US-12626879-B2 - Circuit breaker tripping mechanism

US12626879B2US 12626879 B2US12626879 B2US 12626879B2US-12626879-B2

Abstract

Embodiments of the present technology include a circuit breaker with a tripping mechanism. The tripping mechanism includes a latch and a latch lever, according to some embodiments. The latch lever may be coupled to a toggle via a joint arm in some embodiments. The latch lever may also be coupled to a change lever via a buckled shackle. In some embodiments, the buckled shackle includes a first section, a second section, and a bend between the first section and the second section.

Inventors

David J. Urech
Sadashiv Pimple
Rahel J. von Arx

Assignees

ROCKWELL AUTOMATION SWITZERLAND GMBH

Dates

Publication Date: 20260512
Application Date: 20231109

Claims (20)

1 . A tripping mechanism comprising: a latch comprising: a pivoting body, a first extension disposed on the pivoting body at a first location, the first extension comprising a latch contact surface, and a second extension disposed on the pivoting body at a second location, the second extension comprising a trip component contact surface, wherein movement of a trip component in contact with the trip component contact surface causes the pivoting body to pivot about a first axis from a first position to a second position; a latch lever comprising: a first end, a second end, and a bend disposed between the first end and the second end, a first rotational joint disposed at the bend and a second rotational joint disposed at the first end and spaced apart from the first rotational joint, a latch lever contact surface disposed at the second end, wherein the latch lever moves between an on position and a trip position, wherein movement of the latch to the second position causes the latch lever to move from the on position to the trip position; and a buckled shackle comprising: a first section comprising a first end coupled to the second rotational joint, a second section comprising a second end coupled to a change lever, wherein the second section is integral with the first section, and a bend having an oblique angle between the first section and the second section, wherein the oblique angle is selected such that a force exerted by the latch lever contact surface on the latch contact surface falls within a sensitivity range when the latch lever is in the on position and the latch is in the first position.
2 . The tripping mechanism of claim 1 , further comprising: a joint arm having a first end and a second end, the first end being rotatably coupled to the first rotational joint and the second end being coupled to a toggle, wherein the toggle is operably coupled to a switch.
3 . The tripping mechanism of claim 1 , wherein the buckled shackle bends around the first rotational joint when the latch lever is in the on position such that at least a portion of the first rotational joint is located between the first end and the second end of the buckled shackle.
4 . The tripping mechanism of claim 1 , wherein the change lever comprises a fixed rotational joint, and wherein the change lever is coupled to a coiled spring that applies a force on the change lever when the latch lever is in the on position.
5 . The tripping mechanism of claim 1 , wherein the sensitivity range is between 6 Newtons and 8 Newtons.
6 . The tripping mechanism of claim 1 , wherein the oblique angle between the first section and the second of the buckled shackle is between 150 degrees and 170 degrees.
7 . The tripping mechanism of claim 1 , wherein a tripping force exerted by the trip component contact surface on the first extension of the latch needed to move the latch from the first position to the second position is approximately 1.4 Newtons.
8 . The tripping mechanism of claim 1 , wherein: the trip component is a thermal trip component, the trip component contact surface of the second extension of the latch is a thermal trip component contact surface, the latch further comprises a third extension disposed on the pivoting body at a third location, the third extension comprises a magnetic trip component contact surface, and movement of a magnetic trip component in contact with the magnetic trip component contact surface causes the pivoting body to pivot about the first axis from the first position to the second position.
9 . The tripping mechanism of claim 1 , further comprising: a third rotational joint disposed in the change lever, wherein: the second end of the buckled shackle is rotatably coupled to the third rotational joint, a line from a rotational center of the second rotational joint to a rotational center of the third rotational joint is aligned with the first rotational joint in a direction perpendicular to a rotational plane of the first rotational joint when the latch lever is in the on position.
10 . The tripping mechanism of claim 9 , wherein when the latch lever is in the on position, no portion of the buckled shackle is aligned with the first rotational joint in a direction perpendicular to the rotational plane of the first rotational joint.
11 . A circuit breaker comprising: a stationary contact disposed in a circuit; a moving contact that moves between a first position in which the moving contact physically contacts the stationary contact and a second position in which the moving contact is separated from the stationary contact; a switch being selectable between an ON state in which the moving contact physically contacts the stationary contact and an OFF state in which the moving contact is separated from the stationary contact; a rotary disk coupled to the switch; and a tripping mechanism coupled to the rotary disk, wherein the tripping mechanism comprises: a latch comprising a first extension having a latch contact surface and a second extension that receives a mechanical indication of a trip condition in the circuit breaker, wherein the latch moves in response to the mechanical indication to initiate a trip response; a latch lever, comprising: a first rotational joint, a second rotational joint spaced apart from the first rotational joint, and a latch lever contact surface that applies a force against the latch contact surface of the latch when the latch lever is in an on position corresponding to the ON state of the switch; and a buckled shackle comprising: a first section comprising a first end coupled to the second rotational joint, a second section comprising a second end coupled to a change lever, wherein the second section is integral with the first section, and a bend having an oblique angle between the first section and the second section, wherein the oblique angle is selected such that a force exerted by the latch lever contact surface on the latch contact surface falls within a sensitivity range when the latch lever is in the on position and the latch is in the first position.
12 . The circuit breaker of claim 11 , further comprising a joint arm having a first end and a second end, the first end being rotatably coupled to the first rotational joint and the second end being coupled to a toggle, wherein the toggle is operably coupled to a switch.
13 . The circuit breaker of claim 11 , wherein the buckled shackle bends around the first rotational joint when the latch lever is in the on position such that at least a portion of the first rotational joint is located between the first end and the second end of the buckled shackle.
14 . The circuit breaker of claim 11 , wherein the change lever comprises a fixed rotational joint, and wherein the change lever is coupled to a coiled spring that applies a force on the change lever when the latch lever is in the on position.
15 . The circuit breaker of claim 11 , wherein the sensitivity range is between 6 Newtons and 8 Newtons.
16 . The circuit breaker of claim 11 , wherein the oblique angle between the first section and the second of the buckled shackle is between 150 degrees and 170 degrees.
17 . The circuit breaker of claim 11 , wherein the second extension comprises a trip component contact surface, and wherein a tripping force exerted by the trip component contact surface on the first extension of the latch needed to move the latch to initiate the trip response is approximately 1.4 Newtons.
18 . The circuit breaker of claim 11 , wherein: the second extension of the latch comprises a thermal trip component contact surface, the latch further comprises a third extension, the third extension comprises a magnetic trip component contact surface, movement of a thermal trip component in contact with the thermal trip component contact surface causes the latch to pivot about an axis from a first position to a second position, and movement of a magnetic trip component in contact with the magnetic component contact surface causes the latch to pivot about the axis from the first position to the second position.
19 . The circuit breaker of claim 11 , further comprising: a third rotational joint disposed in the change lever, wherein: the second end of the buckled shackle is rotatably coupled to the third rotational joint, a line from a rotational center of the second rotational joint to a rotational center of the third rotational joint is aligned with the first rotational joint in a direction perpendicular to a rotational plane of the first rotational joint when the latch lever is in the on position.
20 . The circuit breaker of claim 19 , wherein when the latch lever is in the on position, no portion of the buckled shackle is aligned with the first rotational joint in a direction perpendicular to the rotational plane of the first rotational joint.

Description

INCORPORATIONS The following U.S. Patent Applications, each of which are filed concurrently with the present application, are incorporated by reference herein in their entireties for all purposes: Ser. No. 18/505,948, titled “CIRCUIT BREAKER INTERLOCK MECHANISM,” Ser. No. 18/505,967, titled “CIRCUIT BREAKER LINEAR LEVER AND TRIPPING FORK MECHANISM,” and Ser. No. 18/506,006, titled “CIRCUIT BREAKER COMPENSATION BIMETAL OF A THERMAL TRIPPING MECHANISM.” Each of the applications describe features of a circuit breaker, all of which can be incorporated into a single circuit breaker to obtain the benefit of each of the described features. TECHNICAL FIELD Various embodiments of the present technology generally relate to tripping mechanisms in circuit breakers. More specifically, a tripping mechanism is disclosed that reduces the force needed to cause a trip related to a short circuit or over-current condition while avoiding trips related to physical shocks often experienced in industrial automation environments. BACKGROUND Circuit breakers are electrical switching devices designed to protect electrical circuits from potential damage that can be caused by short circuits or overloads. Circuit breakers may be implemented in industrial environments as components of electrical circuits. When a circuit breaker is turned on, an electrical connection is created by bringing sets of metal contacts into contact with one another to allow the flow of current through the circuit. When the device is turned off, the metal contacts are separated to interrupt the flow of current in the circuit. Circuit breakers may be manually or automatically operated to switch the device between states. Certain challenges have been faced with respect to achieving the appropriate sensitivity of circuit breakers in response to short circuits and overloads. It is with respect to this general technical environment that aspects of the present disclosure have been contemplated. Furthermore, although a general environment is discussed, it should be understood that the described examples should not be limited to the general environment identified in the background. SUMMARY This Overview is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. Various embodiments of this disclosure relate to the mechanics used to stop current flow in a circuit breaker due to a short circuit or over-current condition. The mechanical components include a complex series of components that push a latch when an over-current or short circuit occurs. The latch holds a latch lever in an on position when the circuit breaker is on. Movement of the latch releases the latch lever, and the release of the latch lever causes a series of mechanical movements that separate the contacts of the circuit breaker to halt current flow. The point of contact between the latch and the latch lever sets the sensitivity of the circuit breaker to experiencing a trip. Accordingly, trips can occur due to short circuits and over-current based on the mechanical components of the circuit breaker that are designed to move the latch based on the relevant condition. Further, physical shocks (e.g., drops, bumps, and other physically jarring events) to the circuit breaker can cause a trip to occur if the sensitivity of the circuit breaker is too low. However, setting the sensitivity of the circuit breaker too high by requiring a large force to release the latch lever may make the circuit breaker insensitive to small movements of the components used to trip the circuit breaker based on short circuit and over-current conditions. To combat this potential issue, the described latch, latch lever, buckled shackle, and other movement components of the tripping mechanism are designed to reduce the force needed to trip the circuit breaker due to a short circuit or over-current condition while not creating over-sensitivity to physical jarring of the circuit breaker due to dropping, bumps, and other movement experienced in an industrial automation environment. Some embodiments of the present disclosure include a tripping mechanism including a latch. The latch includes a pivoting body, a first extension disposed on the pivoting body at a first location, the first extension including a latch contact surface, and a second extension disposed on the pivoting body at a second location, the second extension including a trip component contact surface, wherein movement of a trip component in contact with the trip component contact surface causes the pivoting body to pivot about a first axis from a first position to a second position. Some embodiments include a latch lever include: a first end, a second end, and a bend disposed between the first end and the s