GB2496062A - Electronic equipment casing - Google Patents
Electronic equipment casing Download PDFInfo
- Publication number
- GB2496062A GB2496062A GB1221667.7A GB201221667A GB2496062A GB 2496062 A GB2496062 A GB 2496062A GB 201221667 A GB201221667 A GB 201221667A GB 2496062 A GB2496062 A GB 2496062A
- Authority
- GB
- United Kingdom
- Prior art keywords
- casing
- elastomeric coating
- precursor materials
- coating
- text
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000011248 coating agent Substances 0.000 claims abstract description 40
- 238000000576 coating method Methods 0.000 claims abstract description 40
- 239000004814 polyurethane Substances 0.000 claims abstract description 11
- 239000000203 mixture Substances 0.000 claims abstract description 8
- 229920002635 polyurethane Polymers 0.000 claims abstract description 8
- 238000005507 spraying Methods 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 claims description 21
- 229920001971 elastomer Polymers 0.000 claims description 19
- 239000000806 elastomer Substances 0.000 claims description 19
- 239000002243 precursor Substances 0.000 claims description 19
- 229920002396 Polyurea Polymers 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 9
- 238000000151 deposition Methods 0.000 claims description 4
- 229920003226 polyurethane urea Polymers 0.000 claims 3
- 229920000162 poly(ureaurethane) Polymers 0.000 abstract description 2
- 239000013536 elastomeric material Substances 0.000 abstract 1
- 230000011664 signaling Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 239000004433 Thermoplastic polyurethane Substances 0.000 description 3
- 229920001169 thermoplastic Polymers 0.000 description 3
- 229920002803 thermoplastic polyurethane Polymers 0.000 description 3
- 239000004416 thermosoftening plastic Substances 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 239000012948 isocyanate Substances 0.000 description 2
- 150000002513 isocyanates Chemical class 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920000768 polyamine Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0254—After-treatment
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/02—Casings
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K5/00—Casings, cabinets or drawers for electric apparatus
- H05K5/02—Details
- H05K5/0247—Electrical details of casings, e.g. terminals, passages for cables or wiring
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/14—Mounting supporting structure in casing or on frame or rack
- H05K7/1422—Printed circuit boards receptacles, e.g. stacked structures, electronic circuit modules or box like frames
- H05K7/1427—Housings
- H05K7/1432—Housings specially adapted for power drive units or power converters
- H05K7/14325—Housings specially adapted for power drive units or power converters for cabinets or racks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/02—Processes for applying liquids or other fluent materials performed by spraying
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D2503/00—Polyurethanes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/22—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to internal surfaces, e.g. of tubes
- B05D7/227—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to internal surfaces, e.g. of tubes of containers, cans or the like
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Plasma & Fusion (AREA)
- Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Organic Insulating Materials (AREA)
- Polyurethanes Or Polyureas (AREA)
- Paints Or Removers (AREA)
Abstract
A power convertor casing is covered with an elastomeric coating which electrically insulates the casing. The elastomeric material may comprise a 1:1 mixture of polyurea and polyurethane which is applied by spray coating. The coating provides a waterproof weather resistant insulating casing which can be used to house a transformer in an outdoor environment. The coating can completely insulate a metallic casing so that no earth connection for the casing needs to be provided.
Description
CASINGS
The present invention relates to casings and is especially, although not exclusively, related to an electrically isolated casing for housing a power convertor such as a s transformer The present invention also relates to a coating for electrically isolating casings, e.g. casings for power convertors.
Rail industry standards are presently undergoing change so as to challenge existing norms and practices in respect of railway signalling power design. The principal driver io for such change is the need to reduce capital and operational expenditure. Indeed, Network Rail has developed a revolutionary approach to signalling projects that will save 33 % of the copper it would previously have used to distribute power. To date, power for signals has been sent down three-core armoured cables, including an earth wire! along with the two live wires: this is known as Class 1 distribution. Recent its development has seen the implementation of a Class 2 distribution system which utilises two-core cable, thus reducing weight, transport costs, laying costs and the cost of the cable itself.
Transformers for railway signalling are known to be provided within steel casings to protect the transformer against theft and/or to protect the transformer against weathering.
Prior art casings are provided with cable to locally earth the casing so as to protect against electric shock. The earth cables are typically armoured sheaths encapsulating copper wire.
There is a cost saving to be had by reducing the amount of copper used on the casings. Therefore, it is desirable to dispense with the earth cables of the casings. In fact, this may become an industry requirement.
s It is an object of the present invention to provide improved casings which overcome, or at least substantially reduce, the disadvantages associated with the known casings described above.
Accordingly, a first aspect of the invention provides a casing, e.g. a casing for housing to a power convertor, wherein the casing is at least partially covered with an elastomeric coating for electrically isolating the casing.
Preferably, the entire outer surface area of the casing is coated with the elastomeric coating.
The entire inner surface area of the casing may be coated with the elastomeric coating.
Preferably, the elastomeric coating has a thickness of from approximately 0.5 mm to approximately 5 mm, e.g. 0.5 mm to 3 mm, e.g. 0.75 mm to 2 mm, say approximately 1.5mm.
Preferably, the elastomeric coating comprises polyurethane (e.g. thermoplastic polyurethane) and/or polyurea (e.g. thermoplastic polyurea).
The inventor has discovered that such a coating gives the casing complete electrical isolation. Therefore, it is possible to dispense with the earth cable from the casing to satisfy the requisite Class 2 criteria.
In a second aspect the invention provides a method of electrically insulating a casing, e.g. a casing for housing a power convertor, which method comprises heating elastomer precursor materials; depositing the heated elastomer precursor materials to at least partially coat the casing; and curing the heated elastomer precursor materials s to form an elastomeric coating.
Preferably, the method comprises the step of coating the entire outer surface area of the casing with the elastomeric coating.
to Preferably, the method comprises the step of coating the entire inner surface area of the casing with the elastomeric coating.
Preferably, the step of heating the elastomer precursor materials comprises heating the elastomer precursor materials to approximately 90°C or above, for example heating the is elastomer precursor materials to approximately 90°C to approximately 160°C, e.g. approximately 100°C to approximately 150°C, e.g. approximately 110°C to approximately 140°C, e.g. approximately 120°C to approximately 140°C, say approximately 13ODC.
Preferably, the step of depositing the heated elastomer precursor materials comprises spraying the heated elastomer precursor materials onto the casing, such as by spraying the heated elastomer precursor materials from a heatable nozzle onto the casing.
Preferably, the elastomeric coating comprises polyurethane, (e.g. thermoplastic polyurethane) or polyurea (e.g. thermoplastic polyurea) or mixtures thereof.
Preferably, when a mixture is used, the elastomeric coating comprises a 1:1 ratio of polyurethane to polyurea.
In a third aspect the invention provides for the use of an elastomeric coating to s electrically insulate a casing, ag. a casing for a power convertor.
Preferably, the elastomeric coating comprises polyurethane, (e.g. thermoplastic polyurethane) or polyurea (e.g. thermoplastic polyurea) or mixtures thereof.
to In a further aspect the invention provides an article, wherein the article is at least partially covered with an elastomeric coating for electrically isolating the article.
Preferably, the article comprises at least one electronic and/or electrical component located therein.
Preferably, the article may be selected from any one of a power convertor (such as a transformer), street furniture (such as a lamp post), a street light distribution system; a car charging point or a marine switchgear assembly.
In order that the invention may be more fully understood, it will now be described by way of example only and with reference to the accompanying drawings, whereby: Figure 1 shows a perspective view of a casing according to the invention; and Figure 2 shows a plan view of the casing of Figure 1 with the top portion removed.
As shown in Figures 1 and 2, a casing, indicated generally at 1, comprises a base 10, four walls ila-d, and atop portion 12.
The casing 1 is formed from metal (such as mild steel) or any other suitable material.
S
Walls lib and lid are provided with vents i3so as to permit heat to transfer from the casing 1 to its surroundings. Walls llb and lid are also provided with handles 14 50 as to provide means to allow a user to carry and/or reposition the casing 1.
to Wall ha is provided with a removable wall section 15. The wall section 15 is fitted to the casing 1 by first engaging the lowermost pad of the wall section 15 within the wall ha and then rotating the wall section 15 towards the casing 1. A pair of nuts 16 are used to secure the wall section 15 to the casing 1. The top portion i2 is similarly removable. The top portion 12 is securable to the casing 1 by nuts 17.
The nuts 16, 17 are non-electrically conductive nuts typically comprised of a plastics material such as PTFE, although other insulating materials may be envisaged.
As shown in Figure 2, the casing 1 is fitted with a power convertor 20. The power convertor 20 is typically a single or three phase railway signalling transformer such as those well known in the art.
The casing 1 is provided with an elastomeric coating. The elastomeric coating is provided on the entire inside and outside surfaces of the casing 1.
The elastomeric coating is formed from a two-component polyurea/polyurethane hybrid spray elastomer system. The polyurea is the reaction product of an isocyanate prepolymer and a resin blend component (such as polyamine). The polyurethane is the reaction product of an isocyanate prepolymer and poiyoi. An example of a suitable coating is the product LINE-X XS-100 RESIN which is supplied by LINE-X PROTECTIVE COATINGS LTD, LINE-X HOUSE, BRANNAM CRESCENT, s ROUNDSWELL BUSINESS PARK, BARNSTAPLE, NORTH DEVON, EX3I 3Tli The inventor has discovered that the elastomeric coating electrically isolates the casing 1, meaning that the power convertor 20 inside the casing 1 is completely isolated from its surroundings. Therefore it is near to impossible to get an electric shock from to touching the casing 1 and therefore the earth cable can be omitted. An additional advantage is that elastomeric coating protects the casing 1 from weathering.
Claims (1)
- <claim-text>CLAIMS1. A casing, e.g. a casing for housing a power convertor, wherein the casing is at least partially covered with an elastomeric coating for electrically isolating the casing.S</claim-text> <claim-text>2. A casing according to claim 1, wherein the entire outer surface area of the casing is coated with the elastomeric coating.</claim-text> <claim-text>3. A casing according to claim 1 or 2, wherein the entire inner surface area of the to casing is coated with the elastorneric coating.</claim-text> <claim-text>4. A casing according to any preceding claim, wherein the elastomeric coating has a thickness of from approximately 0.5mm to approximately 5 mm.as 5. A casing according to any preceding claim, wherein the elastomeric coating comprises polyurethane or polyurea or mixtures thereof.6. A casing according to claim 5, wherein the elastomeric coating comprises a 1:1 ratio of polyurethane to polyurea.7. A method of electrically insulating a casing, e.g. a casing for housing a power convertor, which method comprises heating elastomer precursor materials; depositing the heated elastomer precursor materials to at least partially coat the casing; and curing the heated elastomer precursor materials to form an elastomeric coating.8. A method according to claim 7 further comprising the step ot coating the entire outer surface area of the casing with the elastomeric coating.S9. A method according to claim 7 or 8 further comprising the step of coating the entire inner surface area of the casing with the elastomeric coating.s 10. A method according to any one of claims 7 to 9, wherein the step of heating the elastomer precursor materials comprises heating the elastomer precursor materials to above 90°C.11. A method according to any one of claims 7 to 10, wherein the step of depositing the to heated elastomer precursor materials comprises spraying the heated elastomer precursor materials onto the casing, such as by spraying the heated elastomer precursor materials from a heatable nozzle onto the casing.12. A method according to any one of claims 7 to 11, wherein the step of heating the as elastomer precursor materials comprises heating polyurethane or polyurea precursor materials or mixtures thereof.13. Use of an elastomeric coating to electrically insulate a casing, e.g. a casing for a power convertor.14. Use of an elastomeric coating according to claim 13, wherein the elastomeric coating comprises polyurethane or polyurea or mixtures thereof.15. A casing substantially as hereinbefore described with reference to the accompanying figures.16. A method substantially as hereinbefore described.17. Use of an elastomeric coatin9 substantially as hereinbetore described.</claim-text>
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1221667.7A GB2496062B (en) | 2012-12-03 | 2012-12-03 | Casings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1221667.7A GB2496062B (en) | 2012-12-03 | 2012-12-03 | Casings |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2496062A true GB2496062A (en) | 2013-05-01 |
| GB2496062B GB2496062B (en) | 2014-10-29 |
Family
ID=48046163
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1221667.7A Active GB2496062B (en) | 2012-12-03 | 2012-12-03 | Casings |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2496062B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016065143A3 (en) * | 2014-10-24 | 2016-06-02 | Abb Technology Ag | A hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| WO2018136158A1 (en) | 2017-01-20 | 2018-07-26 | Yaskawa America, Inc. | Method and system for environmental sealing of electrical enclosures |
| US11914057B2 (en) | 2015-10-07 | 2024-02-27 | Hitachi Energy Ltd | System for detecting an object approaching and/or impacting electrical equipment |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3644658A (en) * | 1970-06-04 | 1972-02-22 | Albert J Kuti | Encased fluid filled transformer |
| US20040227437A1 (en) * | 2003-05-12 | 2004-11-18 | Newton Kenneth W. | Enclosure for electronic devices |
-
2012
- 2012-12-03 GB GB1221667.7A patent/GB2496062B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3644658A (en) * | 1970-06-04 | 1972-02-22 | Albert J Kuti | Encased fluid filled transformer |
| US20040227437A1 (en) * | 2003-05-12 | 2004-11-18 | Newton Kenneth W. | Enclosure for electronic devices |
Non-Patent Citations (1)
| Title |
|---|
| http://www.linex.com/pages/2010/about_linex.php 18/3/2013 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016065143A3 (en) * | 2014-10-24 | 2016-06-02 | Abb Technology Ag | A hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| CN107250709A (en) * | 2014-10-24 | 2017-10-13 | Abb瑞士股份有限公司 | Reinforce sensing apparatus and for protecting sensing apparatus from the system and method for catastrophic event |
| US10431375B2 (en) | 2014-10-24 | 2019-10-01 | Abb Schweiz Ag | Hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| CN107250709B (en) * | 2014-10-24 | 2019-11-15 | Abb瑞士股份有限公司 | Reinforce sensing apparatus and for protecting sensing apparatus from the system and method for catastrophic event |
| US10679787B2 (en) | 2014-10-24 | 2020-06-09 | Abb Schweiz Ag | Hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| US10832859B2 (en) | 2014-10-24 | 2020-11-10 | Abb Schweiz Ag | Hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| EP3210217B1 (en) * | 2014-10-24 | 2022-06-29 | Hitachi Energy Switzerland AG | A hardened inductive device and systems and methods for protecting the inductive device from catastrophic events |
| US11914057B2 (en) | 2015-10-07 | 2024-02-27 | Hitachi Energy Ltd | System for detecting an object approaching and/or impacting electrical equipment |
| WO2018136158A1 (en) | 2017-01-20 | 2018-07-26 | Yaskawa America, Inc. | Method and system for environmental sealing of electrical enclosures |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2496062B (en) | 2014-10-29 |
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