DE2210886A1 - lubricant - Google Patents

Description

PATENT LAWYERS DipUng. WERNER COHAUSZ Dipf.-Ing. WILHELM FLORACK Dipl.-Ing. RUDOLF KNAUF

4 Düsseldorf, Sdiumannstrasse 97 .2.2 I U 8 8 6

Joseph Lucas (industries) Limited

Great Kin ^ Street

GS-Hirraiiifth on March 6, 1972

Skiing racks

The invention relates to lubricants for use in electrical Gate directions.

One known lubricant for use in electrical devices consists of a viscous, lubricating base liquid in the form of a high molecular weight polypropylene glycol mixed with a finely divided bentonite clay filler to form a viscous paste or grease. However, there is a problem with this known lubricant in that its lubricating properties are adversely affected when the lubricant is used in electrical devices using high amperage and low voltage. Devices in which such conditions exist are prone to high temperature arcs and it has now been found that a high temperature arc not only burns off the polypropylene glycol base fluid, but does not leave a harmful residue as well The process of converting the finely divided bentonite filler into coarse particles is reflected, which then conflict with the lubricating properties of the remaining lubricant. It has also been found that the problem associated with this known lubricant can be solved by mixing a finely divided silica filler with the lubricating base substance instead of the bentonite clay filler, since the particle size of the silica is not changed by burning the base liquid.

209839/1087

Wa / Ti - 2 -

Accordingly, the invention resides in a lubricant which is characterized by a viscous lubricating base fluid which is mixed with a filler in the form of finely divided silica.

It is preferably the lubricating base fluid around polypropylene glycol, and conveniently the molecular weight is of pdypropylene glycol more than 2000.

Preferably, the lubricant between '2 ^c / o and 10 o ^ finely divided silica, based on the weight contains.

The particle size of the silica is expediently in the Of the order of 120 Ang3tröia.

Glycerol is preferably added to the mixture of polypropylene glycol and finely divided filler.

The mixture preferably further contains benzotriazole.

In one embodiment of the invention, a lubricant prepared for use in electrical devices by adding 2 parts by weight of benzotriazole to 60 parts by weight of polypropylene glycol are dissolved and then 6 parts by weight of finely divided silica are stirred into the solution until it is viscous Paste is created. The silica used is that under the Uarennahiaen Cab-0-Üil N5, although others are also sold Grades of smoked silica that is sintered into branched chains and an average particle size are suitable on the order of 120 angstroms. The paste made from polypropylene glycol and silica, 1-1 / 2 parts of pure glycerola are added, the glycerol in the paste for about 2 to ρ minutes is stirred in until a thick fat is obtained. The fat is then diluted with a further 0 parts by weight of polypropylene glycol, which is gradually added to the fat, stirring frequently

209839/1087 " ³ "

in order to let a final fat be disfigured, which is a penetration word in the range of 500Θ, it genes according to the I.P. method Γ> θ / 64 · It is understood that in the above description the The term "parts by weight" means parts by weight of the finished fat.

The benzotriazole is added to the fat, because the jet is needed to specialize the moving parts of an electrical L-switch that has Eupfer contacts. The benzotriazole has the sifect of preventing oxidation of contacts. The glycerol is added to the mixture of polypropylene glycol and silica to improve the oleophilic properties of the silica and to produce a stable fat because it does not tend to stand Although in the above example the concentration of glycerol is such that the ratio of glycerol and silica 1: 4 based on the dish is and is also preferred because it has the required low electrical conductivity for use in electrical If there are devices, greater concentrations of glycerol can be added to produce a thin, clear fat. It will be understood that a fat for use in electrical devices must have low electrical conductivity, μλ the likelihood of sparking through the fat or to decrease across the bed when a;,. tro: aflu3 by indu active loads in the device are interrupted, although the electrical conductivity of the i'ett is not so high that any insulation provided for the device is disrupted,

Preferably, the isolypropylene glycol used in the present example has a molecular weight of more than 2000, and in particular in this example it has a molecular weight of 2 × 2 ^T j. lic is understood that the use of ^f i i.Ol7; propjlengl; kol with a hoiieij Iiolekulargcwichi. preferred vi: ■: ■ <?., because it has a low pressure, which means that the climate control ice can be used at higher temperatures. .But beyond that you are bad-

209839/1087

8AD ORfGINAL

2110886

that for the purpose of reducing the permanent pressure of the Lubricant without adversely affecting neutrality or the lubricating properties additives such as polypropylene glyokladipat 'In amounts up to 10 wt .- / and castor oil in Iengen up to 45 wt .-> can be added to the lubricant. Further It is envisaged that the polypropylene glycol used in the preceding example will be replaced in part or in whole by other known ones lubricating base fluids can be replaced.

When using the lubricant prepared above in an electrical device under such operating conditions that a high temperature arc occurs is detected, da.3 it is the polypropylene glycol of the lubricant it burns off, but the particle size of the silica filler remains unchanged after the polypropylene glycol is burned, so that the lubricating properties of the remaining lubricant are not influenced. Furthermore, the lubricant prepared above is less likely to separate when standing, and it shows better lubricating properties than άε, ε known Lubricant made from a mixture of polypropylene glycol and a bentonite clay filler. Uc is also established It has been suggested that best results are obtained when the lubricant contains between 2 and 10% by weight of the silica filler.

Patent claims

209839/1087

Claims (6)

Pat ent -.mis orüche 1. '. Technical agent, £; ekennsstretched by a viscous serving
Green liquid, the one with one. > ällstoif in the 'Joxa. i'a divided hi he; oils ;: de mixed i :: t. 2. Jchmiermittel according to claim 1, characterized, gekennseich.net, that the The base fluid is polypropylene glycol. ; ■. Lubricant according to claim 2, characterized in that the Polypropylene glycol has a molecular weight of more than 2000 hs, t. 4 · Lubricant according to one of claims 1 to 3, characterized in that it is between 2 and 10 wt .- /: the finely divided
Contains silica. 5. iduiiermittcl according to one of claims 1 Ms 4 »characterized in that da.j die! 'a divided silica one particle size into der Gröijenordnun,:; of 120 azi ^ -strömin has. 6. Lichmienaittel according to one of claims 1 to 5 »
due to the glycerol it contains » "/.. ', Chmiermittel according to claim 6, characterized in that ά & ε Gerichtcverhülinis of glycerol is too silica 1j / _r. v. [Cli: .iiornittol r.-ach einera of claims 1 to 7 »characterized eteim ^ z ^ ichnet, da / he:. Senzotriazol contains. j. ochmierjüitüGl ncch one of the cracks 1 to C _} damcoh ^ e ^ Diin hnet, dr. . c- bic au Z ₁ O Cr ;;, ~, Itizinucöl entLilllu, 2098 39/1087 _{3A0 0Rffi} ,