Line-side power, double break, switched-neutral electronic circuit breaker

Abstract

The circuit breaker has a first fixed contact connected to the line power supply and a second fixed contact connected to the neutral line. The first movable contact connected to the load power terminal is mounted on the movable actuator and juxtaposed with the first fixed contact to form a power circuit when the first movable contact and the first fixed contact are closed. The second movable contact connected to the load neutral terminal is mounted on the movable actuator and juxtaposed with the second fixed contact to form a neutral circuit when the second movable contact and the second fixed contact are closed. The movable actuator moves the first movable contact and the second movable contact in unison in response to actuation of the operating handle or sensing of the tripping time to open the power circuit between the first fixed contact and the first movable contact, and simultaneously opens the neutral circuit between the second fixed contact and the second movable contact.

Description

Technical Field

[0001] The disclosed invention relates to a circuit breaker. Background Art

[0002] Miniature circuit breakers are well known in the prior art. An illustrative circuit breaker design is disclosed in U.S. Patent No. 5,245,302, which belongs to the same patentee as the present application, and the disclosure of which is incorporated herein by reference. As shown in the '302 patent, a basic miniature automatic circuit breaker includes a base and cover, a line power terminal, a load power terminal, and a circuit between the line terminal and the load terminal. The circuit includes fixed contacts and movable contacts fixed to a contact carrier, the movable contacts being movable between a contact open position and a contact closed position to open or close the circuit. The circuit breaker includes an arc interrupt chamber, an operating mechanism for opening and closing the contacts, and a current responsive trip mechanism that releases the operating mechanism to open the contacts in response to a sustained moderate overload or a momentary short circuit.

[0003] Modern miniature circuit breakers incorporate light emitting diodes (LEDs) that enable users to easily identify trip conditions and fault types, such as arc faults or ground faults. In some embodiments, the circuit for the LED is powered from the line power side to ensure that the LED remains illuminated when the circuit breaker is tripped. However, a risk of electric shock occurs if the neutral terminal of the circuit breaker is accidentally disconnected, causing power from the power side to flow through the circuit of the LED and be present at the load neutral terminal of the circuit breaker. Summary of the invention

[0004] In contrast, the present invention provides a simple, safe, practical and easy-to-manufacture miniature circuit breaker that provides power to an electronic board or printed circuit board assembly (PCBA) from the line power side while preventing the risk of electric shock caused by accidental disconnection of the neutral terminal of the circuit breaker. The PCBA can provide power to an LED or power other functions, such as a denial of service solenoid or internal communication hardware, such as a radio transmitter and receiver. According to the present invention, the circuit breaker includes separate contact pairs for a power terminal to a load power terminal circuit path and for a neutral terminal to a load neutral terminal circuit path, and the two contact pairs are simultaneously opened and closed in unison. The PCBA is directly connected across the line power terminal and the neutral terminal, and remains connected when the two contact pairs are opened. However, when both contact pairs are opened, the line power and neutral circuit paths both interrupt the connection with the load power and load neutral terminals to prevent power from the line power side from flowing through the circuit of the PCBA and being present on the load neutral terminal of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1Aand 1B is a circuit diagram of a prior art circuit breaker, which shows a miniature circuit breaker including an electronic board powered by the load side, but when the circuit breaker contacts are opened, the power supply to the LED is interrupted.

[0006] Figure 2A and 2B is a circuit diagram of a prior art circuit breaker, which shows a miniature circuit breaker that includes an electronic board powered by a line power side, but which may pose a risk of electric shock if the neutral terminal of the circuit breaker is accidentally disconnected, thereby allowing power from the line power side to flow through the circuit of the electronic circuit board and exist on the load neutral terminal of the circuit breaker.

[0007] Figure 3A and 3B is a circuit diagram of a circuit breaker according to the present invention, which shows a miniature circuit breaker including an electronic board powered by a line power side. Power is supplied to the electronic board from the line power side while preventing the risk of electric shock due to accidental disconnection of the neutral terminal of the circuit breaker. The circuit breaker includes separate contact pairs for a line power terminal to a load power terminal circuit path and for a neutral terminal to a load neutral terminal circuit path, and the two contact pairs are simultaneously opened and closed in unison. When both contact pairs are open, both the line power and neutral circuit paths interrupt the connection with the load power and load neutral terminals to prevent power from the line power side from flowing through the circuit of the electronic board and being present on the load neutral terminal of the circuit breaker.

[0008] Figure 4A According to the present invention Figure 3A and 3B A front perspective view of a circuit breaker from the upper left, with the contact pairs closed or in the ON position. The circuit breaker includes separate contact pairs for a line power terminal to a load power terminal circuit path and for a neutral terminal to a load neutral terminal circuit path, and the two contact pairs open and close simultaneously and in unison. The circuit of the electronic circuit board is directly connected across the line power terminals and the neutral terminals, and remains connected when the two contact pairs are opened. However, according to the present invention, when both contact pairs are opened, the line power and neutral circuit paths both interrupt the connection with the load power and load neutral terminals to prevent power from the line power side from flowing through the circuit of the electronic board and being present at the load neutral terminal of the circuit breaker.

[0009] Figure 4B According to the present invention Figure 3A and Figure 3B A front perspective view of a circuit breaker from the upper left with the contacts in the open (OPEN) or OFF position.

[0010] Figure 4C According to the present invention Figure 3A and Figure 3B Front perspective view of a circuit breaker with the contacts in the open (OPEN) or closed (OFF) position. DETAILED DESCRIPTION

[0011] Figure 1A and 1B is a circuit diagram of a prior art circuit breaker incorporating an electronic board including light emitting diodes (LEDs) to enable a user to easily identify a trip condition and a fault type, such as an arc fault or a ground fault. The circuit of the electronic board is powered by the load side, but when the circuit breaker contacts are opened, the power supply to the electronic board is interrupted.

[0012] Figure 2A and 2B is a circuit diagram of a prior art circuit breaker, which shows a miniature circuit breaker including an electronic board including a light emitting diode (LED) powered from the line power side to ensure that the LED remains lit when the circuit breaker is tripped. However, a risk of electric shock occurs if the neutral terminal of the circuit breaker is accidentally disconnected, causing power from the power side to flow through the circuit of the electronic board and be present at the load neutral terminal of the circuit breaker.

[0013] Figure 3A and 3B 1 is a circuit diagram of a circuit breaker 100 according to the present invention, which shows a miniature circuit breaker including an electronic board or printed circuit board assembly (PCBA) 140 powered by a line power side 106. The PCBA 140 can provide power to an LED or power other functions, such as a denial of service solenoid or internal communication hardware, such as a radio transmitter and receiver. Power is provided to the PCBA from the line power side while preventing the risk of electric shock caused by accidental disconnection of the neutral terminal 108 of the circuit breaker. The circuit breaker includes a contact pair 112 / 122 for a circuit path from the line power terminal 106 to the load power terminal 152 and a contact pair 110 / 120 for a circuit path from the neutral terminal 108 to the load neutral terminal 150, and the two contact pairs are opened and closed simultaneously and in unison. When both contact pairs 110 / 120 and 112 / 122 are open, the line power circuit path 106 / 152 and the neutral circuit path 108 / 150 are both disconnected from the load power 152 and load neutral 150 terminals to prevent power from the line power side 106 from flowing through the circuit board 140 and being present at the load neutral terminal 150 of the circuit breaker.

[0014] Figure 4A According to the present invention Figure 3A and 3B1 is a front perspective view of a circuit breaker from the upper left, wherein the contact pairs 110 / 120 and 112 / 122 are closed or in the on position. The circuit breaker 100 includes a housing 101 of the circuit breaker, which includes an operating handle 102 and an overcurrent trip mechanism 130 .

[0015] The circuit breaker 100 includes a first stationary contact 112 in the housing that is connected to a line power terminal 106 of the circuit breaker.

[0016] The circuit breaker 100 comprises a second fixed contact 110 in the housing, which is connected to a neutral terminal 108 of the circuit breaker.

[0017] The circuit breaker 100 includes a first movable contact 122 in a housing, which is connected to a load power terminal 152 of the circuit breaker. The first movable contact 122 is mounted on a movable actuator 104 and is juxtaposed with a first fixed contact 112 to form a power circuit between the line power terminal 106 and the load power terminal 152 when the first movable contact 122 and the first fixed contact 112 are closed.

[0018] The circuit breaker 100 includes a second movable contact 120 in a housing, which is connected to a load neutral terminal 150 of the circuit breaker. The second movable contact 120 is mounted on the movable actuator 104 and is juxtaposed with the second fixed contact 110 to form a neutral circuit between the neutral terminal 108 and the load neutral terminal 150 when the second movable contact 120 and the second fixed contact 110 are closed.

[0019] The movable actuator 104 is configured to move the first movable contact 122 and the second movable contact 120 in unison in response to actuation of the operating handle 102 or in response to the overcurrent trip mechanism 130 sensing a trip event, so as to open a power circuit between the corresponding first fixed contact 112 and the first movable contact 122 and simultaneously open a neutral circuit between the second fixed contact 110 and the second movable contact 120, as shown in FIG. Figure 4B As shown. The overcurrent trip mechanism 130 includes a trigger or trip solenoid 111, which releases the trip latch 109 when an overcurrent condition is detected, and the trip latch 109 moves the trip rod 107, which switches the movable actuator 104 to open the two contact pairs 110 / 120 and 112 / 122. The movable actuator 104 is moved by the switching spring 105 in Figure 4A The closed position and Figure 4B The movable actuator 104 also provides an electrical insulation barrier between the first movable contact 122 and the second movable contact 120.

[0020] The circuit breaker 100 includes a load-powered circuit board 142 that writes the fault type of the trip event to the line-powered circuit board 140 through an optocoupler 160 when the triggering or tripping solenoid 111 releases the trip latch 109 to move the trip bar 107 to open the two contact pairs 110 / 120 and 112 / 122. The LED in the line-powered circuit board 140 then displays the fault type. The circuit board 140 can also manage communication hardware, such as a radio transmitter and receiver, to communicate the trip status of the contacts. The circuit board 140 can also manage denial of service hardware, such as circuits and solenoids to move the movable actuator 104 to turn the circuit breaker on and off, for example, in response to commands received by a radio receiver.

[0021] The circuit breaker 100 includes, in a housing 101, an arc chamber 115 (115) having a reduced size surrounding first and second fixed contacts 112 and 110 and first and second movable contacts 122 and 120. Figure 4C ), corresponding to a reduced size air gap between the first movable contact and the first fixed contact and a reduced size air gap between the second movable contact and the second fixed contact. The reduced size air gap is based on dividing the arc current flowing between the first and second fixed contacts and the first and second movable contacts in half.

[0022] Figure 4B According to the present invention Figure 3A and 3B A front perspective view of a circuit breaker from the upper left, wherein the contact pairs 110 / 120 and 112 / 122 are open or in the off position. The operating handle 102 is shown in the off position and the contact pairs are open. The movable actuator 104 is configured to move the first movable contact 122 and the second movable contact 120 in unison in response to actuation of the operating handle 102 or in response to the overcurrent trip mechanism 130 sensing a trip event to open the power circuit between the corresponding first fixed contact 112 and the first movable contact 122 and simultaneously open the neutral circuit between the second fixed contact 110 and the second movable contact 120.

[0023] Figure 4C According to the present invention Figure 3A and Figure 3B as well as Figure 4B A front view of a circuit breaker with the contact pairs open or in the off position. Figure 4C The view in FIG. 1 more clearly indicates the reduced-size arc chamber 115 in the housing and the reduced-size air gap between the movable contact 120 and the fixed contact 110. The reduced-size air gap is based on dividing the arc current flowing between the fixed contacts 110 / 112 and the movable contacts 120 / 122 in half.

[0024] Although specific example embodiments of the present invention have been disclosed, persons skilled in the art will understand that changes may be made to the details described with respect to the specific example embodiments without departing from the spirit and scope of the present invention.

Claims

1. A circuit breaker, comprising: a first fixed contact connected to a line power terminal of the circuit breaker; a second fixed contact connected to a neutral terminal of the circuit breaker; a first movable contact coupled to a load power terminal of the circuit breaker, the first movable contact being juxtaposed with the first fixed contact to form a power circuit between the line power terminal and the load power terminal when the first movable contact is closed with the first fixed contact; a second movable contact connected to a load neutral terminal of the circuit breaker, the second movable contact being juxtaposed with the second fixed contact to form a neutral circuit between the neutral terminal and the load neutral terminal when the second movable contact and the second fixed contact are closed; as well as The first movable contact and the second movable contact are configured to move in unison to open a power circuit between the first fixed contact and the first movable contact and simultaneously open a neutral circuit between the second fixed contact and the second movable contact, The load power supply circuit is a load-powered circuit board configured to write the fault type of the tripping event into the line-powered circuit board through an optical coupler while the first fixed contact and the second fixed contact are opened with the first movable contact and the second movable contact; as well as The display is a light emitting diode (LED) that is directly connected across the line power terminals and the neutral terminals and is configured to display the type of fault.

2. The circuit breaker according to claim 1, further comprising: A housing of the circuit breaker, which includes an operating handle and an overcurrent tripping mechanism; and The movable actuator is configured to move the first movable contact and the second movable contact in response to actuation of the operating handle or sensing of a trip event by the overcurrent trip mechanism.

3. The circuit breaker according to claim 2, further comprising: A reduced-size arc chamber in a housing surrounding the first fixed contact and the second fixed contact and the first movable contact and the second movable contact, corresponding to a reduced-size air gap between the first movable contact and the first fixed contact and a reduced-size air gap between the second movable contact and the second fixed contact, the reduced-size air gap being based on dividing the arc current between the first fixed contact and the second fixed contact and the first movable contact and the second movable contact.

4. The circuit breaker according to claim 1, further comprising: a line powered circuit board including at least one of a light emitting diode (LED), denial of service hardware, or communication hardware connected directly across a line power terminal and a neutral terminal, the at least one of the light emitting diode (LED), denial of service hardware, or communication hardware remaining connected when the first fixed contact and the second fixed contact are open with the first movable contact and the second movable contact; Thereby, the circuit board is powered from the line power side while preventing the risk of electric shock due to accidental disconnection of the neutral terminal of the circuit breaker.

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