Patent Description:
With emergence of electric power, switching devices play an important role in many production processes and technical devices. A switching device performs two functions in a power system: <NUM>. a control function: putting some power devices or lines into operation or stopping them from operating according to an operating requirement of the power system; <NUM>. a protection function: when a power device or line fails, quickly removing a failed part from the power system, to ensure normal operating of a failure-free part of the power system.

In the conventional technology, a switching device is usually connected to a power system through a mechanical connection. To be specific, a wire entry/exit terminal is connected to an external wire or copper bar by using a screw. In this connection manner, due to a large quantity of contacts and impact of a space environment or the like, an installation environment is limited, and poor electrical contact is likely to occur, causing a safety accident. Document <CIT> describes a fixed contact with an integrated structure for a cam switch, and the fixed contact comprises a contact part, a connecting part and a welding needle which are integrally formed. Document <CIT> describes a cam rotary switch with double positive break contacts solderable on an electronic board. Document <CIT> describes a rotation mechanism for a rotary switch and a method of operating the rotary switch. Document <CIT> describes a rotation type isolating switch contact module. Document <CIT> describes a single-pole breaking unit comprising a rotary contact bridge, a switchgear device, and a circuit breaker comprising such a unit. Document <CIT> describes a miniature direct current switch including an insulating shell.

An objective of the present invention is to provide a switch unit and a switching device, to reduce a quantity of contact connections, simplify a connection manner, and improve safety during use.

Embodiments of the present invention are implemented as follows.

According to the present invention, a switch unit is provided, including at least one stationary contact assembly. Each stationary contact assembly includes a first stationary contact, a second stationary contact, and a first pin connected to the first stationary contact. The first pin is soldered to a circuit board.

According to the present invention, the stationary contact assembly further includes a second pin connected to the second stationary contact, the first stationary contact and the first pin are integrally molded, the second stationary contact and the second pin are integrally molded, and the second pin is soldered to the circuit board.

Optionally, the stationary contact assembly further includes a connector, one terminal of the connector is connected to the second stationary contact, and the other terminal is connected to the circuit board.

Optionally, a wiring terminal is disposed on the first stationary contact and/or the second stationary contact, and when the wiring terminal is used for connecting a wire, the wire extends in a preset direction.

Optionally, the switch unit further includes an auxiliary pin, one terminal of the auxiliary pin is connected to the first stationary contact or the second stationary contact, and the other terminal is soldered to the circuit board.

Optionally, a first protrusion is disposed on the first stationary contact, the first protrusion is located on one side of the first stationary contact and faces a side on which an electric arc is produced, a second protrusion is disposed on the second stationary contact, and the second protrusion is located on one side of the second stationary contact and faces a side on which an electric arc is produced.

According to the present invention, the switch unit further includes a housing, the first pin includes a first bending portion connected to the first stationary contact and a first extending portion connected to the first bending portion, the first extending portion and the first stationary contact are located on different planes, the first pin is away from an arc discharge opening of the housing, the second pin includes a second bending portion connected to the second stationary contact and a second extending portion connected to the second bending portion, the second extending portion and the second stationary contact are located on different planes, and the second pin is away from the arc discharge opening.

Optionally, the switch unit further includes a housing and a permanent magnet disposed in the housing, an arc extinguishing area is formed when a movable contact is disconnected from the first stationary contact or the second stationary contact, the permanent magnet corresponds to the arc extinguishing area, and an included angle between a straight line on which a magnetic blowout force applied by the permanent magnet to an electric arc in the arc extinguishing area is located and an orthographic projection of the straight line on a motion plane of the movable contact is greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees.

Optionally, a limiting portion is disposed on the housing, and is configured to limit a position of the first pin and/or the second pin.

Optionally, the limiting portion includes a limiting groove and a clamping protrusion, the limiting groove and the clamping protrusion are separately located on two sides of the housing in a stacking direction, the first pin and/or the second pin pass through the limiting groove, and when housings are stacked, a limiting groove and a clamping protrusion on adjacent housings are clamped, to limit the position of the first pin and/or the second pin; or the limiting portion is a limiting via, and the first pin and/or the second pin pass through the limiting via.

Optionally, an arc discharge opening is provided on the housing, an arcing space connected to the arc discharge opening is correspondingly provided in the housing, a boss is further disposed in the housing, and the boss is located in the arcing space, so that the arcing space forms a channel whose size gradually decreases and then increases.

Optionally, the first extending portion and the second extending portion separately extend out from sides of the housing, and the first extending portion and the second extending portion are separately located on adjacent sides of the housing or opposite sides of the housing.

According to another aspect of embodiments of this application, a switching device is provided, including the switch unit according to any one of the foregoing implementations, where switch units are stacked by using housings.

Optionally, the switching device further includes an arc partition board, the arc partition board includes a plurality of isolation chambers, and the isolation chambers are in a one-to-one correspondence with first pins and/or second pins of the switch units, to block charged particles.

Optionally, the arc partition board and the housing are integrally molded, or the arc partition board and the housing are separately disposed.

Optionally, a first stationary contact and a second stationary contact are diagonally arranged in the switch unit, and stationary contact assemblies in adjacent switch units are arranged in a staggered manner.

Optionally, a baffle plate and a fastener connected to a stationary contact assembly are disposed on one side of the housing, and the fastener is located between two baffle plates of adjacent housings.

Beneficial effects of embodiments of the present invention include:
In the switch unit and the switching device provided in embodiments of this application, each stationary contact assembly includes a first stationary contact, a second stationary contact, and a first pin connected to the first stationary contact. When the switching device is connected to a circuit board, the switching device is directly connected to the circuit board through the first pin, without using a binding post, thereby reducing a quantity of accidents caused by poor electrical contact. An appropriate connection manner is used for the second stationary contact according to an actual requirement, to adapt to a space limitation and improve flexibility of wiring. In the foregoing manner, a quantity of manual contacts in a conventional connection manner can be reduced, a quantity of contact connections can be reduced, a connection manner can be simplified, and safety during use can be improved.

To describe technical solutions in embodiments of the present application more clearly, the following briefly describes accompanying drawings used for describing embodiments. It should be understood that the accompanying drawings show only some embodiments of the present application, and therefore should not be considered as a limitation on the scope. A person of ordinary skill in the art may still derive other related drawings from these accompanying drawings without creative efforts.

Reference numerals: <NUM>: switch unit; <NUM>: circuit board; <NUM>: wire; <NUM>: stationary contact assembly; <NUM>: first stationary contact; <NUM>: first protrusion; <NUM>: first pin; <NUM>: first bending portion; <NUM>: first extending portion; <NUM>: second stationary contact; <NUM>: second protrusion; <NUM>: second pin; <NUM>: second bending portion; <NUM>: second extending portion; <NUM>: connector; <NUM>: wiring terminal; <NUM>: auxiliary pin; <NUM>: housing; <NUM>: limiting via; <NUM>: arc discharge opening; <NUM>: arcing space; <NUM>: permanent magnet; <NUM>: straight line on which a magnetic blowout force is located; <NUM>: boss; <NUM>: limiting groove; <NUM>: baffle plate; <NUM>: clamping protrusion; <NUM>: fastener; <NUM>: movable contact; <NUM>: motion plane; <NUM>: switching device; <NUM>: arc partition board; and <NUM>: isolation chamber.

It should be noted that similar reference numerals and letters represent similar items in the following accompanying drawings, and therefore if an item is defined in an accompanying drawing, the item does not need to be further defined or explained in subsequent accompanying drawings. In addition, the terms "first", "second", and the like are merely intended for differentiated description, and should not be construed as an indication or an implication of relative importance.

In descriptions of the present application, it should be further noted that, unless otherwise specified and limited, the terms "dispose" and "connect" should be understood in a broad sense. For example, a "connection" may be a fixed connection, a detachable connection, or an integrated connection; may be a mechanical connection or an electrical connection; or may be a direct connection, an indirect connection through an intermediate medium, or an internal connection between two components. A person of ordinary skills in the art may understand specific meanings of the foregoing terms in the present application according to specific circumstances.

As shown in <FIG>, an embodiment of this invention provides a switch unit <NUM>, used in a switching device, for example, a rotary switch, an isolation switch, or a circuit breaker. The switch unit <NUM> includes at least one stationary contact assembly <NUM>. Each stationary contact assembly <NUM> includes a first stationary contact <NUM>, a second stationary contact <NUM>, and a first pin <NUM> connected to the first stationary contact <NUM>. The first pin <NUM> is soldered to a circuit board <NUM>.

Specifically, the stationary contact assembly <NUM> includes the first stationary contact <NUM> and the first pin <NUM> electrically connected to the first stationary contact <NUM>, where the first stationary contact <NUM> is connected to a movable contact, and the first pin <NUM> is soldered to the circuit board <NUM> to form a connection path. The first stationary contact <NUM> and the first pin <NUM> are integrally molded, and a required electrical connection relationship may be formed for the second stationary contact <NUM> through wiring. In the foregoing manner, wiring and installation manners for transmission are changed. This helps improve stability of wiring, avoid excessive manual contacts, improve stability of a connection, and improve connection efficiency.

During fixed connection, the first pin <NUM> may be soldered to the circuit board <NUM> through wave soldering. In addition, during connection, a soldering device may be used to perform automatic soldering. This is suitable for mass production, and helps reduce labor costs and improve connection efficiency. In addition, during actual use, an electronic component inserted the circuit board <NUM>, the switching device <NUM>, and the circuit board <NUM> may form a whole. This helps reduce a quantity of contacts (that is, points for wiring) in subsequent use and simplify a connection manner.

It may be understood that the switch unit <NUM> has movable contacts for respectively connecting to the first stationary contact <NUM> and the second stationary contact <NUM>, so that a connection path is formed when the movable contacts are respectively connected to the first stationary contact <NUM> and the second stationary contact <NUM>. The movable contacts may perform a required spatial action based on a contact support, to implement a required switching-off or switching-on operation.

In the switch unit <NUM> provided in this embodiment of this invention, each stationary contact assembly <NUM> includes a first stationary contact <NUM>, a second stationary contact <NUM>, and a first pin <NUM> connected to the first stationary contact <NUM>. When the switching device is connected to the circuit board <NUM>, the switching device may be directly connected to the circuit board <NUM> through the first pin <NUM>, without using a binding post, thereby reducing a quantity of accidents caused by poor electrical contact. An appropriate connection manner may be used for the second stationary contact <NUM> according to an actual requirement, to adapt to a space limitation and improve flexibility of wiring. In the foregoing manner, a quantity of manual contacts in a conventional connection manner can be reduced, a quantity of contact connections can be reduced, a connection manner can be simplified, and safety during use can be improved.

As shown in <FIG>, according to the present invention, the stationary contact assembly <NUM> further includes a second pin <NUM> connected to the second stationary contact <NUM>. The first stationary contact <NUM> and the first pin <NUM> are integrally molded. The second stationary contact <NUM> and the second pin <NUM> are integrally molded. The second pin <NUM> is soldered to the circuit board <NUM>.

Specifically, according to the present invention, the first stationary contact <NUM> and the first pin <NUM> are integrally molded, and the second stationary contact <NUM> and the second pin <NUM> are also integrally molded. In this case, the switch unit <NUM> is soldered to the circuit board <NUM> through the first pin <NUM> and the second pin <NUM>. This facilitates integrated disposing of a product, and helps reduce workload of a user during wiring.

As shown in <FIG>, the stationary contact assembly <NUM> further includes a connector <NUM>. One terminal of the connector <NUM> is connected to the second stationary contact <NUM>, and the other terminal is connected to the circuit board <NUM>.

Specifically, the connector <NUM> may be a flexible connector or a rigid connector. In this way, diversity of connection manners can be improved according to an actual requirement. For example, as shown in <FIG>, when a flexible connector, for example, a copper wire, is used, and when the switch unit <NUM> needs to be electrically connected to a circuit board <NUM>, the electrical connection can be better performed, avoiding difficulty in fitting due to a deviation of a hole position. This helps improve operability of an actual operation. As shown in <FIG>, when a rigid connector, for example, a copper plate, is used, specific support may be provided during connection, preventing excessive flexibility from affecting a wiring speed. This further facilitates connection and fastening.

As shown in <FIG> and <FIG>, a wiring terminal <NUM> is disposed on the first stationary contact <NUM> and/or the second stationary contact <NUM>. When the wiring terminal <NUM> is used for connecting a wire <NUM>, the wire <NUM> extends in a preset direction.

In a case not covered by the present invention, when the switch unit <NUM> is connected to the circuit board <NUM>, and when the switch unit <NUM> is connected to the circuit board <NUM> through the first wiring pin <NUM> or the second wiring pin <NUM>, soldering may not be suitable for wiring due to impact of an installation environment. In this case, the wire <NUM> may be connected to the wiring terminal <NUM>, and the wire <NUM> is led to a side of the switching device on which an operation can be performed more easily. This helps improve applicability during use.

As shown in <FIG>, the switch unit <NUM> further includes an auxiliary pin <NUM>. One terminal of the auxiliary pin <NUM> is connected to the first stationary contact <NUM> or the second stationary contact <NUM>, and the other terminal is soldered to the circuit board <NUM>. Specifically, the auxiliary pin <NUM> is disposed on the first stationary contact <NUM> or the second stationary contact <NUM>. The auxiliary pin <NUM> is soldered to the circuit board <NUM>, to implement grounding through the auxiliary pin <NUM>. When a lightning strike occurs, a current is led to the ground. This can protect the switch unit <NUM>, and helps improve stability of the product during use.

As shown in <FIG>, a first protrusion <NUM> is disposed on the first stationary contact <NUM>, the first protrusion <NUM> is located on one side of the first stationary contact <NUM> and faces a side on which an electric arc is produced, a second protrusion <NUM> is disposed on the second stationary contact <NUM>, and the second protrusion <NUM> is located on one side of the second stationary contact <NUM> and faces a side on which an electric arc is produced.

Specifically, the first protrusion <NUM> and the second protrusion <NUM> mainly use a characteristic of arcing at a conductor tip. When the movable contact <NUM> is disconnected from the first stationary contact <NUM> or the second stationary contact <NUM>, a produced electric arc runs on the first stationary contact <NUM> or the second stationary contact <NUM>, thereby preventing the electric arc from splashing and affecting normal and stable use of the switching device <NUM>.

As shown in <FIG>, the switch unit <NUM> further includes a housing <NUM>. The first pin <NUM> includes a first bending portion <NUM> connected to the first stationary contact <NUM> and a first extending portion <NUM> connected to the first bending portion <NUM>. The first extending portion <NUM> and the first stationary contact <NUM> are located on different planes, and the first pin <NUM> is away from an arc discharge opening <NUM> of the housing <NUM>. The second pin <NUM> includes a second bending portion <NUM> connected to the second stationary contact <NUM> and a second extending portion <NUM> connected to the second bending portion <NUM>. The second extending portion <NUM> and the second stationary contact <NUM> are located on different planes, and the second pin <NUM> is away from the arc discharge opening <NUM>.

Specifically, by using the first pin <NUM> and the first bending portion <NUM>, the first pin <NUM> can be better attached to the housing <NUM>, and stability of the connection is improved. In addition, the first pin <NUM> avoids the arc discharge opening <NUM>. The first pin <NUM> is disposed away from the arc discharge opening <NUM>, so that when charged particles are produced between the movable contact <NUM> and the stationary contact, the charged particles are prevented from splashing onto the first pin <NUM> through the arc discharge opening <NUM> and causing a short circuit of the stationary contact assembly <NUM>. This helps improve stability of an electrical connection.

Similarly, the second pin <NUM> includes the second bending portion <NUM>, so that the second pin <NUM> is better attached to the housing <NUM>, and stability of the connection is improved. In addition, the second pin <NUM> avoids the arc discharge opening <NUM>. The second pin <NUM> is disposed away from the arc discharge opening <NUM>, so that when charged particles are produced between the movable contact <NUM> and the stationary contact, the charged particles are prevented from splashing onto the second pin <NUM> through the arc discharge opening <NUM> and causing a short circuit of the connector <NUM>. This helps improve stability of an electrical connection. It may be understood that, in a case not covered by the present invention, the second stationary contact <NUM> is connected to the circuit board <NUM> by using the connector <NUM>, the connector <NUM> may also be disposed away from the arc discharge opening <NUM>, to ensure stability of the connection.

As shown in <FIG>, the switch unit <NUM> further includes a housing <NUM> and a permanent magnet <NUM> disposed in the housing <NUM>. An arc extinguishing area is formed when the movable contact <NUM> is disconnected from the first stationary contact <NUM> or the second stationary contact <NUM>, and the permanent magnet <NUM> corresponds to the arc extinguishing area. In addition, an included angle between a straight line <NUM> on which a magnetic blowout force applied by the permanent magnet <NUM> to an electric arc in the arc extinguishing area is located and an orthographic projection of the straight line on a motion plane <NUM> of the movable contact <NUM> is greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees.

Specifically, when a position and a posture of the permanent magnet <NUM> change, correspondingly, the magnetic blowout force applied to the electric arc also deflects at a specific angle, and the straight line on which the magnetic blowout force is located also correspondingly deflects at the same angle. Therefore, as a deflection direction or the position of the permanent magnet <NUM> changes, the included angle α between the straight line <NUM> on which the magnetic blowout force is located and the orthographic projection of the straight line on the motion plane <NUM> may correspondingly deflect from <NUM> degrees to <NUM> degrees. For example, the included angle may be set to <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, or <NUM> degrees. When the angle is not <NUM> degrees, a thickness of the switch unit <NUM> can be further reduced. This helps improve space utilization.

In the foregoing manner, under the action of the magnetic blowout force, the electric arc extends along a direction of the magnetic blowout force. When the included angle between the straight line <NUM> on which the magnetic blowout force applied to the electric arc is located and the orthographic projection of the straight line on the motion plane <NUM> of the movable contact <NUM> is greater than or equal to <NUM> degrees and less than or equal to <NUM> degrees, an arc extending space is larger. This helps increase an arc extinguishing speed. This can also avoid blocking by another component in the housing <NUM>, thereby helping improve an arc extinguishing effect.

Still as shown in <FIG>, an arc discharge opening <NUM> is provided on the housing <NUM>, and an arcing space <NUM> connected to the arc discharge opening <NUM> is correspondingly provided in the housing <NUM>. A boss <NUM> is further disposed in the housing <NUM>, and the boss <NUM> is located in the arcing space <NUM>, so that the arcing space <NUM> forms a channel whose size gradually decreases and then increases.

Specifically, in the foregoing manner, in an arc extinguishing process, the arcing space <NUM> forms a channel whose size gradually decreases and then increases. By using a Laval nozzle principle, an arc speed changes with a change of a cross section (as indicated by an arrow direction in <FIG>). A cross section of a front part of a narrow area gradually becomes smaller, and a flow rate gradually increases. In this case, an arc flow rate exceeds a sound speed. In a rear part of the narrow area, an opening gradually becomes larger, a transonic fluid no longer conforms to a rule that a flow rate at a smaller cross section is higher and a flow rate at a larger cross section is smaller. Instead, a flow rate at a larger cross section is higher. Therefore, an overall arc flow rate increases, and an electric arc is discharged out of the arcing space <NUM> as soon as possible, so that the electric arc is extinguished. This helps improve stability of the switch unit <NUM> during use.

As shown in <FIG>, a limiting portion is disposed on the housing <NUM>, and is configured to limit the first pin <NUM> and/or the second pin <NUM>.

In a case not covered by the present invention, when the first stationary contact <NUM> is connected to the first pin <NUM> and the second stationary contact <NUM> is connected to the second pin <NUM>, positions of the first pin <NUM> and the second pin <NUM> may be limited by using the limiting portion on the housing <NUM>. When the second stationary contact <NUM> is connected in another manner, for example, the second stationary contact <NUM> is connected by using the connector <NUM>, only the position of the first pin <NUM> may be limited. It may be understood that, alternatively, only the position of the second pin <NUM> may be limited based on an actual situation during actual use. It may be understood that a position of the auxiliary pin <NUM> may also be limited by using the limiting portion, to improve stability during connection.

Still as shown in <FIG>, <FIG>, the limiting portion includes a limiting groove <NUM> and a clamping protrusion <NUM>. The limiting groove <NUM> and the clamping protrusion <NUM> are separately located on two sides of the housing <NUM> in a stacking direction. The first pin <NUM> and/or the second pin <NUM> pass through the limiting groove <NUM>. When housings <NUM> are stacked, a limiting groove <NUM> and a clamping protrusion <NUM> on adjacent housings <NUM> are clamped, to limit the first pin <NUM> and/or the second pin <NUM>. Alternatively, the limiting portion is a limiting via <NUM>, and the first pin <NUM> and/or the second pin <NUM> pass through the limiting via.

Specifically, when the limiting portion includes the limiting groove <NUM> and the clamping protrusion <NUM>, and the first pin <NUM> and the second pin <NUM> pass through the housing <NUM> and are connected to the circuit board <NUM>, the first pin <NUM> and the second pin <NUM> may separately pass through the limiting groove <NUM>, to limit the first pin <NUM> and the second pin <NUM> by using the limiting groove <NUM>. In addition, when the adjacent housings <NUM> are stacked, the limiting groove <NUM> and the clamping protrusion <NUM> are clamped, to press against the first pin <NUM> and the second pin <NUM>, and prevent the first pin <NUM> and the second pin <NUM> from shaking. As shown in <FIG>, when the limiting portion is the limiting via <NUM>, the first pin <NUM> and/or the second pin <NUM> may pass through the limiting via <NUM>, to limit the first pin <NUM> and/or the second pin <NUM> by using the limiting via <NUM>.

It may be understood that, depending on different connection manners during actual use, only the first pin <NUM> or the second pin <NUM> may be fastened, or all pins may be fastened in the foregoing manner. The foregoing manner is also applicable to the auxiliary pin <NUM>.

As shown in <FIG>, the first extending portion <NUM> and the second extending portion <NUM> separately extend from sides of the housing <NUM>, and the first extending portion <NUM> and the second extending portion <NUM> are separately located on adjacent sides of the housing <NUM> or opposite sides of the housing <NUM>.

Specifically, when a required connection relationship is formed between the switch unit <NUM> and the circuit board <NUM>, the first extending portion <NUM> and the second extending portion <NUM> need to separately extend out from sides of the housing <NUM>. According to an actual connection requirement, the first extending portion <NUM> and the second extending portion <NUM> may separately extend out from adjacent sides of the housing <NUM> or opposite sides of the housing <NUM>, to ensure a required connection.

As shown in <FIG>, an embodiment of this application further provides a switching device <NUM>, including the switch unit <NUM> in the foregoing embodiment. Switch units <NUM> are stacked by using housings <NUM>.

Specifically, in this embodiment of this application, a quantity of stacking layers of switch units <NUM> is not specifically limited, and switch units <NUM> may be flexibly disposed according to an actual requirement. For example, <NUM>, <NUM>, or <NUM> switch units <NUM> may be disposed. Specifically, switch units <NUM> may be properly disposed based on a situation of a line to which the switch units are connected. As shown in <FIG>, when a plurality of switch units <NUM> are stacked, an operation shaft may be connected to a movable contact in each switch unit <NUM>, to control a change of a spatial position of the movable contact, so as to control the switching device <NUM> to be switched on or switched off. In the switching device <NUM> provided in this embodiment of this application, a quantity of manual contacts in a conventional connection manner can be reduced, a quantity of contact connections can be reduced, a connection manner can be simplified, and safety during use can be improved.

As shown in <FIG>, the switching device <NUM> further includes an arc partition board <NUM>. The arc partition board <NUM> includes a plurality of isolation chambers <NUM>. The isolation chambers <NUM> are in a one-to-one correspondence with first pins <NUM> and/or second pins <NUM> of the switch units <NUM>, to block charged particles.

Specifically, a plurality of separators spaced apart are disposed on the arc partition board <NUM>, and an isolation chamber <NUM> is formed between adjacent separators. When charged particles are discharged out of an arc discharge opening <NUM>, the charged particles are blocked by the isolation chamber <NUM>, thereby preventing the charged particles from splashing onto the first pins <NUM> or the second pins <NUM>, and avoiding a short circuit. This helps improve stability of an electrical connection. The isolation chambers <NUM> are in a one-to-one correspondence with the first pins <NUM> and/or the second pins <NUM>, so that the stacked switch units <NUM> can be better protected.

In an optional embodiment of this application, the arc partition board <NUM> and the housing <NUM> are integrally molded, or the arc partition board <NUM> and the housing <NUM> are separately disposed. In this way, flexible disposing may be performed according to an actual requirement during specific use. When an operation space is small, integral molding may be performed. When an operation space is abundant, separate disposing may be performed. When the switching device <NUM> is connected to a circuit board <NUM> through the first pins <NUM> and the second pins <NUM>, the isolation chambers <NUM> can better fit the first pins <NUM> or the second pins <NUM> when a connection position or a connection manner of the first pins <NUM> or the second pins <NUM> changes.

As shown in <FIG>, a first stationary contact <NUM> and a second stationary contact <NUM> are diagonally arranged in the switch unit <NUM>, and stationary contact assemblies <NUM> in adjacent switch units <NUM> are arranged in a staggered manner.

This can improve stability of electrical connection relationships in adjacent housings <NUM>, and avoid mutual interference. In addition, this can also prevent a produced electric arc from splashing onto a first pin <NUM> or a second pin <NUM> disposed on an adjacent housing <NUM>, and also helps provide more operation space, thereby reducing operation difficulty during electrical connection.

It may be understood that, when the movable contact is detached from the first stationary contact <NUM> or the second stationary contact <NUM>, to ensure an arc extending space and increase an arc extinguishing speed by using a permanent magnet <NUM>, relative positions of the permanent magnet <NUM>, the first stationary contact <NUM>, and the second stationary contact <NUM> remain unchanged. In this case, permanent magnets <NUM> in adjacent switch units <NUM> may also be arranged in a staggered manner.

As shown in <FIG>, <FIG>, and <FIG>, a baffle plate <NUM> and a fastener <NUM> connected to a stationary contact assembly <NUM> are disposed on one side of the housing <NUM>, and the fastener <NUM> is located between two baffle plates <NUM> of adjacent housings <NUM>.

Specifically, when the fastener <NUM> is connected to a stationary contact by using a wire <NUM>, the wire <NUM> and the stationary contact assembly <NUM> are connected and fastened, to form an electrical connection path. The fastener <NUM> may be in a form of a screw in combination with a square pad. When the screw is used for fastening, the baffle plate <NUM> may be used for limiting on the square pad, to prevent the pad from rotating along with the screw. This helps better press against the wire <NUM> and improve stability of an electrical connection. In addition, in the foregoing manner, the stationary contact and the fastener <NUM> that are adjacent may be separated, to increase an electric clearance and a creepage distance.

Claim 1:
A switch unit (<NUM>), comprising at least one stationary contact assembly (<NUM>), wherein each stationary contact assembly (<NUM>) comprises a first stationary contact (<NUM>), a second stationary contact (<NUM>), and a first pin (<NUM>) connected to the first stationary contact (<NUM>), and the first pin (<NUM>) is soldered to a circuit board (<NUM>), wherein the stationary contact assembly (<NUM>) further comprises a second pin (<NUM>) connected to the second stationary contact (<NUM>), the first stationary contact (<NUM>) and the first pin (<NUM>) are integrally molded, the second stationary contact (<NUM>) and the second pin (<NUM>) are integrally molded, and the second pin (<NUM>) is soldered to the circuit board (<NUM>), and
the switch unit (<NUM>) is characterised in that it further comprises a housing (<NUM>), the first pin (<NUM>) comprises a first bending portion (<NUM>) connected to the first stationary contact (<NUM>) and a first extending portion (<NUM>) connected to the first bending portion (<NUM>), the first extending portion (<NUM>) and the first stationary contact (<NUM>) are located on different planes, the first pin (<NUM>) is away from an arc discharge opening (<NUM>) of the housing (<NUM>), the second pin (<NUM>) comprises a second bending portion (<NUM>) connected to the second stationary contact (<NUM>) and a second extending portion (<NUM>) connected to the second bending portion (<NUM>), the second extending portion (<NUM>) and the second stationary contact (<NUM>) are located on different planes, and the second pin (<NUM>) is away from the arc discharge opening (<NUM>).