US2244109A

US2244109A - Sleeve and method for making same

Info

Publication number: US2244109A
Application number: US312386A
Authority: US
Inventors: Charles H Klein
Original assignee: National Telephone Supply Co
Current assignee: National Telephone Supply Co
Priority date: 1940-01-04
Filing date: 1940-01-04
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

' June 3 1941. c. H. KLEIN SLEEVE-AND METHOD FOR MAKING SAME Filed Jan. 4, 194g) INVENTOR. bar/e; h. WEI/7 BY/OZ ATTORNEY. I

Patented June 3.1941 Q UNITED STATESQPATENT OFFICE SLEEVE AND METHOD FOR MAKING SAME Charles H. Klein, Cleveland, Ohio, aasignor to The National Telephone Supply Company Application January 4 11940, Serial No. 31.2 i

'lClaims.

My invention relates to a device for joining metal wires together and more particularly to a metal sleeve which is adapted to firmly grip the ends oi the wires to be joined and which has a high electrical conductivity between-the wires to be Joined and the metal sleeve.

An object of my invention is to provide an internal coating for a-sleeve which coating has an electrical conductivity equivalent substantially equal to that of the wire to be fastened in the sleeve.

An object of my invention is to provide a device for joining the ends of twowires together in a union which is sumciently strong to withstand a pull on one wire with respect to the other and which has a high electrical conductivity.

Another object of my invention is to provide a metal sleeve for anchoring the end of an electrical conductor and to increase the electrical conductivity between the sleeve and the wire without materially decreasing the strength of the connection between the sleeve andthe wire.

Still another object of my invention is to provide a wire attachingsleeve which has a coating on the inner surface thereof.

Still anotherobject of myinvention is to coat the inner surface of an attaching sleeve with a plurality of substances, one of which increases preparatory for coating the inside surifaces oi with one connecting sleeve being more predominately shownthan the others, together with a spray gun for coating the sleeves.

Figure 3 is a cross sectio'nai view connecting sleeves as coated. v

Figure 4 is a longitudinal cross-sectional view of Figure 3 and -shpws a wire positioned to be inserted through an open end thereof.

of one of my Figure 5 is a longitudinal cross-sectional view showing the wire inside the sleeve and after compression has been applied to the outside of the sleeve.

Figure 6 is a cross-sectional view similar. to Figure 3 but shows another variation in the internai coating of my device.

Figure 7 is a view similar to Figure 6 showing still another variation in th internal coating of my device; and

Figure 8 is a view similar to Figure 7 showing two spray guns coating the sleeves.

the holding power of the-sleeve and another of l which increases the electrical conductivity of the sleeve.

A further object of my invention is to furnish an attaching sleeve for connection to a conductor and to provide a method whereby the electrical conductivity of the joint between the sleeve and the conductor can be controlled during manufacture to assure that the conductivity of the joint is equal to or greater than the conductivity'of the wire.

' Another object of my invention is to provide an electrical connection for a wire which has the greatest strength commensurate with the cohductivity desired in the connection.

Still another object of my invention is to provide an electrical connection fora wire which has the largest electrical conductivity commensurate with the strength desired in the connec: tion.

Other objects and a iulier understanding of my invention may be had by referring to the following description and claims, takenin conjunction fwith the accompanying drawing; in

which:

Figure 1- is an end view of a pluralityof my connecting sleeves arranged in a holdingdevice With reference to the drawing, my. invention comprises coating the inner surface of a hollow metal sleeve M with several kinds of materials to increase the conductivity between the sleeve ill and a wire it without materially reducing the holding power between the sleeve Ill and the wire l6.

One manner of coating the inner surface is illustrated in Figures 1 and 2 or the drawing and consists of grouping together a plurality of the sleeves to be coated and spraying them with a material It which is to cover the inside surface For convenience I employ a container it at a slight angle with respect to the sleeves the operator assures that the material 15 strikes the inside wall surfaces.

After grouping the plurality of sleeves Iii in the container I2. the operator tilts the. container at.

a slight angle for his convenience, as shown in Figure 2 and then he takes his spray gun and directs the spray of material at a slight angle to there- V Figure 2 is a side view of the sleeves in Figure 1' or Nichrome."

the longitudinal axisv of the inside surfaces of the sleeve so that thesprayed material impingeathe sleeves for substantially one-half of their longitudinal length. The operator sprays all the sleeves within the container at this slight angle by sweeping the spray material over the entire end surfaces of the plurality of sleeves within the container. By directing the spray at a slight angle with respect to the longitudinal axis of the openings in the sleeves ill the operator insures that the spray material impinges the inside surfaces of the sleeve to make a good coating which adheres firmly to the inside surfaces of. the sleeves. Inasmuch as the spray is directed at a slight angle .to the longitudinal axis of the sleeve,

only a longitudinal arcuate portion of the inside surfaces of the sleeves is coated for each positional setting of the container l2 which holds the plurality of sleeves. .To coat the entire inside surfaces iii of the sleeves with the spray material, the operator rotates the container substantially 90 degrees for each spraying operation. In this manner the operator sprays a substantially 90 degree .arcuate surface for substantially onehalf of the length of the inside surfaces of the sleeves upon each positional setting of the container l2 which holds the plurality of -sleeves. After spraying the upper end of the sleeves III, the operator turns the container i2 end-for-end and repeats the spraying process. Turning the container and the wire it are soft copper any harder metal such as hard copper, bronze, stainless steel, or Nichrome could be used. If the sleeve layer the wire is is made of hard copper the coating material i! could be of bronze, stainless steel If the sleeve it or wire it is made of bronze then onlyvthose metals which are harder than bronze, i. e., stainless steel, and Nichromc, could be used. a The other material which is sprayed on the inside surface ll of the sleeve in is preferably a metal having a high electrical conductivity. This high conductivity rlraetal is designatedby the reference character In sleeves having the entire inside surface coated with the hard material il I have found a that the conductivity from'the wire it to e sleeve iii is low as the metals which are t for their gripping qualities are poor in conductivity.

To produce a sleeve which is good in gripping and high in conductivity, therefore, I coat the inner surface ii with two kinds of metals, one

I! end-for-end and repeating the spraying process'is necessary for long sleeves as One material is harderthan by the balance betweenthe gripping action and the conductivity between the wire and the sleeve. Thus, in the spraying operation, the operator may spray a hard metal, for example, for two 90- 'degree positions of the container i2 and then conductivity between the sleeves and wire. The

metal coatings 17 and i8 sprayed insideof the sleeve are not smooth like electro-plating but consist of hills and valleys which key themselvesinto the wire and sleeve when the sleeve I0 is squeezed into engagement with the wire it.

In connecting the sleeve and the wire, the wire is inserted in the sleeve until it abuts the central stop i3, and then the sleeve is compressed by any of the well known methods of rolling,

drawing, or Squeezing. For a squeezing operation, a constant movement clamping tool may be used to compress the sleeve l0 and the coatings therein upon the wire l6 and force the coatings into intimate engagement with the wire.

The pressure may be applied over spaced areas- 20, ll and 22 thereby causing substantially theentire inside surface In to engage the wire I.-

The hard coating 'i'l which lies on the surface of the sleeve i0 as is shown in Figure 4 is forced to dig into both the sleeve Ill and the wire I! by the squeezing of the clamping tool as may be seen in Figured A-pull' on the wire IS with respect to the sleeve to will not cause the wire to pull out as the hard coating firmly grips boththe sleeve and the wire.

Electrical current flowing through the wire it will pass to the sleeve 10 with a minimum of for strength or gripping qualities and one for,

conductivity.

To formmy improved sleeve, a portion of the inside surface of the sleeve is sprayed th. s

hard metal such as Nichrome'f and the remaining portion is sprayed with a metal ha a higher conductivity. The proportionate share of the inside surface of the sleeve which is sprayed with the hard material and with. the material having a high conductivity is governed conduction loss as the high conductivity coating is lies between the wire and the sleeve and is in close contact with each of them.

In the installation of current carrying wires where low loss by resistance is of importance my device has great utility. A wire which is to be connected to the sleeve has a known resistance and must withstand a known pull. With these values known the area inside the sleeve which must be covered by each of the coatings in order to meet the service conditions can readily be determined. l have illustrated in Figures 3, 6 and 2 several variations in the amounts of the hard coating ill and conducting coating iii. Figure 3 shows half or the inside area covered with each of the difierent coatings. Figure a shows three-quarters of the inside area covered with a metal of high conductivity and one-quarter covered with the metal H which increases the gripping power between the wire it? and the sleeve iii. This type may be used where high conductivity is essential and the stress between the sleeve and the wire is low. Figure 7 shows a sleeve having three-quarters of its inner sun. face i 6 covered with the hard metal iii and onlyv one-quarter covered with high conductivity metal is. This type of sleeve is to he used in connections where great strength is required to resist stress on the wire with respect to the are'used simultaneously, one to spray the sleeve with the hard coating l1 and the other to spray the sleeve with the conducting coating it. Each of the operators directs his spray to strike the container I? at difierent angles and attempts to avoid spraying the same sleeves at the same. time as they each sweep the spray over all the sleeves. As illustrated in Figure 8 the two spray guns it are held laterally apart and are directed at the sleeves in the container from different sides thereby assuring that the metals l1 and it do not impinge on the same arcuate portion of the inside surface of the sleeves. I

Although I have described my invention as spraying molten metal in a manner to cause it to stick to the inside of a hollow sleeve it is to be understood that any means of coating the sleeve 1 is within the purview of my application and that a sleeve on. which a plurality oi metals has been painted or otherwise affixed is deemed a coated sleeve and within the scope or this disclosure.

with a molten metal which has a higher coefll-' cient of electrical conductivity than the said nickel chromium metal, inserting an end portionof the metal wire into an 'end portion of the sleeve and compressing the sleeve and the coatings therein upon the wire. 1

2. The method of making a wire and sleeve joint of high strength and of high electrical conductivity which comprises spraying a portion of the inner wall of'the sleeve with a molten metal comprised of nickel and chromium, spraying another portion of theinner walloi the sleeve with molten bronze, inserting an end portion 0! the 7 metal wire into an end portion of thesleeve and compressing the sleeve and the sprayed metal therein upon the wire.

3. The method of making a wire and sleeve joint of high strength and of high electrical conductivity which comprises simultaneously spraying the inner wall of the sleeve with. a molten metal comprised of nickel and chromium and,

with molten bronze, inserting an end portion of the metal wire into an end portion of the sleeve and compressing the sleeve and the sprayed metal therein upon the wire.

4. The method of making a wire and sleeve the metal of the sleeve or the metal ofthe wire to be joined, inserting an end portion of the wire into an end portion of the sleeve and compressing the sleeve and the sprayed material therein upon the wire to establish an electrical connection which has a conductivity substantially equal to the conductivity of the wire which is joined.

5. A metal sleeve for joining an electrical conductor wire thereto comprising 'a hollow tubular sleeve having an inner surface, an area of said inner surface being coated with a gripping material which is harder than the metal of the said sleeve-and harder than the metal of the wires to be joined and an area of saidinner surface being coated with a material'which is softer than said gripping material and which has a high,

coemcient of electrical conductivity, said second area having a conductivity substantially equal to' the conductivity of the wire to be joined thereto.

6. A metal sleeve for Joining an electrical conductor wire thereto comprising ahollow tubular sleeve having an inner surface, an area of said inner surface being coated with a gripping ma-j terial which is harder than the metal of the said sleeve and harder than the metal oi the wires to be Joined and an area of said inner surface being coated with a material which issofter than saidgripping material and which has a high coefllcient oi el ctrical conductivity, said leeve having a resultant inner surface of the conductivity substantially equal to or better than the conductivity of the whom he joined thereto.

'l. A metal sleeve for joining an electrical conductor wire thereto comprising a hollow tubular sleeve having an inner surface, an area of said inner surface being coated with a gripping ma-- terial comprising nickel and chromium which is harder than the metal of the said sleeve and CHARLES E. KLEIN.