Patent Application
20100264004
1. Field
The subject matter described herein relates generally to circuit breakers and, more particularly, to mounting accessory devices to circuit breakers.
2. Related Art
It is known in the art to provide molded case circuit breakers for electrical systems. The circuit breaker is operative to disengage the electrical system under certain operating conditions. The use of accessories such as, for exemplary purposes only, motor operators to allow the motor-assisted operation of electrical circuit breakers is well known. The motor operator allows the circuit breaker to be operated remotely and to be opened, closed or reset after tripping of the circuit breaker.
The motor operator is typically secured to the top of a circuit breaker housing. A lever within the motor operator mechanically interacts with a circuit breaker operating handle, which extends from the circuit breaker housing. The lever is operatively connected to a motor within the motor operator. The motor drives the lever, which, in turn, moves the operating handle to operate the circuit breaker. The operating handle is moved between “on”, “off”, and “reset” positions, depending on the rotational direction of the motor.
A plurality of buttons external to the motor operator controls electrical current to the motor. The rotational direction of the motor is changed depending on which of these buttons is selected by operating personnel. Thus, the operating personnel can select one button to place the operating handle in the “on” position, and another button to place the operating handle in the “off” or “reset” positions.
When the handle is moved to the “on” position, electrical contacts within the circuit breaker are brought into contact with each other, allowing electrical current to flow through the circuit breaker. When the handle is moved to the “off” position, the electrical contacts are separated, stopping the flow of electrical current through the circuit breaker. When the handle is moved to the “reset” position, an operating mechanism within the circuit breaker is reset, as is necessary after the operating mechanism has tripped in response to an overcurrent condition in the electrical circuit being protected by the circuit breaker.
Due to the mounting of the motor operator onto the case of the circuit breaker, the motor operator may generate large amounts of mechanical shock during operation, which may adversely effect the performance of the circuit breaker or accessory device internal to or peripheral to the circuit breaker. It would be desirable to mount accessories such as for example, motor operators, to a circuit breaker such that mechanical shock generated by the accessories is minimized.
In accordance with one exemplary embodiment, an apparatus for connecting an accessory device to a circuit breaker to attenuate mechanical force generated by the accessory device is described. The apparatus includes a base having one or more projections configured to engage the circuit breaker to form a rigid connection to the circuit breaker, and one or more apertures configured for engagement with the accessory device to form a rigid connection to the accessory device.
In accordance with another exemplary embodiment, an assembly for connecting an accessory device to a circuit breaker includes an accessory base plate and an apparatus. The apparatus has a base having one or more projections configured to engage the circuit breaker to form a rigid connection to the circuit breaker, and one or more apertures configured for engagement with the accessory base plate to form a rigid connection to the accessory base plate.
In accordance with still another exemplary embodiment, a circuit breaker assembly includes a circuit breaker, an accessory device, and an apparatus. The apparatus has a base having one or more projections configured to engage the circuit breaker to form a rigid connection to the circuit breaker, and one or more apertures configured for engagement with the accessory device to form a rigid connection to the accessory device.
In accordance with yet another exemplary embodiment, a method for attenuating mechanical force induced in a circuit breaker by an accessory device includes engaging the circuit breaker with an apparatus to form a rigid connection to the circuit breaker, and engaging the accessory device with the apparatus to form a rigid connection to the accessory device. The rigid connections to the circuit breaker and the accessory device operate to attenuate mechanical force generated by the accessory device.
The following detailed description is made with reference to the accompanying drawings, in which:
In one exemplary embodiment, referring to
The exemplary embodiments may provide a reliable arrangement of mounting an accessory device 100 to a circuit breaker 120 in such a way that the accessory device 100 and circuit breaker 120 work in tandem to attenuate or reduce any mechanical shock or force generated by the circuit breaker accessory device. The mounting arrangement operates to avoid transferring the mechanical shock or force to other portions of the circuit breaker 120 or other portions of the accessory device 100. In one aspect, the exemplary embodiments may advantageously avoid malfunctions in an electrical system or disruption of a power supply of the electrical system due to inadvertent tripping of peripheral circuit breaker devices due to mechanical shock or force generated by the accessory device 100.
In one exemplary embodiment, the accessory device 100 may be a motor operator that allows for the remote operation of the circuit breaker 120. However, in alternate embodiments, the exemplary embodiments may be equally applied to any suitable circuit breaker accessory device.
Still referring to
The base plate 110 of the circuit breaker accessory device may be rigidly mounted to the top portion 120A of the circuit breaker 120 in any suitable manner. In one exemplary embodiment, the base plate 110 may be mounted to the top portion 120A by, for example, any suitable number of fasteners 201-206, such as screws.
In another exemplary embodiment one or more first fasteners 201, 202 may retain the accessory base plate 110 and engage an apparatus 300 in the form of a breaker mechanism plate (
Referring to
Referring also to
The mounting and securement of the accessory device 100 to the circuit breaker 120 (
The connection formed between the accessory base plate 110 and the apparatus 300 is such that any mechanical shock or mechanical force generated by the operation of accessory device 100 is substantially reduced or attenuated upon generation of the mechanical shock or mechanical force by the accessory device 100. In this exemplary embodiment, the coupling formed between the accessory base plate 110 and the apparatus 300 is such that the accessory device 110 and the circuit breaker 120 work in tandem to reduce or attenuate any mechanical shock or force generated by, for example, the accessory device to a minimum level. In addition, the mounting arrangement operates to “ground” the mechanical shock or force in order to minimize any transfer of the mechanical shock or force to other portions of the circuit breaker 120 or other portions of the accessory device 100. Reducing or minimizing the mechanical shock or force may generally avoid a malfunction in any electrical system protected by circuit breaker 120 or disruption of a power supply in the protected electrical system due to inadvertent tripping of the peripheral devices due to the mechanical shock or force acting on the circuit breaker 120 or any peripheral accessories of the circuit breaker.
At least one of the second set of fasteners 205, 206 (
While exemplary embodiments have been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the embodiments are not limited to those disclosed herein. Rather, the embodiments described are intended to cover all of the various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
