Molded-case circuit breaker with main contact interlock feature

Patent metadata

Field	Value
Publication number	US-10497526-B2
Application number	US-201715841674-A
Country	US
Kind code	B2
Filing date	Dec 14, 2017
Priority date	Feb 28, 2017
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

The present invention relates to a molded-case circuit breaker with a main contact interlock feature preventing improper operation of a tripping mechanism that trips main contacts when the main contacts fuse together. The circuit breaker includes a handle that transfers the user's operational force; a switch lever rotatably mounted on a side plate and connected to the handle, with a pressure portion formed on a part of it; a shaft link, one end of which is rotatably mounted on a shaft pin, that has a contact region on the top; a trip lever rotatably mounted on the side plate, one end of which is slidably connected to the shaft link, and the other end of which is connected to a nail of a tripping mechanism, wherein, if the pressure portion makes contact with the contact region, the trip lever rotates the nail.

First claim

What is claimed is:

1. A molded-case circuit breaker with a main contact position interlock feature, the circuit breaker comprising:
a handle that transfers a user's operational force;
a switch lever rotatably mounted on a side plate and connected to the handle, with a pressure portion formed on a part of the switch lever;
a shaft link, one end of which is rotatably mounted on a shaft pin, that has a contact region on a top portion of the shaft link;
a trip lever rotatably mounted on the side plate, a first end of which is slidably connected to the shaft link, and a second end of which is connected to a nail of a tripping mechanism,
wherein, when the pressure portion makes contact with the contact region, the trip lever rotates the nail,
wherein an arc-like slit is formed through the shaft link, and a protrusion is formed at the first end of the trip lever to be slidably inserted into the slit, and
wherein the protrusion makes contact at a point on an upper end of the slit when in an off state, and the protrusion makes contact with a point on a lower end of the slit when in a fused state.

2. The circuit breaker of claim 1 , wherein the slit is divided into a first part extending from the upper end of the slit to a first point where the protrusion is in an on state, and a second part extending from the first point to the lower end point, and the second part slopes at an angle less than 45 degrees with respect to a contact surface where the contact region makes contact with the pressure portion.

3. The circuit breaker of claim 2 , wherein the first part bulges toward a left or right direction, and the second part bulges toward the left direction.

4. The circuit breaker of claim 1 , wherein the trip lever has a rotating shaft hole at a center of the trip lever, with a first arm at a first side of the trip lever and a second arm at a second side of the trip lever.

5. The circuit breaker of claim 1 , wherein the trip lever has a torsion spring that exerts a clockwise torque on the trip lever.

6. The circuit breaker of claim 5 , wherein the first arm has a spring support that supports one end of the torsion spring.

7. The circuit breaker of claim 4 , wherein a supporting piece is formed on a part of a base mold, and the second arm has a stopper that makes contact with the supporting piece.

Assignees

• Lsis Co Ltd

Inventors

• Cho Seongyeol

Classifications

• H01H71/525

  comprising a toggle between cradle and contact arm and mechanism spring acting between handle and toggle knee · CPC title

• H01H71/501 Primary

  Means for breaking welded contacts; Indicating contact welding or other malfunction of the circuit breaker · CPC title

• H01H1/2041

  Rotating bridge · CPC title

• H01H71/1054 Primary

  Means for avoiding unauthorised release · CPC title

• H01H71/128 Primary

  Manual release or trip mechanisms, e.g. for test purposes (two similar push buttons for closing or resetting and opening or tripping H01H71/58; test switches for earth fault circuit breakers H01H83/04) · CPC title