DE2002333A1 - Electrical contact grease - Google Patents

Description

1BERLIN33 S MUNICH 27

Augu.te-Viktorla-Strasse 65 Dr.-Ιπα. HANS RUSCHKE Plenzanwier Strasse 2

Pat. Dr. Ruechke, _lfP -iiP - »* ^ ii * n Pat.-Anwait Aguler

Telephone: 0311 / ™ Dipl.-Ing. H.E I N Z AG U LA R WtanOMU «« »

Telegram address "ee: PATENTANWÄLTE Telsgismm-Adreaae: Quadrature Berlin Quadrature Munich

■ Specimen copy j

■ l'-vi never ⁵ -! being changed, j

η 2750

Matsushita Electric Industrial Company, Ltd., Kadoma, Osaka, Japan

Electric contact fat

Summary:

An improved contact grease is proposed »The grease consists essentially from

a) a major amount of paraffinic mineral oil;

b) 10 to 20% by weight of a mixture of metal tires as a thickener, the Geraisch of the metal soaps essentially from

(i) 40 to 65 wt .- # barium soap} (ii) 25 to 40 wt., ~ # lithium soap and (iii) 10 to 20 wt% alurainium soap consists; and

c) 7 to 15% by weight of at least one chlorinated aromatic Hydrocarbon or a derivative thereof "

109831/1851

The present invention relates to an electrical contact grease, which is particularly suitable for power switches of electrical machines and equipment is suitable.

The usual electrical contacts, e.g. in televisions and radios are subject to failure and welding of the contact and are therefore susceptible to disturbances such as sound disturbances, Image disturbances, failure of the contact opening, etc., responsible.

These disturbances can be avoided to a certain extent by using the previous electrical contact greases · your application however, has not been fully satisfactory due to the complicated nature of the electrical contacts. A failure The contact is generally caused by oxidation, sulfation and wear and tear of the metal surfaces of the contact as well caused by a sludge formed by oxidation, polymerisation and combustion of the fat itself.

For excellent contact greases to eliminate such malfunctions There has long been a need, particularly in the case of contacts made of non-precious metals such as copper or brass, which are easily prone to contact failure.

The task of the contact grease is therefore to prevent of oxidation, sulfation and wear of the contact metals and thus in the stabilization of the electrical contact resistance. Stand in the prevention of noise isnd at the same time in preventing the contact from melting together by restraining the temperature of the electrical contacts from rising.

The aim of the invention is a contact grease that reduces the increase in the electrical contact resistance of an electrical contact suppressed.

Another object of the invention is a contact grease, which the Prevents wear of an electrical contact.

10 9 8 31/18 51

Another object of the invention is a contact grease, which for Suitable for use in electrical contacts made of copper, ilining, phosphor bronze, beryllium copper or nickel silver are made.

These and other objects of the invention will become apparent from the following description.

A contact grease according to the invention consists essentially of a main amount of paraffinic mineral oil, 10 to 20% by weight of a mixture of ketallic soaps as a thickening agent and 7 to 15% by weight of at least one chlorinated aromatic hydrocarbon or a derivative thereof. According to the invention, the mixture of metal beings consists essentially of 40 to 65% by weight of barium soap, 25 to 40% by weight of lithium soap and 10 to 20% by weight of aluminum soap. The novel contact grease according to the invention prevents the failure of an electrical contact and its sticking together by welding and at the same time ensures a satisfactory contact effect for a longer period of time, especially when used on electrical contacts made of corrodible metals such as copper, brass, phosphor bronze, beryllium copper or nickel-silver. Antirust agents and / or antioxidants are preferably added to the fat mass.

A chlorinated aromatic hydrocarbon or a derivative thereof can be used for a contact grease according to the invention with a boiling point of more than 300 ° C can be used. Chlorinated aromatic hydrocarbons or derivatives thereof serve to prevent the temperature rise and the wear and tear of the contact by burning the fat through Prevent arcing and act as a lubricant at the same time. A better result can be achieved by at least one of the following compounds is used: trichlorodiphenyl, Tetrachlorodiphenyl, pentachlorodiphenyl, hexachlorodiphenyl, Polychlorotriphenyl, pentachlorodiphenyl oxide, pentachlorophenyl benzoate ^ exachLor diphe-nyZrtaethane and pentachloro

109831/18 61

diphenyl ketone. The best results are according to the invention with Trichlorodiphenyl, tetrachlorodiphenyl, hexachlorodiphenyl and polychlorotriphenyl achieved.

If the chlorinated aromatic hydrocarbon or derivative thereof is present in an amount less than about 7% by weight, the temperature rise of the contact increases, while an amount greater than about 15 wt a contact grease with good homogeneity made difficult

The paraffinic mineral oil used according to the invention can be both a pure paraffinic mineral oil as well as an impure paraffinic mineral oil containing a small amount, e.g. up to 30 wt .- #, of aromatic and / or naphthenic mineral oil contains, be. The paraffinic mineral oil preferably has a viscosity of 40 to 180 centistok at 37 »8 ° C and one Aniline point above 90 according to ASTM D611-55 & (American Society for Testing Materials).

Barium soaps, lithium soaps and aluminum soaps including those containing an aliphatic fatty acid residue can be used. Their chemical formulas are represented by Ba (RCOO) ₂ , Li (RCOO) and Al (RCOO) ₅ , where R is an alkyl radical. However, these formulas are not intended to limit the invention to the pure substances, but rather also to include contaminated substances which contain the impurities which cannot be avoided. For example, contains the commercially available Al (RCOO), an amount of less than 20 Gev "- £ on Al (OH) (RCOO) ₂ and the invention is for making a contact grease ·· according usable. The radical R in the above chemical formulas should preferably comprise 12 to 20 carbon atoms • The specifically preferred barium, lithium and aluminum soaps include the stearic acid ·

The content of free fatty acids in these metal soaps is preferably low and is preferably below 2 wt .- #.

109831/1861

~ #% The electrical contact resistance and deteriorates in an amount of less than 40 percent, the resistance of the electrical contact - The barium soap increases when using an amount of more than 65 wt: In connection with the weight percentage of the mixture of metal soaps is to point out the following.. versus welding; the lithium soap increases the electrical contact resistance when it is used in an amount less than 25% by weight and deteriorates the welding resistance when it is used in an amount more than 40% by weight; the aluminum soap in an amount of more than 20% by weight gives a contact grease with a low pour point and poor heat resistance, and an aluminum soap in an amount of less than 10% by weight gives a contact grease with poor homogeneity.

When the amount of the mixture of metal soaps in the fat is less is than about 10% by weight, the resulting contact grease is too soft to be dimensionally stable. A lot of the mix on the other hand, of more than 20 wt .- ^ gives one too hard contact grease

A contact grease according to the invention can be improved by adding an antioxidant and / or rust inhibitor. The preferred antioxidants are n-butyl-p-aminophenol, di-sec-butyl-p-phenylenediamine, ^, V-tetramethyldiaminodiphenylmethane, <* -naphthylaniine, n, n -di-salicylidene-1,2-propylenediamine, 2 , 6-di-tert-butylphenol, 2,4-bimethyl-6-tert-butylphenol, 2,6-di-tert-butyl-p-cresol, 4,4'-methylene-bis- (2, 6-di-tert-butylphenol), 2,2-methyl-bis- (4-methyl-6-tert-butylphenol), 4,4'-butylidene-bis (3-methyl-6-tert. -butylphenol). The preferred rust inhibitors are sorbitan monooleate, a salt of dinonylnaphthalene sulfonate and <* - (2-0 arboxy phenoxy) stearic acid. The amount of the antioxidant is preferably from 0.01 to about 3% by weight, that is to say from 0.01 to 3% by weight of the antioxidant and from about 97 to 99.99% by weight of the contact fat. The amount of the rust inhibitor is 0.01 to 4 wt .- ofcwa '= Roctinhitdtorr, at about 96 \>Sz'';,' /) weight j

- 6 of the contact grease.

A mixture of paraffinic mineral oil, a mixture of metal soaps and a chlorinated aromatic hydrocarbon or its derivative with or without antioxidant and roet inhibitor is heated to 200 ^ 250 ° C to form a homogeneous liquid and then cooled to room temperature. The cooled mixture is prepared by one of the usual methods, e.g. on a three roll mill, ground and then subjected to air foam removal under reduced pressure.

The obtained fats are smooth and buttery in consistency and have excellent mechanical and mechanical properties thermal stability.

The following examples are intended to illustrate, but not limit, the invention.

example 1

A mixture of 7 ^, 7 g of paraffinic mineral oil with a viscosity of 60 Centistok at 37.8 ° C and an aniline point of 111.7 ° C, 8 g of barium stearate (melting point 235 ° C), 5 g of lithium stearate (Melting point 221 ° C.), 2 g aluminum stearate (melting point 112 ° C.), 10 g polychlorotriphenyl, 0.1 g 4-, 4'-tetramethyldiaminodiphenylmethane and 0.2 g of sorbitan monooleate is stirred and heated to 230 to 240 ° C.

After homogenization, the equipment is poured into a bowl, cooled to room temperature and milled on a three-roller mill; then the foam left in the fat is underneath removed under reduced pressure. The fat obtained is stable and has an ASTM penetration of 332 and a pour point of 120 ° C. The grease is applied to a contact made of copper and brass. The behavior of the fat will shown as Example 1 in Table I.

109831/1851

Example 2

A mixture of 70.5 g paraffinic mineral oil with a viscosity of about 50 centistok at 37.8 ° C and one aniline point of 102.7 ° C, 10 g of barium stearate (melting point 235 ° C), 7 g Lithium stearate, 4 g aluminum stearate, 8 g polychlorotriphenyl and 0.5 g 2,6-di-tert-butylphenol are heated to 235 to 245 ° C After the homogenization, the mixture is cooled, milled and treated in a similar way as in Example 1 Experimental results obtained in a similar manner to Example 1 are given in Table I.

Example 3

A mixture of 73 »8 g paraffinic Hineral oil with a viscosity of 120 Centistok at 37.8 ° C and an aniline point of 114.9 ° C, 6 g of barium stearate (melting point 250 ° C), 4 g Lithium stearate (melting point 221 ° C.), 2 g of aluminum stearate, 14 g of polychlorotriphenyl and 0.2 g of the sodium salt of dinonylnaphthalene sulfonate is stirred and heated to about 250 ° C. The clear, liquid solution is treated as in Example 1. The test results obtained in a manner similar to Example 1 are shown in Table I.

Example 4

A mixture of 75 g of paraffinic mineral oil with a viscosity of 80 centistok at 37 »8 ° C and an aniline point of 114.0 ° C, 7 g barium stearate, 5 g lithium laurate (melting point 219 ° C), 1.5 g aluminum stearate, 8 g hexachlorodiphenyl, 0.1 g Tetrabase and 3 g of sorbitan monooleate are heated in a beaker until its temperature reaches about 240 ° C. The received The mixture is treated further as in Example 1. The test results obtained as in Example 1 are given in Table I.

109831/1851

Example 5

A mixture of 72.9 g of paraffinic mineral oil with a viscosity of 60 Centistok at 37ι8 ° C and an aniline point of 111.7 ° C, 10 g barium stearate, 5 S lithium laurate (melting point 219 ° C), 3 g of aluminum stearate and 9.1 g of tetrachlorodiphenyl stirred and heated in a beaker until its temperature has reached about 250 ° C. The resulting mixture is treated in a similar manner to Example 1. The results of Experiments carried out as in Example 1 are given in Table I.

Example 6

A mixture of 70.9 g of paraffinic mineral oil with a viscosity of 80 centistok at 37.8 ° C and an aniline point of 114.0 ° C, 9 g barium stearate (melting point 240 ° C), 6 g lithium laurate (melting point 219 ° C), 2 g aluminum stearate (melting point - point 110 ° C), 12 g of polychlorotriphenyl and 0.1 g of tetrabase stirred, heated in a beaker and then treated in a similar manner as in Example 1 Test results are given in Table I.

Example 7

A mixture of 69.8 g of paraffinic mineral oil with a viscosity of 78.2 centistok at 37.8 ° C and an aniline point of 104.2 ° C, 10 g of barium stearate, 6 g of lithium stearate, 2 g Aluminum stearate, 11 g of polychlorotriphenyl, 0.2 g of tetrabase and 1 g of "Span 80" are stirred, heated in a beaker and then further treated as in Example 1 The test results obtained as in Example 1 are shown in Table I.

Example 8

A mixture of 73.7 G paraffinic mineral oil having a viscosity of from 80 · Vie Centistok at 37.8 ° C and an aniline point of 114.0 ° C, 8 g Bariumst £ Q, did feg i.UH "tumstearat, 2.2 g aluminum

109831/1851

stearate, 10 g polychlorotriphenyl and 0.1 tetrabase is stirred, heated in a beaker and in a similar manner as in Example 1 treated. The test results obtained as in Example 1 are given in Table I.

Example 9

A mixture of 76.5 g paraffinic mineral oil of low viscosity from 12C Cenbistok at 37 »8 ° C and an aniline point of 114.9 ° C, 8 g barium stearate, 4 g lithium stearate, 1.5 g aluminum stearate, 9 g hexachlorodiphenyl and 1.0 g 2,2'-methylenebis (4methyl-6-tert.-butylphenol) is stirred, heated in a beaker and treated in a manner similar to Example 1. the Experimental results obtained in a manner similar to Example 1 are shown in Table I.

Example 10

A mixture of 73 »8 g of paraffinic mineral oil with a viscosity of 60 Gentistok at 37 »8 ° C and an aniline point of 117 »2 ° C, 7 g barium stearate, 6 g lithium stearate, 2 g aluminum tearate, 11 g Iolychlortriphenyl and 0.2 g tetrabase is stirred, heated in a beaker and in a similar V / eise as treated in example 1. The test results obtained as in Example 1 are given in Table I.

The tetrabase mentioned in the preceding examples is 4,4'-tetramethyldiaminodiphenylmethane.

109331/1851

Table I.

^ - example
\ No. 1 2 copper
Brass 4th 5
■ 6th Combination of
Contact metals copper
Brass
I. copper
Brass 200 copper
phosphorus
bronze copper
Nickel-
silver copper
Brass _, Contact pressure (g) 200 200 30th 200 200 300 co opening speed
co digkeit (cm-sec " ¹ 30th 30th 100 30th 30th 20th X
^. Opening force (g) 100 100 . Change
current
100 100 100 100 ⁰⁰ contact chip
^ tion (V) Change
current
100 Change
current
100 Lamps
load
normal: 4 Change
current
100 Change
current
100 Change
current
100 Contact current (A) sharpen
load:
30th
normal: 4 Sharpen.-
load:
50
normal: 4 Lamps
load
normal: 4 sharpen
load:
30th
normal: 4 sharpen
load:
30th
normal: 4

Table I (port setting)

^ "* - ~~ - * ^^^ example number of
Operations 1 • 2 • 3 . 4th • 5 . 6th ■ α 0 rs tar 10,000 8th 7th 5 4th 5 3 601
: wide
Sl) 30000 18th 24 34 25th 29 10 co aJvfÜ- 50000 39 55 49 32 85 42 ^ - O cn
_ »Number of
and switch off
gen up to the point of
welding 28 79 81 44 162 78 ^ 50000 y 50000 yr 50000 y> 50000 35000 y 50000

KJ CO U)

Table I (continued)

""" Example
- ··. No. I 7
ί
S. 8th 9
I. i ίο trade
usual
!Contact- ] commercial;
\ usual,
': Contact j
j ^fet B- { Combination of
Contact metals copper
Beryllium-
copper copper
Beryllium-
copper copper
Brass copper
Beryllium-
copper ¹
'Copper
I.
: Brass
I. ! Copper J
'Brass i
ι ι Contact pressure (g) 300 300 200 200 j 200 ' 200 Opening
speed
ι λ γη φ c Q λ ι 20th 20th 30th 30th !
30th 30th Opening force (g) 100 100 100 100 100 100 Contact chip
voltage (V) Change
current
100 Change
current
100 Change
current
100 Change
current
100 Change
current
100 Change
current
100 Contact current (A) Lamp holder
burden
normal: 4 Lamp holder
burden
normal: 4 sharpen
bela
stung: 30
normal: 4 sharpen
bela
stung: 30
normal: 4 sharpen
bela
stung: 30
normal: 4 sharpen
bela
stung: 30
normal: 4

ro co co co

Table I (port setting)

\." Example 886OL
resistance number of
Operations 7th 8th Ul ! j
y 50000 \ > 50000
i 9 8th 10 trade
usual
Contact grease
A. trade
usual
Contact grease
B. ; 325 S8L / L
Contact
(m J 0 29 22nd 1580 10,000 4th 30000 j 15 j 48 39 9 8 7 1420 18th 50000 j 22 I 75 69 15th 255 , 7200 Number of Be
services up
for welding -jr 50000 48 1250 83 : 2310 y. 50000 ; 3800
!

ι ro co co

Claims (5)

Claims 1 · contact grease, characterized in that it is essentially the end a) a major amount of paraffinic mineral oil; b) 10 to 20 wt .- ^ of a mixture of motorized soaps as a thickening agent, the mixture of metal soaps essentially consisting of (i) 4-0 to 65 wt% barium soap; (ii) 25 to 40 weight percent lithium soap; and (iii) 10 to 20 wt. # aluminum soap exists, and c) 7 to 15% by weight of at least one chlorinated aromatic hydrocarbon or a derivative of which consists. 2. Contact grease according to claim 1, characterized in that the barium soap, lithium soap or aluminum soap essentially correspond to the formulas Ba (RCOO) ₂ , Li (RCOO) and Al (RCOO) ₅ , in which H is an alkyl radical having 12 to 20 carbon atoms means. 3. Contact grease according to claim 1, characterized in that the chlorinated aromatic hydrocarbon or the derivative one of these can be selected from the following compounds: trichlorodiphenyl, tetrachlorodiphenyl, pentachlorodiphenyl, Hexachlorodiphenyl, polychlorotriphenyl, pentachlorodiphenyl oxide, Pentachlorophenyl benzoate, hexachlorodiphenyl methane and pentachlorodiphenyl ketone. 4. Contact grease according to claim 1, characterized in that it further comprises 0.01 to 3.0 wt .- # of an antioxidant contains n-butyl-p-aminophenol, di-sec.-butyl-p-phenylwidiamine, ^, V-tetramethyldiaminodiphenylmethane, Λ-naphthylamine, n, n'-disalicylidene-1,2-propylenediamine, 2,6-di-tert.-butyl- 109831/1851 phenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butyl-p-cresol, 4.4 ^l -i-iethylene-bis- (2,6-di-tert, -butylphenol), 2,2'-methylene-bis-C ^ -methyl-G-tert.-butylphenol), 4,4'-butylidene-bis- (2-methyl-6-tert «-butylphenol) is known 5. Contact fat according to claim 1, characterized in that it further contains 0.01 to 4.0 wt .- ^ contains an anti-rust agent sorbitan monooleate, a salt of the Dinonylnaphthalinsulfonates or <* -. (2-Oarboxyphenoxy) stearic acid be canoe · Me / He 109831/1851