TECHNICAL FIELD OF THE INVENTION
[0001] The invention is related to the operation in electric power distribution lines, particularly
with mechanical devices that enable safety during maintenance or repair work in these
distribution lines.
BACKGROUND OF THE INVENTION
[0002] Among the electric power distribution networks, the usage of circuit breakers is
required to protect the equipment connected to the network from overload. During the
maintenance or repair processes, these circuit breakers should be open to interrupt
the flow of electricity and allow safe intervention of the equipment. This opening
requires, according to the regulations, the use of an arc extinguishing tool (load
break switch) to certify the safety of both the operator and the network equipment:
"19.1 Switching
[0005] Within the technical field of the invention, the most commonly used arc-extinguishing
tool or load break switch is Loadbuster ® which extinguishes the arc for a great number
of devices such as load breaks, short-circuits, potency fuse or limiting fuses.
[0007] "This is what you should look for when selecting a break switch, circuit breaker,
power fuse or limiting fuse to be operated with the Loadbuster:
- There should be a hook at the top end (clamp) of the device, which could hook the
Loadbuster anchor; and a pull-ring at the load break blade or fuse tube of the device
that can be easily locked with the hook for the pullshot of the Loadbuster and stay
engaged with the pull-ring latch.
- The device must be mechanically coordinated with the Loadbuster's operating sequence
such that (a) Hooking the Loadbuster does not cause nor allow the load break blade
or fuse tube to prematurely open and (b) The fixing hook maintains the Loadbuster
effectively anchored until the shot occurs, while (c) allowing quick removal of the
Loadbuster either if the opening stroke is completed or if for any reason the device
being sectioned has been restored after a partial (or incomplete) opening.
- The device must be easy to handle in an effective manner with the Loadbuster from
all practical angles and directions and in all mounting positions for which the device
is designed, keeping to a minimum the mechanical requirements "
[0008] However, in Colombia, many of the circuit breakers currently installed within the
distribution network do not have all these features and in particular, do not have
a fixing hook or latching device (clamp) that allows the coupling the arc extinguisher
to the Loadbuster and thus its opening cannot be made following safety standards.
[0009] The replacement of these fuses with devices including the retention hooks is costly
and involves a great amount of time; thus, such replacement is not viable.
[0010] Consequently, there is within the state of the art the need for an adapting device
that acts as a bridge between the Loadbuster arc extinguisher and the circuit breaker
without retention hooks so that maintenance and repair operations for the equipment
of the network can be performed even in this type of circuit breakers.
[0011] In this sense, the present invention provides a novel adapting device that enables
safe and efficient use of the Loadbuster even in circuit breakers that do not have
retention hooks.
BRIEF SUMMARY OF THE INVENTION
[0012] The invention provides a mechanical device acting as an adapter for the Loadbuster
and enables the opening of circuit breakers that are do not have opening support,
which engages the Loadbuster to the circuit breaker disconnection mechanism.
[0013] Said device of the invention enables the conduction of electricity discharged through
the Loadbuster, leading to the obtainment of efficient arc extinction and therefore,
ensure safe operation.
[0014] Likewise, when the device is installed in the Loadbuster, contact with the power
line occurs by means of a conducting bar that enables the passage of electricity,
and once positioned, the Loadbuster normally attaches to the rim of the cane and may
tug the whole system to disconnect the electrical circuit.
BRIEF DESCRIPTION OF THE FIGURES
[0015]
Figure 1 corresponds to the Loadbuster ® commercial arc extinguisher.
Figure 2 shows a circuit breaker having retention hooks to engage the arc extinguisher.
Figure 3 corresponds to the coupling of the Loadbuster arc extinguisher to said circuit
breaker and operation with the pole for the opening of the circuit breaker.
Figure 4 shows a circuit breaker that has no retention hooks for hooking the arc extinguisher.
Figure 5 corresponds to the adapting device of the invention.
Figure 6 shows a side view of said adapter.
Figure 7 is a top view of the adapting device of the invention.
Figure 8 shows the adapting device of the invention coupled to the Loadbuster arc
extinguisher.
Figure 9 corresponds to the configuration of the adapting device of the invention
coupled to the Loadbuster in use on a pole.
DETAILED DESCRIPTION OF THE INVENTION
[0016] During the operation of electricity distribution networks, it is necessary to cut
the power when performing maintenance or repair works on the equipment connected to
the network. Said equipment has circuit breakers that protect from overload and allow
said power cut for the operation of the network, with the cane-like circuit breakers
being the most commonly used circuit breakers.
[0017] For the opening of the circuit breaker, regulations require that in order to protect
the operator and the equipment, this should be done using an arc extinguisher or a
load break switch, which is commercially known as Loadbuster®.
[0018] This Loadbuster engages a pole and it is manipulated for opening the circuit breaker;
however, said circuit breaker must meet a number of technical features, mainly to
have a fixing hook that allows hooking the Loadbuster.
[0019] This proves to be a drawback, since a large number of circuit breakers currently
installed in the medium voltage network in Colombia do not have such retention hooks
making it impossible to safely open these circuit breakers. Also, given the large
number of such circuit breakers within the network, their replacement with circuit
breakers including said retention hooks due to the high costs and additional operating
times involved.
[0020] In this sense, the present invention provides a novel solution to this problem by
providing an adapting device that acts as a bridge between the circuit breaker and
the Loadbuster arc extinguisher, and enables the safe operation in distribution networks
regardless if the circuit breakers do not have hooks for the Loadbuster coupling.
[0021] Figure 1 shows the Loadbuster ® commercial arc extinguisher that is commonly used
within the circuit breaker opening, which has on its top a hinged latch which engages
with the retaining hooks of the circuit breaker. On the other hand, Figure 2 shows
a circuit breaker suitable for coupling with the Loadbuster arc extinguisher.
[0022] Figure 2 illustrates that the cane-like circuit breaker suitable for coupling with
the Loadbuster has two hooks at the top of the fuse tube, which, as seen in Figure
3, allow coupling with the Loadbuster and, as a result of the force made on the pole,
secure opening of the circuit breaker is achieved.
[0023] Contrary to this, and as shown in Figure 4, a large number of circuit breakers already
installed in the distribution network, although being cane-like, do not have the aforementioned
fastening hooks at the top of the fuse tube which renders impossible the coupling
with the Loadbuster and thus the safe opening of the circuit breaker.
[0024] Figure 5 shows an adapting device of the invention, which is designed to couple in
a firm and secure manner the Loadbuster arc extinguisher and to enable engagement
and opening of the cane.
[0025] Said adapting device of the invention is formed by fastening means which allow the
coupling to the Loadbuster, a movable arm which enables the mechanical displacement
of the adapter and two rods attached to said arm, the first being a contact rod (10)
and the second a guide rod (11).
[0026] As will be evident from Figure 6, in a preferred embodiment of the invention the
retention means comprise a press (1) inserted into a clamp (2) which has a threading
system (3) that allows adjustment.
[0027] These fasteners allow the adapter to be located on right or left position in the
structural part of the Loadbuster's articulated hitch.
[0028] In a preferred embodiment of the invention on the press (1) a strip (8) is fixed
by means of a fastening screw (9), said strip allows the electrical contact between
the adapting device and the "Loadbuster" arc extinguisher equipment.
[0029] Moreover, in a preferred embodiment of the invention, the movable arm (7) is L-shaped
with a degree of tilt between 0° and 120°, which arm is attached to the press (1)
by means of a pin (6) and is adjusted by means of two retaining rings (5).
[0030] Said movable arm (7) has two holes in which the guide rod (11) is first inserted
and the contact rod (10) is then inserted, which rods are fastened to the movable
arm (7) by means of knobs (12) as shown in Figure 7.
[0031] The guide rod (11) allows securing the location of the system to the electric point,
so as to accurately perform the operation with the pole of Loadbuster coupled to the
device of the invention.
[0032] In turn, the contact rod (10) is located in the power line, allowing the passage
of current and thus ensuring the proper functioning of the Loadbuster arc extinguisher.
[0033] In this manner, in a preferred embodiment of the invention the contact rod (10) has
a rounded end, more particularly a semi-sphere has coupled at its outer end that allows
reaching the end point of displacement of the contact rod when opening the circuit
breaker. Also, this end facilitates the adjustment of the contact rod to the guide
rod.
[0034] In a preferred embodiment, the contact bar (10) is made of an electricity conductive
material, for example steel.
[0035] Similarly, the mobile arm (7), the press (1) and the clamp (2) are made of an electricity
conductive material, preferably the mobile arm (7) is made of steel and the press
(1) and clamp (2) are made of aluminum.
[0036] Figure 8 shows the coupling of the adapting device of the invention to the arc extinguisher
Loadbuster. As shown in said figure, the press and the clamp hold the articulated
Loadbuster latch, and this engagement is secured with the threaded system (3).
[0037] Figure 9 shows the adapting device of the invention already coupled to the Loadbuster
on a pole, and the use of such coupled device for opening the cane of a circuit breaker
that has not gripping hooks.
[0038] Once the guide rod (11) and the contact rod (10) are located on the upper rear part
of the circuit breaker, the adapting device of the invention enables manipulation
for opening the cane in a safe manner, in a similar way as would occur if these circuit
breakers would have gripping hooks, also ensuring proper operation of the Loadbuster
arc extinguisher, since once the coupling between the adapting device of the invention
and the Loadbuster is positioned, the latter is normally attached to the rim of the
cane and it is possible to pull the whole system to disconnect the electric circuit.
[0039] Although a particular embodiment of the invention has been disclosed in detail for
illustrative purposes, it will be recognized that variations or modifications to the
embodiment fall within the scope of the present invention.
1. Adapting device that acts as a bridge between an arc extinguisher and a circuit breaker,
said device characterized in that it comprises: fastening means to the arc extinguisher, a movable arm (7), a guide
rod (11) and a contact rod (10); wherein the movable arm (7) supports said guide rod
(11) and contact rod (10), said contact rod (10) makes contact with the power line
and said guide rod (11) allows the location of the adapter to the electrical point
and wherein said adapter is designed to allow safe opening of the circuit breaker
by means of a pole.
2. The device of claim 1 wherein the fastening means comprises a press (1) inserted into
a clamp (2) which has a threading system (3) that allows adjustment.
3. The device of any of the preceding claims, wherein on the press (1) a strip (8) is
fixed by a means of a retention screw (9), wherein said strip allows the electrical
contact between the adapting device and the arc extinguisher equipment.
4. The device of any of the preceding claims, wherein the movable arm (7) is connected
to the press (1) by means of a pin (6) and is adjusted by means of two retaining rings
(5).
5. The device of any of the preceding claims, wherein the movable arm (7) is L-shaped
with a degree of inclination between 0° and 120°.
6. The device of any of the preceding claims, wherein said movable arm (7) has two holes
in which the guide rod (11) and the contact rod (10) are inserted.
7. The device of any of the preceding claims, wherein the guide rod (11) and the contact
rod (10) are fastened to the movable arm (7) by means of knobs (12).
8. The device of any of the preceding claims, wherein the contact bar (10) has a rounded
end.
9. The device of claim 8, wherein the rounded end is a semi sphere.
10. The device of any of the preceding claims, wherein the contact bar (10), the movable
arm (7), the press (1) and the clamp (2) are made of electricity conductive materials.