Electricity: circuit makers and breakers – Contact moved by sudden release of stored energy
Reexamination Certificate
1997-12-31
2001-01-16
Luebke, Renee (Department: 2833)
Electricity: circuit makers and breakers
Contact moved by sudden release of stored energy,
Reexamination Certificate
active
06175089
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a load switch, and ore particularly to an improved multi-position automatic switching actuator for a load switch which makes it possible to appropriately switch one contact point to another and carry out a 3-position (open-close-earth) switch control and multi-position switch control by employing a single actuator.
2. Description of Related Art
In general, a load switch employs a power distribution system. The power distribution system includes an overhead power distribution line and a subterranean power distribution line, and allows electrical power supplied from a first substation to provide power to power receiving devices for power consumers. Such a load switch may be used to partition and branch power lines for the subterranean power lines.
As shown in
FIG. 1
, the load switch according to the conventional art includes a main body
1
, four switching actuators
100
respectively disposed at upper portions of the main body
1
for making a movable contact move, and a plurality of three-phase main bushes
2
positioned at lower portions of the switching actuators
100
for receiving power from a first substation and selectively supplying or interrupting power to power receiving facilities of respective electric loads under the control of the switching actuators
100
.
In a conventional load switch, the switching actuator
100
actuates respective movable contacts for the power received from one of the main bushes
2
depending upon its demand, thereby either supplying the power to another of the main bushes
2
or to respective power consumers, or interrupting the power supply.
The switching actuator for the conventional load switch will now be described.
As shown in
FIGS. 2 and 5B
, the switching actuator for the conventional load switch, known as a toggle-type control device, carries out a two-position contact switching. The switching actuator includes: a base plate
120
; a driving shaft unit
130
disposed at a central portion behind the base plate
120
and having a driving shaft
132
protrudingly formed from a marginal end surface thereof; a subordinate driving shaft link unit
140
having a through hole
142
formed through an end portion thereof through which the driving shaft
132
extends so as to be coupled with the driving shaft unit
130
; a spring
150
having a left end portion
151
hooked on a hook protrusion
134
extending backwardly from another end portion of the driving shaft unit
130
, and another end portion
152
hooked on a protrusion
144
extending from an end portion of the subordinate driving shaft link unit
140
; a central shaft unit
160
disposed below a portion at which the driving shaft unit
130
and the subordinate driving shaft link unit
140
are coupled with each other, and an end portion of which is movably engaged to a link
143
; and a control handle
110
disposed at a front portion of the base plate
120
and having an insertion protrusion (not shown) formed at a center so as to be engaged to the driving shaft
132
.
The base plate
120
includes a through hole (not shown) formed in a center thereof, and arc openings
121
for controlling a rotation of the driving shaft
132
are formed at left and right sides of the through hole (not shown).
As shown in
FIGS. 4A and 4B
, the driving shaft unit
130
includes: a stable arm
131
; the driving shaft
132
extending from an end portion of the stable arm
131
, wherein an insertion opening (not shown) is formed in an end portion of the driving-shaft
132
so that the control handle
110
is engaged in the insertion opening (not shown); a limit protrusion
133
protruding from the stable arm
131
to limit the rotation of the driving shaft unit
130
; and the hook protrusion
134
extending from an end portion of the stable arm
131
so as to rotate in correspondence to the rotation of the driving shaft
132
.
In the above constituted driving shaft unit
130
, the hook protrusion
134
is hooked on the one end portion
151
of the spring
150
, and the limit protrusion
133
is inserted into the arc opening
121
formed in the base plate
120
, so that the rotation of the driving shaft unit
130
is limited accordingly.
As shown in
FIGS. 5A and 5B
, the subordinate driving shaft link unit
140
includes: a pair of stable pads
141
; the link
143
provided between the pair of stable pads
141
; the through hole
142
formed at the end of the stable pads
141
and having the driving shaft
132
extending therethrough; the hook protrusion
144
extending from another end portion of the stable pads
141
and being moved by the elasticity of the spring
150
; and a limit protrusion
145
extending from a portion of the stable pads
141
.
Also, in a center of each of the stable pads
141
, an insertion hole (not shown) is formed which receives an insertion protrusion
146
therethrough.
In the subordinate driving shaft link unit
140
, the hook protrusion
144
is hooked on the other end portion
152
of the spring
150
, and the limit protrusion
145
is inserted into the other arc opening
121
formed in the base plate
120
to limit the rotation of the subordinate driving shaft link unit
140
.
The link
143
includes insertion openings
143
a
formed in each end portion thereof. The insertion protrusion
146
of the stable pads
141
and an insertion protrusion
163
extending from a portion of the central shaft unit
160
are correspondingly inserted into the respective insertion openings
143
a
, whereby the rotation force of the subordinate driving shaft link unit
140
is transferred to the central shaft unit
160
.
The central shaft unit
160
, as shown in
FIG. 2
, includes a central shaft
162
, and a stable arm
161
having an insertion protrusion
163
. The central shaft
162
extends from another end portion of the unit
160
.
The operational steps of a conventional two-position switching actuator for a load switch according to the manual control method will now be described with reference to the accompanying drawings.
As shown in
FIGS. 2
,
3
and
6
-
8
, when the control handle
110
is gradually rotated in the clockwise direction, the rotational force of the control handle
110
is transferred to the driving shaft unit
130
through the driving shaft
132
connected thereto. As a result, driving shaft unit
130
gradually rotates in the clockwise direction.
When the driving shaft unit
130
rotates in the clockwise direction, the hook protrusion
134
formed at the end portion of the driving shaft unit
130
rotates gradually in the clockwise rotation, thereby causing tension at the spring
150
hooked on the hook protrusion
134
(FIG.
7
).
When the limit protrusion
133
of the driving shaft unit
130
reaches an end portion of one arc opening
121
of the base plate
120
after the continuous rotation of the driving shaft unit
130
, the hook protrusion
144
extending from the end portion of the rear surface of the suborinate driving shaft link unit
140
instantly makes a counter-clockwise rotation in accordance with the elastic restoration force of the spring
150
(FIG.
8
), whereby the subordinate driving shaft unit
140
rotates counter-clockwise.
When the subordinate driving shaft link unit
140
rotates in the counter-clockwise direction, the central shaft
162
connected to the link
143
makes a counter-clockwise rotation, thereby switching a contact position.
However, although such a two-position (open-close) switch operation may be completely carried out using the conventional switching actuator, more than two switching actuators are needed in order to perform other switching operations, such as a 3-position (open-close-earth) or a 4-position (open-close-open-close) contact switching operation.
Consequently, the conventional two-position contact switching actuator is inconvenient to use and the applicability of the conventional switching actuator is limited.
In addition, since an operator has to directly operate the load switch to control the conventional switc
LG Industrial Systems Co. Ltd.
Luebke Renee
LandOfFree
Multi-position automatic switching actuator for load switch does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-position automatic switching actuator for load switch, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-position automatic switching actuator for load switch will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455097