US3383446A - Method of producing electrical bushings - Google Patents

Method of producing electrical bushings Download PDF

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Publication number
US3383446A
US3383446A US486463A US48646365A US3383446A US 3383446 A US3383446 A US 3383446A US 486463 A US486463 A US 486463A US 48646365 A US48646365 A US 48646365A US 3383446 A US3383446 A US 3383446A
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United States
Prior art keywords
mould
resin
cylinder
conductor member
cylinders
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Expired - Lifetime
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US486463A
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English (en)
Inventor
Brennecke Hermann
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BASF Schweiz AG
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Ciba AG
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
    • B29C70/62—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres the filler being oriented during moulding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C39/00—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor
    • B29C39/02—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor for making articles of definite length, i.e. discrete articles
    • B29C39/10—Shaping by casting, i.e. introducing the moulding material into a mould or between confining surfaces without significant moulding pressure; Apparatus therefor for making articles of definite length, i.e. discrete articles incorporating preformed parts or layers, e.g. casting around inserts or for coating articles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/58—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising fillers only, e.g. particles, powder, beads, flakes, spheres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/68—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts by incorporating or moulding on preformed parts, e.g. inserts or layers, e.g. foam blocks
    • B29C70/70—Completely encapsulating inserts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/68—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts by incorporating or moulding on preformed parts, e.g. inserts or layers, e.g. foam blocks
    • B29C70/72—Encapsulating inserts having non-encapsulated projections, e.g. extremities or terminal portions of electrical components
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/26—Lead-in insulators; Lead-through insulators
    • H01B17/28—Capacitor type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H01B3/40—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes epoxy resins

Definitions

  • the present invention relates to a method of producing electrical bushings in which a conductor extends through the bushing.
  • capacitor inserts for the purpose of controlling the electric field around a conductor extending through the bushing.
  • These inserts are metal bodies in the form of sheets, foils, braided materials or coatings.
  • the capacitor layers are provided in cylindrical cast resin bodies by applying a conductive lacquer to the surfaces of tubes of various diameters, whereupon the tubes are assembled together the one within the other and after that the interspaces are filled by casting under vacuum.
  • This process takes a great deal of time and moreover involves a high percentage of rejects during manufacture due to poor adhesion between the surfaces of the tubes and the subsequently introduced and hardened casting resin. It has been found that bushings of this kind are liable to ionisation under the influence of the voltage applied in operation.
  • the construction proceeds from outside inwards. There is first of all cast a tube by centrifugal casting and the internal diameter of this tube corresponds to the external diameter of a cylindrical capacitor insert. This tube is mounted in the casting mould. In the next step of the process the capacitor layer is impregnated with casting resin and then fixed inside the tube. After the resin has hardened there are introduced further inserts and the assembly thus built up from the outside inwards.
  • This process has the disadvantages that the centrifugal casting process is expensive and does not easily allow the desired internal diameter of the cast tube to be obtained precisely.
  • the present invention was developed with the object of mitigating the above disadvantages and in a first aspect the invention provides a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the conductor member extends are embedded in a resin, comprising the steps of aligning an elongate conductor member in a mould for receiving a resin; locating in the mould an electrically conductive hollow cylinder surrounding and spaced apart from the conductor member by means of a generally tubular member disposed between the conductor member and the cylinder; introducing a filler material into the mould to at least a level sufiicient to support the cylinder in its spaced apart relationship with the conductor member; withdrawing the tubular member from the mould; introducing a resin into the mould; and hardening the resin to produce the bushing.
  • the invention is applicable to producing a bushing in which a central conductor member extends through a plurality of radially spaced apart conductive cylinders coaxial with the conductor member.
  • the cylinders may be spaced apart by a plurality of tubes which nest one in another.
  • Each tube has a cylinder slidably mounted thereon, the tube supporting the inner cylinder being slid onto the conductor member.
  • Filler material is introduced into the mould to support the cylinders, thereby enabling the tubes to be withdrawn from the mould.
  • no spacers are required as are needed in the previously known processes mentioned above.
  • Apparatus for producing electrical bushings comprise a mould; means for alighing an elongate conductor in the mould; a set of tubes adapted to nest together one inside another; a portion of reduced external cross-section on each tube for slidably receiving a conductive hollow cylinder for mounting a plurality of such cylinders in radially spaced apart relationship with respect to said elongate conductor; and means for manipulating said tubes in the mould.
  • the drawing illustrates an intermediate stage in the production of an electrical bushing and first of all the steps leading to the position shown will be describel.
  • a central conductor 1 was aligned by means (not shown) in the floor 3 of a casting mould 2.
  • a hollow metal cylinder 4 was then pushed on a first centering tube 5, and the latter was slid on to the conductor 1.
  • the casting mould was then filled with a grainy filler material F up to a level N1, and this was enough to fix in place the cylinder 4 sufiiciently.
  • a second centering tube 6, on to which a second larger diameter
  • the cylinders are provided with flanged ends formed by turning over the rims of the cylinder ends, these flanges aiding in holding the cylinders firmly in the filler material.
  • a further, outermost cylinder 8 has radial bushes 9 which, in the complete product, provide voltage connections.
  • This cylinder is preferably introduced into the casting mould 2 before the introduction of the centering tube 5, and is attached to the wall of the mould and centered by means of screws 10 inserted through the wall of the mould to engage the bushes 9.
  • the mould 2 is entirely filled with filler, whereupon the tubes 5, 6 are withdrawn and further filler F is introduced until the space previously occupied by the tubes has been filled in, whereupon the casting resin is introduced.
  • This variant is used mainly in the case of cylinders whose Walls are impermeable to filler.
  • the tubes 5, 6 are withdrawn at the same time and at the same rate as the level of the filler F rises in the mould, in such a way that the lower ends of the centering tubes are always just above the surface of the filler.
  • This second variant is used mainly in those cases where the cylinders have apertured walls permeable to the filler.
  • the apertures may be perforation-s in a solid wall or be the spaces in a braided or mesh wall.
  • the screws 10 in the bushes 9 of the outermost cylinder 8 are withdrawn only after the casting resin has at least gelled. This is to ensure that no resln can penetrate into the bushes which, as already mentioned, function as electrical connections and in particular as earth connections.
  • the conductor 1 Before the conductor 1 is introduced into the casting mould it is preferably treated as follows. Near the upper end a short length 11, about 5 to 10 cm. is roughened and degreased. The remainder of the conductor surface is then coated with a parting agent 12, for example a silicone oil. Over this parting layer 12 and also on to the roughened surface 11 of the conductor there is then applied an electrically conductive coating 13 which can, for example, be a layer of silver.
  • a parting agent 12 for example a silicone oil.
  • an electrically conductive coating 13 which can, for example, be a layer of silver.
  • a conductor treated in this fashion is bonded to the cast resin body firmly and gastightly at the degreased area 11, whereas over the remainder of the length there is left a freedom for sliding movement between the conductor and the resin body, so that longitudinal extensions of the conductor 1 are not transmitted to the resin body. Differences in expansion between the resin body and the conductor 1 may destructively affect the insulation if the two are bonded along the whole length of the conductor.
  • the conductive silver coating 13 prevents ionisation in the boundary layer 12 because the coating is electrically bonded to the conductor at the area 11 and this has the result that the two surfaces of the layer 12 are always both at the some potential.
  • the tubes 5, 6 and so forth fit slidably within each other at their upper portions 5a, 6a and so forth.
  • the lower portions of the tubes are of reduced diameter to accommodate the cylinders, the reduction in radius of the lower portions being greater than the wall thickness of the cylinders, so that when a set of tubes are nested together annular spaces 14 are formed between adjacent tubes to accommodate the cylinders.
  • the upper portions of each tube can have projection guide members around its outer peripheries to slide along the inner surface of the next outer tube.
  • the supporting and locating efiect large-grained fillers particularly quartz and calcite, whose maximal grain size is between 1.2. and 1.5 mm.
  • hardening casting resin mixtures containing fillers particularly based on epoxide or polyester resins.
  • the resin mixture can, if de sired, contain a further filler whose average grain size is less than one-fifth and preferably approximately of the average grain size of the filler previously used as a supporting agent. In this way the amount of filler can be increased (-up to 70 to by volume) so that in the final product the insulation body has about the same ooefiicient of thermal expansion as have the conductor and the metal inserts.
  • the steps of introducing and hardening the casting resin proceed as required with the application of pressure and vacuum.
  • the casting mould, already filled with filler is closed at the top and, if necessary, evacuated (1 mm. Hg) and filled with an inert gas, for example CO This evacuating and filling process is repeated several times, and then the casting resin mixture is introduced if necessary under pressure (10 atm. g.).
  • the casting mould is provided with the necessary connections in its cover and floor, and by these connections the mould can if desired be connected to a suitable casting apparatus (not shown).
  • the resin is then hardened under the conditions prescribed for the particular mixture.
  • a casting apparatus particularly suitable for the purpose is described and shown in French patent application 1,386,652 (British patent application 5145/64).
  • Example 1 For locating the cylinders in place and for filling up the casting mould there was used a dried mixture of quartz sands in which the grain sizes were between 0.5 and 2.0 mm.
  • the casting resin mixture had the following composition:
  • a polyglycidyl ether resin liquid at room temperature and having an epoxy content of 5.3 epoxide equivalents per kg. prepared by reacting epichlorohydrin with bis-(4-oxyphenyl)-dimethylmethane in the presence of alkali) together with 100 parts by weight of hardening agent in the form of a modified mixture of polycarboxylic acid anhydride, said mixture being liquid at room temperature, there were added with agitation, at a temperature of 80 to 100 C. and under a vacuum of 30 mm.
  • Hg 300 parts by weight of a calcite obtainable under the name Omya BLR-Z (Pluess- Staufer, Oftringen) and having an average particle diameter of 5 microns, and the whole agitated for about another hour.
  • a calcite obtainable under the name Omya BLR-Z (Pluess- Staufer, Oftringen) and having an average particle diameter of 5 microns, and the whole agitated for about another hour.
  • the casting resin mixture was now ready for application.
  • Example 2 For pre-fixing the cylinder and for filling up the casting mould a quartz sand mixture as in Example 1 was used.
  • the casting resin mixture had the following composition:
  • Example 3 For pre-fixing the cylinder in place and filling up to mould a mixture of quartz sands as in Example 1 was used.
  • the casting resin mixture had the following composition:
  • a process for producing an electrical bushing in which a conductor member extends through a plurality of radially spaced apart cylinders coaxial with said conductive member comprising the steps of coaxially aligning in a mould a central elongate conductor member, a plurality of conductive cylinders and a plurality of tubes disposed alternately with the cylinders to space the latter from each other and from the central conductor member; introducing a filler material into the mould to support the cylinders therein whilst withdrawing the tubes from the mould whereby the positions of the cylinders with respect to the central conductor member are maintained; adding a casting resin into the mould; and hardening the resin to produce a bushing.
  • a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the member extends are embedded in a cast resin comprising the steps of aligning an elongate conductor member in a mould for receiving a casting resin mixture; locating in the mould an electrically conductive, apertured, hollow, cylinder surrounding and spaced from the conductor member by means of a tube disposed between the conductor member and the cylinder; introducing a filler material into the mould to at least a level sutficient to support the cylinder in its spaced apart relationship with the conductor member, withdrawing the tube from the mould as the filler material is so introduced; introducing a casting resin into the mould; and hardening the resin to produce a bushing.
  • a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the conductor member extends are embedded in a resin comprising the steps of aligning an elongate conductor member in a mould for receiving a resin; locating in the mould an electrically conductive hollow cylinder surrounding and spaced apart from the conductor member by means of a generally tubular member disposed between the conductor member and the cylinder; introducing a filler material into the mould to at least a level sufficient to support the cylinder in its spaced apart relationship with the conductor member; withdrawing the tubular member from the mould; introducing filler material into the remainder of the mould; introducing a resin into the mould; and hardening the resin to produce the bushing.
  • a process as claimed in claim 3 in which the resin is mixed, prior to introduction into the mould, with a further filler material the grain size of which is about one hundredth the grain size of the first-mentioned filler material.
  • a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the conductor member extends are embedded in a cast resin comprising the steps of coating 2. portion of an elongate conductor member with a parting agent; applying a coating of conductive material over said parting agent and onto said member to form an electrical connection therewith; aligning the conductor member in a mould for receiving a resin; locating in the mould an electrically conductive, hollow cylinder surrounding and spaced apart from the conductor member by means of generally tubular member disposed between the conductor member and the cylinder; introducing a filler material into the mould to at least a level sufiicient to support the cylinder in its spaced apart relationship with the conductor member; withdrawing the tubular member from the mould; introducing filler material into the remainder of the mould; introducing a resin into the mould; and hardening the resin to produce the bushing.
  • a process for producing an electrical bushing in which an elongate conductor member extends through a plurality of radially spaced apart conductive cylinders coaxial with the member comprising the steps of locating an elongate conductor member in a mould; sliding over the conductor member a first tube and a first hollow, conductive cylinder slidably fitted upon the tube and having a portion projecting therefrom the internal aperture through said first tube having a cross-section corresponding to the cross-section of the conductor member to provide a close fit on the latter; introducing a filler material into the mould to a level below said first tube to support the projecting portion of the first cylinder; sliding over said first tube a second tube and a sec ond, hollow, conductive cylinder slidably fitted upon said second tube and having a portion projecting therefrom, the internal aperture through said second tube having a cross-section corresponding to the cross-section of said first tube to provide a close fit on the latter; introducing further filler material into the mould to support the projecting
  • a process for producing an electrical bushing in which a conductor member extends. through a plurality of radially spaced apart, cylinders coaxial with said conductive member comprising the steps of coaxially aligning in a mould, a central elongate conductor member, a plurality of hollow, conductive cylinders and a plurality of tubes disposed alternately with the cylinders to space the latter from each other and from the central conductor member; introducing filler material into the mould to support the cylinders therein; withdrawing the tubes from the mould; adding further filler material to occupy the space vacated by the tubes; introducing a casting resin into the mould; and hardening the resin to produce a bushing.
  • a process of manufacturing an electrical bushing having a conductor extending therethrough comprising the steps of making a plurality of tubes having first portions thereof adapted to fit snugly one within the other for locating the tubes coaxially about an axis at increasing radial distances from the axis, and having second portions thereof of reduced diameter compared to the re spective first portions; making a plurality of hollow cylinders of electrically conductive material and having internal diameters corresponding to the external diameters of said second portions to enable a cylinder to be closely fitted onto each second portion and each cylinder having a wall thickness less than the difierence in outer diameter between the first and second portions of the tube onto which it is adapted to fit; aligning in a mould said tubes and the cylinders fitted thereto with each cylinder projecting beyond its associated tube towards the bottom of the mould; introducing a filler material into the mould to support the cylinders therein; Withdrawing the tubes from the mould leaving the cylinders held in position therein by the filler material; introducing a casting resin
  • a method of locating a plurality of conductive cylinders for an electrical bushing in a mould in a predetermined radially spaced apart relationship with a central conductor member the steps of sliding a plurality of cylinders of different internal diameters onto tubes having first portions of different external diameters and second portions of greater external diameters than the respective first portions and of difierent internal diameters whereby the second portions may be nested one within another and the cylinders may be supported on the first portions in radially spaced apart relationship; aligning the nested tubes with the cylinders fitted thereto in a mould with the ends of the cylinders near the bottom of the mould spaced progressively further away from the bottom of the mould from the inner to the outer cylinder; and introducing a filler into the mould to support the cylinders therein upon withdrawal of the tubes therefrom.
  • a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the conductor member extends are embedded in a resin comprising the steps of aligning an elongate conductor member in a mould; sliding over the conductor member a tube and a hollow conductive cylinder slidably mounted on the exterior of the tube and having a flanged end projecting from the tube for positioning near the bottom of the mould when the tube is fitted on the conductor member; introducing a filler material into the mould to cover the flanged end of the cylinder to support the cylinder; withdrawing the tube from the cylinder; introducing filler material into the remainder of the mould; introducing acasting resin into the mould; and hardening the resin to produce the bush mg.
  • a process for producing an electrical bushing in which a conductor member and a conductive cylinder through which the conductor member extends are embedded in a resin comprising the steps of locating a first electrically conductive, hollow cylinder in a mould by attaching it to the mould; aligning an elongate conductor member so as to extend through said first cylinder, locating in the mould a second electrically conductive, hollow cylinder of lesser diameter than said first cylinder between the latter and the conductor member by means of a tube disposed between the conductor member and said second cylinder; introducing a filler into the mould to at least a level sufiicient to support the cylinder in its spaced apart relationship with the conductor member; withdrawing the tube from the mould; introducing filler material into the remainder of the mould; introducing a resin into the mould; and hardening the resin to produce the bushing.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Mechanical Engineering (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Epoxy Resins (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Organic Insulating Materials (AREA)
  • Insulating Bodies (AREA)
  • Insulators (AREA)
US486463A 1964-09-17 1965-09-10 Method of producing electrical bushings Expired - Lifetime US3383446A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH1210664A CH422932A (de) 1964-09-17 1964-09-17 Verfahren und Einrichtung zur Herstellung von giessharzisolierten elektrischen Hochspannungsdurchführungen mit in der Isolation eingebetteten elektrisch leitenden Einlagen

Publications (1)

Publication Number Publication Date
US3383446A true US3383446A (en) 1968-05-14

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ID=4379906

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US486463A Expired - Lifetime US3383446A (en) 1964-09-17 1965-09-10 Method of producing electrical bushings

Country Status (8)

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US (1) US3383446A (enrdf_load_stackoverflow)
AT (1) AT262410B (enrdf_load_stackoverflow)
BE (1) BE669706A (enrdf_load_stackoverflow)
CH (1) CH422932A (enrdf_load_stackoverflow)
DE (1) DE1275274B (enrdf_load_stackoverflow)
GB (1) GB1113453A (enrdf_load_stackoverflow)
NL (1) NL6512076A (enrdf_load_stackoverflow)
SE (1) SE318638B (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3490731A (en) * 1969-03-26 1970-01-20 Permali Inc Bushing insulator molding device
US4173822A (en) * 1975-07-10 1979-11-13 Interelectric Aktiengesellschaft Method for assembling a stator for an electric machine
US4327479A (en) * 1977-12-30 1982-05-04 Interelectric Aktiengesellschaft Method for assembling a stator for an electric machine
US4407770A (en) * 1981-03-25 1983-10-04 Stronghold International Ag Cable anchorage
US5230850A (en) * 1991-05-16 1993-07-27 Lewis Raymond O Fan blade reinforcement using bonded hollow spheres
US5451352A (en) * 1992-02-03 1995-09-19 Pcc Composites, Inc. Method of forming a diamond composite structure
US6395207B2 (en) * 1999-05-24 2002-05-28 Eastman Kodak Company Micrograin adhesive method and a joint produced by it
CN112373007A (zh) * 2020-10-26 2021-02-19 安徽伊法拉电力科技有限公司 熔断器耐高温绝缘护套及绝缘护套成品供料设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI60625C (fi) * 1978-06-13 1982-02-10 Stroemberg Oy Ab Foerfarande foer framstaellning av en stoedkonstruktion foer lindningen i elektrisk maskin

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1315365A (en) * 1919-09-09 Method of making electromagnets
US1403409A (en) * 1919-05-09 1922-01-10 Nat Carbon Co Inc Dry cell
US3257501A (en) * 1961-04-20 1966-06-21 Westinghouse Electric Corp Self-cleaning electrical insulator constructions

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT204773B (de) * 1952-05-23 1959-08-10 Moser Glaser & Co Ag Verfahren zum blasenfreien Ausfüllen von Räumen im Schleuderguß

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1315365A (en) * 1919-09-09 Method of making electromagnets
US1403409A (en) * 1919-05-09 1922-01-10 Nat Carbon Co Inc Dry cell
US3257501A (en) * 1961-04-20 1966-06-21 Westinghouse Electric Corp Self-cleaning electrical insulator constructions

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3490731A (en) * 1969-03-26 1970-01-20 Permali Inc Bushing insulator molding device
US4173822A (en) * 1975-07-10 1979-11-13 Interelectric Aktiengesellschaft Method for assembling a stator for an electric machine
US4327479A (en) * 1977-12-30 1982-05-04 Interelectric Aktiengesellschaft Method for assembling a stator for an electric machine
US4407770A (en) * 1981-03-25 1983-10-04 Stronghold International Ag Cable anchorage
US5230850A (en) * 1991-05-16 1993-07-27 Lewis Raymond O Fan blade reinforcement using bonded hollow spheres
US5451352A (en) * 1992-02-03 1995-09-19 Pcc Composites, Inc. Method of forming a diamond composite structure
US6395207B2 (en) * 1999-05-24 2002-05-28 Eastman Kodak Company Micrograin adhesive method and a joint produced by it
CN112373007A (zh) * 2020-10-26 2021-02-19 安徽伊法拉电力科技有限公司 熔断器耐高温绝缘护套及绝缘护套成品供料设备
CN112373007B (zh) * 2020-10-26 2023-08-29 国网天津市电力公司宁河供电分公司 熔断器耐高温绝缘护套及绝缘护套成品供料设备

Also Published As

Publication number Publication date
CH422932A (de) 1966-10-31
GB1113453A (en) 1968-05-15
AT262410B (de) 1968-06-10
NL6512076A (enrdf_load_stackoverflow) 1966-03-18
BE669706A (enrdf_load_stackoverflow) 1966-03-16
SE318638B (enrdf_load_stackoverflow) 1969-12-15
DE1275274B (de) 1968-08-14

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