Fail safe surge arrester systems
AssigneeTII Industries, Inc.
InventorsCharles A. Roberts, Raymond D. Jones
Life of this patent
Estimating the term…
Abstract
Laminar air gap devices include two overlapping conductive layers separated by a non-metallic insulating layer. The insulating layer is perforated to provide at least one air gap between the conductive layers. The devices are positioned between a line electrode and ground electrode of a gas filled surge arrester and resiliently retained thereon by conductive clips. Non-metallic fusible elements, preferably plastic, are interposed between the clip legs and the associated electrode. The fusible element may also be the insulating layer between the conductive layers.
Claims36
An air gap surge arrester comprising:
- a sealed laminar assembly having first and second layers of electrically conductive metallic material, a portion of said conductive layers being in overlapping relationship, and an intermediate insulating layer interposed between and bonded to said first and said second layers, said insulating layer having a predetermined aperture in the area of overlap between said conductive layers, whereby an air gap is established between said first and said second layers;
- and
- means enveloping said laminar assembly for urging the respective layers of said laminar assembly towards one terminal of a device to be protected from an electric surge, a second terminal of said device being electrically coupled directly to said urging means.
An air gap surge arrester comprising:
- a sealed laminar assembly having first and second layers of electrically conductive metallic material, a portion of said conductive layers being in overlapping relationship, and an intermediate insulating layer interposed between and bonded to said first and said second layers, said insulating layer having a predetermined aperture in the area of overlap between said conductive layers, whereby an air gap is established between said first and said second layers;
- and
- a third layer of conductive material located in longitudinal spaced relationship from said first layer and overlapping at least a portion of said second layer, said intermediate layer defining an air gap between said second and said third layers;
- said first and said third layers extending in a longitudinal direction beyond the ends of said insulating layer, and wherein said insulating layer extends in a transverse direction, perpendicular to said longitudinal direction, beyond peripheral portions of said conductive layers.
A combination fail safe and air gap device for use with a gas filled surge arrester comprising:
- a laminar assembly of first and second metallic electrically conductive layers, said layers being in overlapping relationship, and an intermediate layer of non-metallic fusible material interposed between and in contact with said first and said second layers to prevent short circuiting therebetween except in the presence of a sustained overload causing said fusible material to fuse and yield to permit establishment of a short circuit between said first and said second layers, said intermediate layer having at least one predetermined aperture therein in the area of overlap between said first and said second layers to define an air gap electrode therebetween;
- and
- an electrically conductive member connected to said laminar assembly and adapted for connection with a terminal of said surge arrester.
In a surge arrester assembly having a gas filled surge arrester including at least two electrodes defining an ionization gap and short circuit clamp means biased towards a short circuit connection with said electrodes, the improvement comprising:
- safety means interposed between said one electrode and said short circuit clamp means, said safety means including first and second layers of metallic, electrically conductive material in contact with said clamp means and electrode, respectively, and an intermediate layer of fusible material interposed between said first and second layers, said intermediate layer defining an aperture therein to provide an air gap and operative to prevent said short circuit connection except in the presence of a sustained overload causing said fusible layer to fuse and yield to permit said short circuit means to bias said first layer into short circuit connection with said second layer.
A total fail safe surge arrester assembly having a gas filled surge arrester including at least two electrodes defining an ionization gap, and short circuit clamp means biased toward a short circuit connection with said electrodes, the improvement comprising:
- air gap means interposed between a portion of said short circuiting clamp means and each of said electrodes, said air gap means including a first layer of metallic material in electrical contact with said clamping means and a second layer of metallic material in electrical contact with one of said electrodes and in overlapping relationship with said first layer;
- a layer of insulating material interposed between the overlapping portions of said metallic layers and defining an aperture therein to provide an air gap;
- non-metallic fusible means in thermal contact with said ionization gap and interposed between said clamp means and one of said electrodes to prevent short circuit connection except in the presence of sustained overload causing said fusible means to fuse and yield to permit establishment of said short circuit connection.
Dependencies are inferred from the claim text.