US1935597A - High tension switch - Google Patents

Description

Nov. 14, 1933. c. G. KOPPITZ HIGH TENSION SWITCH Filed Nov. 12, 1928 5 Sheets-Sheet 1 NOV. 14, 1933. c G KQPPITZ 1,935,597

HIGH TENSION SWITCH Filed Nov. 12. 1928 5 Sheets-Sheet 2 NOV. 14, 1933. Q KOPPlTz 1,935,597

HIGH TENSION SWITCH Filed Nov. 12, 1928 5 Sheets-Sheet 3 1933- c. G. KOPPITZ HIGH TENSION SWITCH Filed Nov. 12, 1928 5 Sheets-Sheet 4 I l l I I I l I 1' .I 1- I I l I I l I I I I I I -I I I l I I I l l I l I I l I l I I I I I I I I I I I I I l l I I .I I I I I I I I 1 I I I I 4 I I I l l I l l I I I l I I I l I I I I I I I I l I I I I I I I I I I I I I I I I I l I I if abfozwm m NOV. 14, 1933. c KQPPITZ 1,935,597

HIGH TENSION SWITCH Filed Nov. 12, 1928 5 Sheets-Sheet 5 c'n-z 40 Patented Nov. 14, 1933 HIGH TENSION SWITCH Carl G. Koppitz, Greensburg, Pa., assignor to Railway and. Industrial Engineering Company, Greensburg, Pa., a corporation of Pennsylvania Application November 12, 1928 Serial No. 318,962

14 Claims. (Cl. 200-48) This invention relates to that class of electrical switches used for high potential, outdoor service, though obviously it is not limited to outdoor use. One object of theinvention is the provision of a switch having relatively movable members through which current flows, and in which the contact surfaces of said members are so shaped and so held in contact as to facilitate the flow of current between the members. An object is to provide a switch of the type in which two relatively movable elements have transversely alined portions that are engaged or adapted to be en gaged, and'in which the transversely alined portions have contact surfaces of different curvature such as, for example, a plane surface and a surface of revolution. U v v More specifically, an object is to provide a new type of hinged joint between the links of the movable switch parts, or any hinged parts carrying current, whereby the use of jumpers around the joint is avoided.

A further object is to provide a novel form of switch contact which is particularly well adapted for high tension disconnect switches, which is sembled and is strong and durable in use.

A further object is to provide a novel form of point contact for a disconnect switch.

These and further objects will be apparent from the following description when taken in connection with the accompanying drawings, wherein Fig. l is a plan and g I Fig. 2 a side elevation of one form of rocker switch embodying the invention,

Fig. 3 is an enlarged view of part of the linkage of Figs. 1 and 2,

Fig. 4 is a side elevation and Fig. 5 is an end view of a modified form,

,Fig. 6 shows another form of rocker switch,

Fig. 'I is a partial section and Fig. 8 is a side elevation showing more in detail one form of novel contact,

Fig. 9 is a side view and Fig. 10 is an end view of another modified form.

Referring to Figs. 1 and 2, numeral 1 designates a base upon which are two'stationary insulators 2 and 3 and a rocking insulator 4 for each circuit to be controlled. In these figures there are shown three sets of such'insulators constituting three switches for simultaneously making or breaking circuit in a three-phase system.

The pivoted or rocker insulator 4 is spaced about midway between the stationary insulators 2 and 3 and the conducting cap 5 thereon is pivotally connected to the T-shaped link 6 of the switch made of but two parts, is easily and quickly asblade, the link 6 being pivotally connected in turn to the linkage 7 which has its opposite end 8 hinged to the stationary insulator 2. Link 6 is formed at one end into a contact portion 9 which cooperates with the stationary contact 10 on insulator 3, there being a stop 10' against which link 6 rests when the switch is fully closed.

The pivotal connection between links 6 and 7 and between link 7 and insulator 2 will be described more .in detail, reference being had to Fig. 3. Link 6 is made of relatively hard bronze and terminates at itsv pivotal connection in a head 11 which is approximately hemispherical on its two faces.

Linkage 7 consists of two similar elongated plates of rectangular cross-section, i.'e. straps or links, of copper whose ends abut against the curved faces of head 11 and are pressed into firm contact therewith by means of nut and bolt connection l2 and a heavy coil spring 13. The cap on insulator 2 is also of hard bronze and terminates in a head 14 which has curved or approximately hemispherical surfaces for contacting engagement with the opposed and substantially parallel contact surfaces of the relatively soft copper links 7. Head 14 and links 7 areperforated to receive a bolt 15, and links 7 are firmly pressed against head 14 by heavy spring 16. Since the opposed surfaces of the transversely alined portions of members 6 and 7 are of different curva-r ture, these opposed surfaces do not engage with surface contact but with approximately line con-, tacts. By this construction, there is a relatively hard metal in firm engagement with a relatively soft metal at all points of rubbing contact. The actual area of engagement is very small but the pressure is high, causing a high concentration of current. These surfaces are always kept clean by rubbing and scoring of the metal is avoided, and the necessity of troublesome and expensive jumpers around these points is avoided.

The engaging faces of the stationary and movable contacts are similar in principle to that outlined above, that is, the engaging surfaces comprise one hard metal and one relatively soft metal, with small area of contact and high pressure. The movable contact 9, which is made of bronze in this case, is adapted to be forced between the two parts of the copper contact 10. This contact 10 may be angularly disposed with respect to the insulator, as in Figs. 2 and 8, or it may form in effect a continuation of the insulator as in Fig. 9. In either case, the structural details are similar and such a contact as shown in Fig. 9

-. one another.

will be described more in detail, reference being had to Figs. 4 and 5.

The contact consists of but two separate parts. The base 10 is hollow and open at its bottom. Integral with the base and rising therefrom are the stop 10 and two fingers 10 Each finger 10 has a longitudinal slot therein, extending from the base 10 upward and terminating just short of an enlarged head 10*. The base 10 is perforated in line with the slots in fingers 10 and the enlarged heads 10 have an opening 10 extending from their lower surfaces.

The contact is assembled as follows: The base is inverted from the position shown in Fig. '7, and a strong, steel spring member 10 of U shape is inserted through the openings in base 10 through the slots in members 10 and into the openings 10 in enlarged heads 10 The openings 10 are larger than spring member 10 The spring 10 is held in an assembly jig such that the legs thereof are properly centered in openings 10 and then solder or Babbitt metal is poured into these openings and allowed to harden. The two parts are thus easily and simply united. The base 10 may also be filled with solder or other material, although this is usually unnecessary. It will be understood that base 10 has the usual means for clamping or bolting to an insulator cap.

From this construction, it will be apparent that the relatively hard bronze contact 9, which has rounded engaging faces, is forced between the legs of contact 10, which is of copper. This gives a high concentration of current through a small area of contact, the hard and soft metal being self-cleaning.

Referring again to Figs. 1 and 2, the rocker insulator pins 1'7 are bolted through their flanges 18 to flanges 19 of support 20. A separate sup port 20 is provided for each rocker insulator 4, and each support is shaped to partially enclose and clamp an operating bar 21 which extends transversely of the three switches, whereby they are operated simultaneously. Each support 20 has a lug 22 which is pivoted to base 1 at 23 by means of mountings 24 on said base. A crank arm, not shown, is connected to operating bar 21 either between the switches or beyond the same. By this arrangement, the pivots 23 for the in sulators are relieved of the duty of carrying the operating arm. These operating arms are subjected to heavy torsional strains and the old practice of using the pivot of the rocker insulator as the support for the operating arm required heavy and cumbersome constructions as the bearings were expensive, and were difiicult and expensive to install on the job. By the construction outlined above; the assembly is easily and simply made on the job and bearing 23 may be a simple pivot pin, since it does not sustain any torsional strains.

In Figs. 6 and '7, wherein is illustrated a modification, numeral 25 designates I beams, upon which are mounted six channels 26 in pairs, the open sides of the channels of each pair facing Upon each pair of channels is mounted a complete switch unit, three such units being shown for a three-phase circuit breaker. Pivot lugs 27 carrying pivot pins 28 support two rocker insulators for each switch, each switch having two stationary insulators, as seen in Fig. 6. Pivots 28 support lugs 29 mounted on the open under side of channels 30, upon the upper side of which are clamped the rocker insulators 31. Bars 32 extend from lugs 29 below the pivots 28 and carry counter-weights 33.

Bolted upon the operating channels are cranks 34 whereby the rocker insulators may move about pivots 28 by means of operating rods 35 and driving mechanism designated generally by numeral 36.

Stationary insulators 37 are mounted on channels 26 and have pivoted to their caps 38 the links 39, which in turn are pivotally connected to links 40, and links 40 are pivoted on the caps 41 of rocking insulators 31. The caps 41 early coopcrating contacts for engagement, the contacts comprising an elongated rod 42 with an upturned end 43 and a cooperating rod 44 with a point contact 45. Point 45 comes into direct abutting engagement with the end 43, resulting in a concentrated current density at the contacts.

It will be understood that links 39 and 40 may be formed of relatively hard and soft metals, and built similar to those shown in Figs. 1, 2 and 3. It will also be clear that the invention is not limited to bronze and copper links, since other metals may be used, one of which is relatively harder than the other.

Fig. 8 illustrates another modification of a switch somewhat similar to Figs. 1 and 2, except in the mounting of the operating shaft. Stationary insulator 3 carries contact 10 with stop 10 for engagement by contact 9 on link 6. The movable insulator 4 has a pin 46 pivoted at 23 to lug 24 on base 1. The pin 46 has an offset 47 and the operating shaft 21 is clamped against the pin at this point by U clamps 48, to thereby position the operating shaft 21 at a point spaced from pivot 23.

In Figs. 9 and 10, there is illustrated a vertical switch in which the channel or operating bar is so mounted that it counterbalances a part of the weig t of the blades and/or associated movable elements of the several switches. Specific claims to a counterbalanced switch of this type are presented in my copending application, Ser. No. 444,580, filed April 15, 1930. Mounted on the cross supporting channels 49 are vertical channels 50, there being two such vertical channels for each switch. The two channels 50 of each switch have their webs facing one another and carry two rigid insulator posts 51 and 52, insulator 51 having mounted thereon a switch contact 53 similar to that shown in Figs. 2 and 8, but with the contacting part in alignment with the insulator. Insulator 52 has rod 54 pivoted thereon for engagement with contact 53, the pivot being similar to that shown in Fig. 3.

Rigidly mounted on said rod 54 is a strap 55 to which is pivotally connected the insulator column 56. Operating rod 57 is connected to the other end of insulator column 56 and passes between channels 50 and is pivoted to a crank arm 58 which in turn is bolted to a channel 59, pivoted at 60 to a lug 61 on vertical channels 50.

Bolted to channel 59, preferably between switches, is an operating lug 62, pivotally connected to operating rod 63 which is operated by handle 64. The movement of the parts is indicated by the arrows. It will be seen that bearing 60 may be simply a pin, since torsional strains at this point areobviated. These switches may be provided in units of three for three-phase control.

It will be understood that other embodiments of switches may be designed without departing from the scope of this invention as set forth in the accompanying claims.

I claim:

1. A high potential switch of the type including a stationary insulator pillar terminating in a metal cap, a pivoted insulator pillar terminating in a metal cap, a pair of links, a pivot pin conneoting the adjacent ends of said links, and pivot pins connecting the respective links to said metal caps atpoints remote from the pivotal connection between said links, characterized by the fact that spring means are provided at each of said pivotal connections to force the links into contact with each other and into contact with the adjacent portions of the metal caps, the cooperating surfaces in contact at each of said pivotal connections being so shaped that each contact area is of an order of not morethan line contact, whereby the entire current may be transmitted from one cap to the other directly by said links.

2. The invention as set forth in claim 1, wherein at one of said pivotal connections the contacting surfaces of adjacent current-carrying elements conform to different radii of curvature.

3. The invention as set forth in claim 1, wherein at one of said pivotal connections the parts held in engagement by said spring means are so shaped that one contact surface is substantially plane and the other has a small area projecting beyond the main portion thereof to restrict the current-passing area of contacting parts.

4. The invention as set forth in claim 1, wherein at one of said pivotal connections one of said contacting surfaces is substantially plane and the other contacting surface is a surface of revolution.

5. The invention as set forth in claim 1, wherein at each of said pivotal connections one of the current-passing members is formed of a relatively soft metal and the other member is formed of a relatively hard metal.

6. In a high potential switch, a stationary insulator, a pivoted insulator, and pivoted links to pass current from the stationary insulator to the pivoted insulator, said links being so shaped that of the two adjacent surfaces in contact, one

is substantially plane and the other has a small area projecting beyond the main portion thereof to restrict the current-passing area of engagement between said links.

7. In a high potential switch, a stationary insulator, a pivoted insulator, and pivoted links to pass current from the stationary insulator to the pivoted insulator, said links being of relatively hard and soft metal so shaped that of two adjacent surfaces in contact, one is substantially plane and the other has a small area projecting beyond the main portion thereof to restrict the current-passing area of engagement between said links.

8. In a switch, a pair of members, a blade element comprising a pair of plates whose adjacent pairs of ends are spaced apart to provide opposed and substantially parallel contact surfaces for engagementwith the opposite sides of the respective members, and means pivotally mounting said blade element on one of said members, the contact surfaces at the sides of one of said members being each a surface of revolution, whereby the contact area is restricted to an order of notin excess of line contacts.

9. The invention as set forth in the next preceding claim, wherein one of said contacting surfaces is relatively hard and has a relatively low thermal and electrical conductivity, and the second contact surface is relatively soft and has a relatively high electrical and thermal conductivity.

10. In a switch, a pair of terminal members. a blade member contacting with one of said members and adapted in closed position of said switch to pass current to the second member, one of said members comprising a bifurcated member for contact with the opposite sides of a cooperating member, and said bifurcated member and the cooperating member having in contact plane surfaces and curved surfaces of revolution which restrict the contact areas substantially to annular lines.

11. In a high contact pressure switch, a hinge member, a blade member pivoted thereto, a contact element, and a projecting contact surface on one of said members restricting the contact between said members to an order substantially less than that of the transversely alined portions of said members.

12. In a switch, a pair of terminal members and a blade including a portion pivotally supported on one of said members, the contacting portions of said blade and the one member on which the same is pivoted consisting of a plane surface and a curved surface of revolution.

13. A switch of the type including a pair of line terminal elements, and a blade pivotally connected to one element for movement into and out of engagement with the second 'line element, characterized by the fact that the contacting surfaces of said blade and the line element to which the same is pivotally connected have different radii of curvature, whereby the contact between the same is restricted to the order of line contact.

14. In a switch, the combination with a pair of terminal elements, a blade pivoted on one of said terminal elements and adapted to contact the second terminal element to close said switch, and means restricting the area of contact between said blade and each of said elements to the order of not substantially in excess of line contact.

CARL G. KOPPITZ.

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