuit 112, and the gap 1123 may be larger than the gap 19 in the first state. Therefore, the spacer 18 for the gap 17 may be thicker than the spacer on the lateral side around the armature 12 (i.e., for the gap 1123), which in turn may be thicker than the spacer 18 for the gap 19 in the first state.

[0065] In an exemplary embodiment, the spacers 18 of gap 17 may have a thickness >0.5 mm, preferably between 0.5 and 1 mm, the spacers of gap 1123 may have a thickness of 0.2-0.4 mm, and the spacers 18 of gap 19 may have a thickness less than 0.2 mm, for example between 0.05 and 0.18 mm.

[0066] In addition, two different magnetic flux MF are shown. ON and MF OFF Magnetic flux MF ON Relevant to the holding operating mode to be able to safely and reliably maintain the first state of the armature 12 and the corresponding switched-on state of the switching device 1. Magnetic flux MF OFF It is related to the switching operating mode to enable the second state of the armature 12 and the corresponding open state of the switching device 1 .

[0067] The holding operation mode is configured so that the magnetic flux MF ONFlows through the first magnetic circuit 111, flows through a portion of the magnetic support 116 or a portion of the magnetic support 117 between the first and second magnetic circuits 112, flows through the second magnetic circuit 112 and the corresponding segment 1121 or 1122 interacting with the armature 12, flows through the inclined pole surface 125 and the inclined magnetic surface 115 back to the first magnetic circuit 111 to close the corresponding magnetic loop. No magnetic flux or at least very low magnetic flux flows through the third magnetic circuit 113, so that the on state can be safely and reliably maintained by a strong holding force combined with a relatively low holding force.

[0068] The magnetic field directions of the individual magnetic coils 14 are further indicated inside the depicted elements.

[0069] The switching operation mode for switching from the on state to the off state is configured by switching on the current in the coil 15 in a specified direction opposite to the direction of the current in the coil 14, thereby generating a magnetic flux MF OFF Magnetic flux MF OFF Flows through the third magnetic circuit 113 and flows through the magnetic pillars 116 and 117. Here, a part of the magnetic flux branches into the second magnetic circuit 112, and another part flows into the magnetic circuit 111 through the magnetic pillars 116 and 117, and flows into the armature 12 through the inclined magnetic surface 115 and the inclined pole surface 125. Here, it meets the branched magnetic flux passing through the second magnetic circuit 112 and enters the armature 12 through the gap 1123. Magnetic flux MF OFF The loop is closed by the gap 17 from the armature 12 to the third magnetic circuit 113. The division of the magnetic flux passing through the third magnetic circuit 113 into the second magnetic circuit 112 and the first magnetic circuit 111 depends on the size of the non-magnetic gap 1123 and the non-magnetic gap 19.

[0070] When the current in coil 15 is turned on, the current in coil 14 responsible for the magnetic flux MF can be turned off. ON However, the magnetic flux MF 0N By supplying a current in the second magnetic coil 15 in a direction opposite to the current in the first magnetic coil 14, the magnetic flux MF generated by the second magnetic coil OFF has the same magnetic flux MF as the first magnetic circuit 111 0N This causes the magnetic flux in the first magnetic circuit 111 to return to 0 more quickly, thereby reducing the holding force of the armature 12 in the first (on) position more quickly.

[0071] Therefore, due to the relatively strong magnetic force acting on the armature in the direction toward the third magnetic circuit 113, the magnetic flux MF OFF It can quickly switch to the disconnected state. In addition, the magnetic flux MF OFF The magnetic flux MF in the first magnetic circuit 111 generated by the first magnetic coil 14ON de-energization, which further advantageously affects the rapid switching of the switching device 1 to the disconnected state.

[0072] Magnetic flux MF ON and MF OFF This is achieved by the specific magnetic frame structure of the magnetic core 11 , in particular by the design of the magnetic circuits 111 , 112 and 113 in coordination with the magnetic coils 14 , 15 .

[0073] In particular, the dimensions of the gaps 17 and 1123 and of the further gap 19 between the longitudinal ends of the armature 12 facing the first magnetic circuit 111 allow the desired magnetic flux MF to pass through the core 11. ON and MF OFF precise configuration.

[0074] The described electromagnetic drive unit 10 can achieve a fast disconnection action with a duration of less than 2ms and thus facilitate safe operation and avoid injury or damage in the event of overcurrent or short circuit. In particular, the cooperative configuration of the magnetic core 11 and the magnetic coils 14, 15 can advantageously control the magnetic flux and the acting magnetic force.

[0075] The geometry of the opposing pole surfaces 124 and 125 of the armature 12 for switching the respective on and off states of the device 1 further facilitates quick disconnection and quick movement as well as reliable and stable maintenance of the first and second states 12 of the armature.

[0076] Component Symbol

[0077] 1 Switch device

[0078] 10 Electromagnetic drive unit

[0079] 11 Magnetic core

[0080] 111 First Magnetic Circuit

[0081] 112 Second Magnetic Circuit

[0082] 1121 Segment of the second magnetic circuit

[0083] 1122 Segment of the second magnetic circuit

[0084] 1123 Gap (between armature and second magnetic circuit)

[0085] 113 Third Magnetic Circuit

[0086] 114 Inclined Magnetic Surface

[0087] 115 Flat magnetic surface

[0088] 116 Magnetic Pillar

[0089] 117 Magnetic Pillar

[0090] 12 Armature

[0091] 122 recess

[0092] 124 Tilted polar surface

[0093] 125 Flat Surface

[0094] 126 Damping element

[0095] 14 First magnetic coil

[0096] 15 Second magnetic coil

[0097] 17 Gap (between armature and third magnetic circuit)

[0098] 18 Spacer

[0099] 19 Gap (between armature and first magnetic circuit)

[0100] 20 Contact elements

[0101] 21 First fixed contact

[0102] 22 Second fixed contact

[0103] 23 Contact bridge

[0104] 231 First movable contact

[0105] 232 second movable contact

[0106] 24, 25 Arc extinguishing equipment

[0107] 26 Arc guide element

[0108] 27 Arc guiding equipment

[0109] MF ON magnetic flux

[0110] MF OFF magnetic flux

Claims

1. An electromagnetic drive unit (10) for a switching device (1), comprising: - a magnetic core (11) having first, second and third magnetic circuits (111, 112, 113), each magnetic circuit being arranged transversely with respect to the longitudinal axis (L) of the electromagnetic drive unit (10) and coupled at respective ends to longitudinal magnetic struts (116, 117) to form a magnetic frame structure, - an armature (12) configured to be movable along said longitudinal axis (L) between a first state and a second state, and - first and second magnetic coils (14, 15), the first and second magnetic coils (14, 15) being configured to move the armature (12) due to excitation of the first and / or second magnetic coils (14, 15), wherein the first magnetic coil (14) is arranged between the first and second magnetic paths (111, 112), and the second magnetic coil (15) is arranged between the second and third magnetic paths (112, 113) relative to the longitudinal axis (L), and wherein the magnetic core (11) and the magnetic coils (14, 15) are configured to cooperate with each other so that the magnetic flux (MF) flowing through the magnetic paths (111, 112, 113) to move the armature (12) between the first and second states ON MF OFF ) is adjustable, wherein the armature (12) includes an inclined pole surface (124) at one end relative to the longitudinal axis (L), the inclined pole surface (124) being configured to interact with the inclined magnetic surface (114) of the magnetic core (11) to set the second state of the armature (12), and wherein in the second state of the armature (12), a gap (17) having a predetermined width is defined between the inclined pole surface (124) and the inclined magnetic surface (114) between the armature (12) and the magnetic core (11), wherein the first magnetic coil (14) is configured to face the contact unit (20) relative to the assembled configuration of the switching device (1) and to move the armature (12) to a first state due to the excitation, and The magnetic circuits (111, 112, 113) are configured such that the second magnetic circuit (112) is arranged between the first and third magnetic circuits (111, 113) relative to the longitudinal axis (L), and the first magnetic circuit (111) is configured to face the contact unit (20), and the third magnetic circuit (113) is configured to face away from the contact unit (20), and the magnetic circuits (111, 112, 113) and the first magnetic coil (14) are configured to cooperate with each other so that due to the excitation of the first magnetic coil (14), the magnetic flux basically flows through the first and second magnetic circuits (111, 112), and the magnetic force acts in the direction from the second magnetic circuit (112) to the first magnetic circuit (111) to move or keep the armature (12) in a first state.

2. The electromagnetic drive unit (10) according to claim 1, comprising: wherein the second magnetic coil (15) is configured to face away from the contact unit (20) relative to the assembled configuration of the switching device (1) and moves the armature (12) to the second state due to the excitation, and - wherein the magnetic circuits (111, 112, 113) are configured such that the second magnetic circuit (112) is arranged between the first and third magnetic circuits (111, 113) relative to the longitudinal axis (L), and the first magnetic circuit (111) is configured to face the contact unit (20), and the third magnetic circuit (113) is configured to face away from the contact unit (20), and the magnetic circuits (111, 112, 113) and the magnetic coils (14, 15) are configured to cooperate with each other so that when the first magnetic coil (14) is de-energized and the second magnetic coil (15) is energized, the magnetic flux flows through the magnetic circuits (111, 112, 113) to generate a magnetic force acting in a direction from the first magnetic circuit (111) to the second magnetic circuit (112) to move or keep the armature (12) in a second state.

3. The electromagnetic drive unit (10) according to claim 1 or 2, The first magnetic circuit (111) includes a curved region coupling the first magnetic circuit (111) to the longitudinal magnetic pillars (116, 117).

4. The electromagnetic drive unit (10) according to claim 1, wherein the armature (12) comprises a flat pole surface (125) at one end and an inclined pole surface (124) at an opposite end relative to the longitudinal axis (L), and The flat pole surface (125) is configured to interact with the flat magnetic surface (115) of the magnetic core (11) to set a first state of the armature (12), and the inclined pole surface (124) is configured to interact with the inclined magnetic surface (114) of the magnetic core (11) to set a second state of the armature (12).

5. The electromagnetic drive unit (10) according to claim 1, wherein the magnetic circuits (111, 112, 113) are configured such that the second magnetic circuit (112) is arranged between the first and third magnetic circuits (111, 113) relative to the longitudinal axis (L) and comprises two separate segments (1121, 1122) facing the armature (12) at opposite sides, and The non-magnetic gap (1123) between the corresponding segments (1121, 1122) of the second magnetic circuit (112) and the armature (12) has a predetermined width.

6. The electromagnetic drive unit (10) according to claim 5, The gap (1123) between the corresponding segments (1121, 1122) of the second magnetic circuit (112) and the armature (12) has a width greater than or equal to 0.2 mm.

7. The electromagnetic drive unit (10) according to claim 1, in, With respect to the second state of the armature (12), a gap (17) between the armature (12) and the magnetic core (11) has a width greater than or equal to 0.5 mm.

8. The electromagnetic drive unit (10) according to claim 5, In the second state of the armature (12), the width of the gap (1123) between the corresponding segments (1121, 1122) of the second magnetic circuit (112) and the armature (12) is smaller than the gap (17) between the armature (12) and the magnetic core (11).

9. The electromagnetic drive unit (10) according to claim 8, in, Relative to the first state of the armature (12), the width of the non-magnetic gap (17) between the armature (12) and the magnetic core (11) is smaller than the width of the gap (1123) between the corresponding segments (1121, 1122) of the second magnetic circuit (112) and the armature (12).

10. The electromagnetic drive unit (10) according to claim 1, The magnetic core (11) comprises a plurality of metal sheets, each of which is electrically and magnetically isolated.

11. A switching device (1), comprising: - An electromagnetic drive unit (10) according to any one of claims 1 to 10, and a contact unit (20) having a first and a second fixed contact (21, 22), a contact bridge (23) and a first and a second movable contact (231, 232) arranged at the contact bridge (23), wherein in the switched-on state of the switching device (1), the first fixed contact (21) contacts the first movable contact (231), and the second fixed contact (22) contacts the second movable contact (232), wherein in the disconnected state of the switching device (1), the first fixed contact (21) does not contact the first movable contact (231), and the second fixed contact (22) does not contact the second movable contact (232), - wherein the armature (12) of the electromagnetic drive unit (10) is coupled to the contact bridge (23) to set the switching device (1) in an on-state due to the excitation of the first magnetic coil (14) or in an off-state due to the de-excitation of the first magnetic coil (14) and a corresponding movement of the armature (12) along the longitudinal axis (L).

12. The switching device (1) according to claim 11, comprising A spring is configured to bias the contact bridge (23) and / or the armature (12) in a direction that sets the switching device (1) in an off state.

13. A switching device (1) according to claim 12, wherein the armature (12) of the electromagnetic drive unit (10) is coupled to the contact bridge (23) to set the switching device (1) in a disconnected state due to the excitation of the second magnetic coil (15), generating a magnetic force acting in the direction of the spring force of the bias spring.

14. The switching device (1) according to any one of claims 11 to 13, comprising: - a first arc extinguishing device (24) comprising a first pair of arc chambers for extinguishing a first arc originating between the first fixed contact (21) and the first movable contact (231), and - a second arc extinguishing device (25) comprising a second pair of arc chambers for extinguishing a second arc originating between the second fixed contact (22) and the second movable contact (232).

15. The switching device (1) according to any one of claims 11 to 13, comprising: a control unit having an output coupled to at least one control input of the electromagnetic drive unit (10), wherein the control unit is configured to set the switching device (1) in an on-state or an off-state, depending on a control signal provided by the output of the control unit to control the movement of the magnetic coils (14, 15) and thus the armature (12), and The control unit is configured to set the switching device (1) in an off state.

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