US2273069A

US2273069A - Disconnecting switch

Info

Publication number: US2273069A
Application number: US160520A
Authority: US
Inventors: Allen M Rossman
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-08-23
Filing date: 1937-08-23
Publication date: 1942-02-17
Anticipated expiration: 1959-02-17

Description

Feb. 17, 1942. A. M. RossMAN DISCONNECTING SWITCH 4 sheets-sheet 1 Filed Aug. 25,' 193? INVENTOR. //en M @oss/77077 ATTRNEY.

Feb. 17, 1942.

A. M. ROSSMAN DISGONNECTING SWITCH Filed Aug. 25, 1957 4'Sheets-Sheet 2 INVENTOR.

//en M. @oss/77cm ATTORNEY.

Feb. 17, 1942. A; M. RossMAN 2,273,069

. DIscoNNE'cTING swITcH Filed Aug. 2s, 1937 4 sheets-sheet 5 ATTORNEY.

Feb. 17, 1942. A. M, RossMAN DIscoNNEcTING swITcH Filed Aug. 23, 1937 4 Sheets-Sheet 4 l AINVENT OR.

//en M. @oss/nah ATTORNEY.

Ji/m8. @Y

El w8 n@ mi m mi E QS Y stations of the enclosed type.

Patented Feb. 17, 1942 UiTE STATES 17 Claims.

This application is a continuation in part of my pending application, Serial No. 97,541, iled August 24, 1936, now Patent 2,218,554 dated October 22, 1940.

'I'he present invention relates to electric disconnect switches and more particularly to air break disconnect switches as distinguished from the'oil immersed type. It is one of the objects of the present invention to provide an air break disconnect switch which will be exceedingly compact and which will require a minimum amount of space for the movement of the movable contact making member from its circuit closed to its circuit open position, and which will require a minimum clearance space for the switch when the movable element thereof is in its alternate positions.

Ihe teachings of the present invention are particularly applicable to switches for use in medium-high voltage power systems. The principles of the present invention are also particularly applicable in sub-stations, particularly sub- 'I'he design of air break disconnecting switches heretofore used in electric sub-stations has been such as to require a good deal of space. In accordance with the teachings of the present invention the disconnecting switch is so constructed and arranged that the blade moves in such a way as to require a clearance space as it travels from its switch closing position to its switch open position. This result is accomplished by constructing the blade and part of the actuating means therefor so that the movable switch element in effect telescopes upon itself as it moves to its switch open position. Because of this switch structure it is possible to make a large part of the enclosed switchgear as a complete unit which can be shipped from the factory fully assembled.

In the preferred form of switch of the present invention the blade or contact making member is of the type which moves in a straight line between its alternate positions. The contact making member is movably mounted on a movable carriage and is so connected to the carriage that movement of the carriage in a straight line causes a like movement of the blade or contact making member at double the carriage speed. In one form of this invention the carriage comprises essentially a wheeled frame mounted on the switch supporting structure and carrying a switch blade, sui-table gearing being arranged between the carriage, the stationary switch structure, and the blade so that upon movement of the carriage with respect to the stationary structure the blade moves with the carriage, and the gearing also imparts a movement to the blade with respect to the carriage so that the total movement of the blade is twice that of the carriage itself. In one embodiment of my invention the gearing between the movable contact making member, the carriage, and the stationary portion of the switch comprises one or more rollers and means cooperating with the rollers, the blade, and the stationary structure for moving the blade with respect to the carriage in response to movement of the carriage. This means may comprise a belt looped around a wheel or pulley carried by the carriage and connected at one place to the stationary structure and at another place to the contact making structure so that upon movement of the carriage and corresponding movement of the wheel or pulley around which the laminated belt is wound, the belt moves the contact making member with respect to the carriage. The belt may comprise a stack of exceedingly thin laminations of copper strips, say each of a thickness of approximately 0.005 inch, the stack being built up to a suicient thickness to carry the current for which the switch is designed. The laminated belt, therefore, constitutes a means for carrying the current from one stationary switch terminal to the switch blade or switch Contact making member without sliding contacts so that the only sliding contact in the switch is between the movable contact making member and the stationary contact that is engaged thereby in the switch closed position. Where the current carrying capacity of the switch is so great as to require an inordinately thick stack of laminations to carry the requisite current there is provided a plurality of laminated belts, each of which carries a fraction of the total switching current, thereby maintaining the resiliency of each belt to iiexing.

The rollers, which constitute a part of the gearing between the movable carriage, the stationary structure and the contact making member, also constitute the means for holding the laminated conductor that extends from the circuit to the switch blade, taut. The circuit from one switch terminal to the movable switch element is extended to the laminated belt at the point where the belt is permanently connected to the stationary structure, and thence the current divides through the belt, half of it ilowing in one direction and half in the other, to the point where the belt is connected to the movable Contact making member, the equal division being obtained because the two paths have substantially the same resistance and inductance.

It is another object of the present invention to provide a switch of the above mentioned character wherein most of the metal elements of the switch are of standard structural shapes so that the parts for assembling a switch can be readily obtained without the need of making special patterns, castings, or the like.

The attainment of the above and further objects of the present invention will be apparent from the following specification taken in conjunction with the accompanying drawings forming a part thereof.

In the drawings:

Figure 1 is a longitudinal sectional View of a horizontally movable disconnect switch constructed in accordance with the teachings of the present invention, with certain of the parts broken away to illustrate the interior of the switch;

Figure 2 is a sectional view taken along the line 2-2 of Figure 1; i

Figure 3 is a sectional View taken along the line 3-3 of Figure 1;

Figure 4 is a fragmentary sectional view through one of the supporting wheels of the carriage of the disconnect switch;

Figure 5 is a fragmentaryview taken along the line 5-5 of Figure 4;

Figure 6 is a diagrammatic View of the switch in its open position;

Figure 7 is a diagrammatic view of the switch in its closed position;

Figure 8 is a top plan view illustrating an alternate construction, a portion thereof being omitted and other parts being broken away in order more fully to illustrate the construction;

Figure 9 is a side View of the switch shown in Figure 8, with certain of the parts omitted;

Figure 10 is a fragmentary sectional View taken along the line Ill-III of Figure 9;

Figure 11 is an enlarged fragmentary sectional view showing a portion of the movable contact making member in engagement with the stationary contact member of the switch of Figures 8 and 9;

Figures 12 and 13 are views corresponding, respectively, to Figures 8 and 9, and showing an alternate construction; and

Figure 14 is a sectional view taken along the line I4-l4 of Figure 13.

Reference may now be had more particularly to Figures 1 to 7, inclusive, which illustrate one embodiment of a switch constructed in accordance with the present invention. The switch shown in Figure l is adapted to be mounted in a switchgear such as is shown, for instance, in my aforesaid pending application, Serial No. 97,541, The switch comprises a tubular body which yeX- tends through a hole in the wall of the switchgear and is secured to the wall of the switchgear. The switch is indicated in general by the reference numeral I and is adapted to extend through and be mounted on the rear wall of a bus compartment, a fragmentary portion of which rear wall is indicated at 2 in Figure 1. In one end of the tubular body of the switch is mounted a stationary contact, and in the other end is mounted a carriage that supports a movable contact that is movable horizontally within the tube into and out of engagement with the stationary contact. The outer supporting casing is cylindrical and is made of suitable insulating material. The supporting casing comprises an inner tube of insulation 3 in the forward end of which is secured a conducting bar 4 by means of suitable screws or the like 5 that terminate flush with the outer periphery of the tube 3. An intermediate tube of insulation 6 fits snugly over the tube 3 and covers the ends of the screws 5 that hold the conducting bar 4 in position. A terminal 'l is bolted to the forward end of the conducting bar 4 and is adapted to have a circuit conductor bolted or otherwise secured thereto.

A movable member of copper or other high conducting material in the form of a tube I0, longitudinally slit at the top, is supported within the insulating tube 3 on two pairs of rollers II and I2 so that the movable member I0 can ride forward and backward within the tube 3. The rear end of the movable member carries a copper ring I4 within which are bound a series of spring contact fingers I5 which are clamped in place by a ring I6. The fingers I5 constitute the female contact of the switch. The ends of the fingers I5 are pressed inwardly by coil springs I8 and I9 so that the female contact rmly grips the male contact. A plate 2U closes the forward end of the movable member I0.

A movable carriage is mounted within the movable member I 0. The carriage comprises a pair of

pulleys

22 and 23 secured together on their opposite sides by tie bars 24 which maintain the pulleys a xed distance apart but permit free rotary motion of the pulleys. A laminated endless copper belt 25 is wound around the

pulleys

22 and 23. The belt is made of a large number or stack of exceedingly thin laminations of copper or the like, sothat the belt is exceedingly flexible. The belt is welded to the member I9 at 28 and is welded to the bar 4 at 29. The

points

28 and 29 are spaced apart a distance substantially equal to half the entire length of the belt 25 so that when current flows through the belt from the point 29 to the point 28 it iiows over two paths in parallel and of substantially equal resistance and inductance. The carriage, including the

pulleys

22 and 23 and the tie bars 24, may be advanced or retracted by pulling on an insulating rod 30 that is connected to the forward end of the pulley tie bars 24. Belt and pulley guides 26 are secured to the tube I0 for guiding the carriage. As the carriage moves forward, the point 29 remains stationary, being welded to the stationary bar 4 and therefore the

pulleys

22 and 23 roll in a counter-clockwise direction within the belt. The belt thus moves the tube Ill forward since the point 28 on the belt is welded to the tube IIJ. It is apparent from the construction thus far described that the speed of travel of the tube II] will be just twice the speed of travel of the carriage within the tube. The female contact carried at one end of the tube I0 is thus moved rearwardly within the tube 3 until it engages a stationary contact 35 mounted in the rear of the tube 3. An electrical connection is thus established between the terminal 'I and the contact 35, said connection extending from the terminal l, through the conductor bar 4, to the point 29 where the laminated belt 25 is welded to the bar 4, thence in opposite directions along the belt 25 to the point 2B Where the belt is welded to the tube Ill, thence by way of the tube i0, to the female contact I5, which isin engagement with the male contact 35. It is to be noted that the flexible connection between the female contact I5 and the stationary bar 4 is taut at all times, and there is no sliding connection between the female contact and the terminal 1 of the switch. In this disconnecting switch the only sliding engagement is the one between the male and female contacts. The

pulleys

22 and 23 hold the belt 25 in its normal shape at all times, fix the minimum diameter around which the belt is bent or exed, and assist in keeping the movable contact member in a straight line path of travel, and assist driving the tube IB forward and backward.

At the rear of the bar 4 there is provided a similarly shaped bar 31 of insulation, in alignment with the bar 4 to guide the belt as the carriage is moved towards its switch closed position. Insulating tubes 39 and 40 are secured over the forward and rear ends of the outer tube 6 on opposite sides of the wall 2 of the compartment within which the switch extends. The ends of the

tubes

3, 6 and 45 opposite the contact 35 are cut away, as indicated at 4l, to permit inspection of the contacts when they are in engagement. A sliding tube of insulation 42 is provided at the rear end of the switch, which tube may be slipped to the right from the position shown in Figure l so that it covers the opening lli. When this is done the entire disconnect switch is a closed unit fully insulated and adequately protected. The only exposed live parts are the terminal 'l for receiving one line connection and a stud 44 for receiving another line connection. If any one of the laminations of the belt should break, there is no possible danger that it will extend beyond the female contact in a direction towards the male contact, since the rear end of the carriage is entirely closed by the closures I4 and 2li. By reason of the two insulating

tubes

3 and 6, instead of a single tube of their combined thickness, the heads of the screws 5 are covered by the insulating tube 6 so that the creepage distance from the screws to the grounded supporting frame 2 which surrounds the tube 6 is Very greatly increased.

Reference may now be had more particularly to the switch shown in Figures 8, 9 and 10. This switch comprises a grounded metal mounting base 59 at one end of which is rigidly mounted an insulator 5I that supports the stationary switch contact, and at the other end of which is mounted a rotary insulator 52 and a stationary insulator 53 which support the contact switch blade for the movable contact making member of the switch. The insulator 52 is mounted upon the base 55 by means of a suitable bearing, the spindle of which supports the insulator and extends through the base where it is connected to a crank 5d whereby the insulator 52 may be rotated in a manner well known in the switching art. The tops of the

insulators

52 and 53 are joined together by a bracing member 55, preferably of non-magnetic material, which is rigidly bolted to the insulator 53 and which is connected to the insulator 52 by means of a suitable tudinally extending inwardly facing channel shaped side rails $8 and Si of non-magnetic material. A carriage 62 is mounted between the side rails 68 and 6l and supports the switch blade 53, which blade is movable with respect to the carriage. horizontal plate B5 and a lower horizontal plate 56 each of substantially a rectangular shape and preferably of non-magnetic material. The plates and 66 carry four wheels or pulleys 68, Bil, 'i8 and 1|, which are spaced from the plates by suitable spacers 72 and are freely rotatable about their respective axes. The switch blade or contact making member comprises two parallel outwardly facing non-magnetic channel members 'i4 and 'l5 secured together in spaced relationship by a pair of spacers l5 and '51. The circuit is extended from the stationary terminal of the switch by means of two stacks of exceedingly thin laminations of copper or the like, indicated at 88 and 8|, which extend on the outsides of the F' The carriage comprises an upper l channels and 6l to approximately the mid points of the channels. The laminated stack extends through a slot in the web of the channel 68 to the inside of the channel where the stack is divided in two, half of the laminations then extending, as indicated at 83, around the pulley 89 thence along the inside of the channel 1 4 to a. slot 85 Where the laminations 83 extend through the channel 'le to the outside of the web of the channel. The other set of laminations of the stack 80, indicated at 86, extends around the pulley 'i l, thence along the inside of the channel T4 to the slot 85 of the channel, Where that group of laminations extends through the channel 'I4 and is joined with the group of laminations 83. extends along the outside of the channel 6| to an opening 81 in the channel, thence through that opening, where the group of laminations is divided, half of the laminations extending at 88 along the inside of the channel 6! thence around the pulley 88 and along the insidev of the channel 'l5 to an opening or slot 89, where it extends through the web of the channel l5. The other half of the laminations of the stack 8|V extend through the opening 87, around the pulley 10, thence along the inside of the channel 15, as indicated at 50, to the opening 89, where they join with the group of laminations 88. 'Ihe laminated conductor 92, which is a consolidation and continuation of the laminated conductors 80 and 8l, or a consolidation of the two laminated belts around the sets of pulleys 68-70 and (S9-ll, extends between the two channel members 'I4-75 for the full length of the switch blade. At the forward end of the blade the mass of laminations is again divided, half of the group being indicated at and the other `half at 96.

The slots 8l and 89 are so located with respect to one another that the length of the lamina.- tions 88 between the slots and around the pulley 68 is substantially equal to the length 80 around the pulley l0. The same is true of the laminations extending around the pulleys 58 and ll. The belts or loops of laminations around the pulleys are maintained taut by the pulleys. The

pulleys

58 and 70 ride between the flanges of the channels 6l and 15, and the pulleys 6,9 and 'H ride between the flanges of the channels 68 and lll. The carriage 82 is thus supported from the flanges of the channels 60 and 6i by the pulleys, and the pulleys in turn support the switch blade 83. The carriage is free to roll between the flanges ofthe channels 68 and 5I and is moved forward and backward by means of the crank 58 which is connected to. the carriage by a link 93. In its. rolling movement it imparts motion to the switch blade in a manner similar to that of the switch of Figure. l, previously set forth.

The forward end of thev blade has a contact making portion formed thereonfor establishing circuit connections with the stationary contact of the switch. The U-shaped spacer 'Il includes a portion 94 interposedbetween the groups of laminations 55 and d6 to keep them spread apart.

The laminations are maintained spread apart by a series of springs 9i so that they bear against the inside of a keeper 98 that is secured to the forward end of the switch blade, the groups of laminations 95--96 being free to move away from the keeper, that is, towards one another. against the action of the springs 9i'. Each group of

laminations

95 and 95 has a number of contact making studs 89 secured thereto, in this instance sixteen studs for each group of lamina- The laminated conductor 8l likewise` in Figure ll.

tions, as may be seen from Figure 9, the studs being arranged in horizontally extending rows vertically spaced from one another. The stacks of

laminations

95 and 96 are slit between the rows of studs, as indicated at |90, to improve the resiliency of the stacks.

Each of the contact studs is secured to the laminations in a manner illustrated more fully For that purpose the group of laminations 90 are clamped together and drilled and tapped to receive the threaded end of a contact stud 99. The stack of laminations is then heated adjacent the tapped hole and the threads are then tinned. While the stack of laminations is still hot and the tin still plastic, the stud 99 is threaded through the treads in the tapped hole in the stack of laminations 95 so that it extends through the stack of laminations, as illustrated in Figure 11. Thereafter upon cooling of the tin or solder, a firm electrical engagement is had between the stack of laminations and the contact stud 99. Each stud 99 extends freely through an oversized hole in the keeper 98. The springs 91 maintain the stacks of laminations and the contact studs in their extreme outer position with respect to the keeper 98. When the blade is moved into engagement with the stationary contact member, the studs 99 are forced inwardly a small amount, and the springs 91 maintain a firm electrical engagement between the contact studs and the stationary contact. The contact making ends of the studs 99 are silver plated to increase the conductivity between the studs and the stationary switch contact.

The stationary contact of the switch is indicated at and comprises two prongs outwardly llared at their end to receive the contact studs 99. As the switch is actuated to its closed position, in a manner to be presently set forth, the contact studs move between the prongs of the stationary contact |0| and are forced inwardly a slight amount against the action of the springs 91. Each pair of contact studs has an individual spring 91, there being sixteen such springs in the switch illustrated in Figures 8 and 9, so that each spring maintains its individual pressure against the associated pair of contact studs and thereby maintains the associated pair of contact studs in rm pressure engagement with the stationary contact member. Due to the extreme resiliency and flexibility of the stacks of laminations 95-96 there is sufficient give or ilexibility in the stack of laminations betwen adjacent contact studs to permit each spring 91 to force its associated contact studs into rm pressure engagement with the stationary contact |0|, without regard to the action of any of the other contact studs.

An explanation will now be given of the mode of operation of the switch illustrated in Figures 8, 9 and 10. Upon rotation of the insulator 52 by turning of the crank 54, the crank 58 is turned, thereby actuating the link 93' to move the carriage 62 rearwardly between the channel frame 60-6|. The four rollers or pulleys {S8-1| thus ride in the channels and cause the two belts to roll and thereby impart longitudinal motion to the switch blade 63, the blade moving at twice the speed of the carriage, and thereby moving exactly twice the distance that the carriage moves. When the contact making structure engages the prongs of the contact I0| each of the contact studs 99 is moved inwardly a small amount by the prongs |0| against the pressure of the springs 91 as previously set forth, and the contact studs thereby establish rm pressure engagement with the prongs 0|. The switch opening movement is exactly the reverse of the switch closing movement above set forth,

as will be apparent from the description thus far given.

Reference may now be had more particularly to the switch shown in Figs. 12, 13 and 14. Here, as in the switch of Figure 9, there is provided a grounded base 50, a stationary contact supporting insulator 5| and a pair of

insulators

52 and 53 for supporting and actuating the movable contact making member, of which the insulator 52 is mounted for axial rotation by means of a crank 54, as in the switch of Figure 9 previously described. 'The switch of Figure 13 is of lesser width than in the switch of Figure 9. The rotary insulator 52 and the stationary insulator 53 are joined by a bracing plate |20 which is rigidly bolted to the insulator 53 and which is connected to the insulator 52 by means of a bearing, like the bearing 56 of Figure 10, whereby the insulator 52 may rotate axially with respect to the bracing plate |20. The bracing plate |20 has a vertical plate |2| bolted or otherwise rigidly secured to the plate |20 at one longitudinal edge thereof, as is apparent from Figures 12 and 14. An inwardly facing longitudinally extending channel bar |23 is suitably bolted to the plate |2| adjacent the top thereof. The channel |23 constitutes a guideway for one side of a laminated conducting belt, to be hereafter described, and also a support for one side of the movable carriage. Along its forward edge the bracing plate |20 has a plurality, in this instance three, of standards |25 secured thereto, each of which standards supports a roller |26 at its upper end, the rollers being swiveled to turn freely about their axes on the standards |25.

A laminated copper conductor` |40, consisting of exceedingly thin continuous strips of copper each of a thickness of about 0.005 inch, is secured to the outside of the plate |2| and extends through a slot |42 in the plate |2| and in the channel |23, to the inside of the channel where it is divided in two. Half of the laminations, indicated at |43, pass rearwardly in the trough of the channel |23 and around the pulley |34, while the other half |44, extend forwardly in the trough of the channel |23 and around the pulley |35, thence the two groups of laminations |43 and |44 extend in the inner trough of the I-beam |38 to a slot |41. Here the groups of laminations are again joined and then they extend to gether forwardly, within the outer trough of the I-beam |38, as indicated at |48, to a contact making head |49 that is secured to the forward end of the I-bearn |38. 4The rollers |26 press the stack of laminations |48 rmly against the I- beam |38. A female contact making member |50 is secured to the forward end of the Contact making head |49 and in good electric engagement with the end of the stack of laminations |48. The female contact making member cooperates with a male or stationary contact that is mounted on the stationary insulator 5| and in proper conductive relationship to a bus |52 or other suitable switch terminal.

The switch is actuated by means of a spur gear |55 that is rotated by rotation of the insulator 52, said gear being rigidly secured to a spindle carried by the head of the insulator 52 and extending through a suitable rotary bearing in the manner illustrated in Fig. 10, for example. The gear |55 meshes with a similar gear |56 carried on the bracing plate |29. A crank arm |57 is secured to the gear |55 and is rotated thereby, the crank alm actuating a link |58 which is pivoted at one end to the crank arm and at its opposite end to the bar |32 of the carriage |30.

The operation of the switch is as follows: Upon rotation of the insulator 52 by the crank 54 the gear |55 turns the gear |56, which turns the crank |51 to actuate the link |58 to move the carriage |30 forward. As the carriage moves forward, the rollers |34 and |35 are moved forward bodily and thus rotate in a direction counter-clockwise as seen in Figure 12, so that the roller |34 rolls forward on the belt |43 While the roller |35 rolls forward on the belt portion |44 and move the top portion |44 progressively further forward in the channel` |23. The belt |43 thus rolls in the trough of the channel |23, the portion of the belt at |42 remaining stationary. This forward rolling movement of the belt causes the I-beam or blade structure |38 to move forward at a speed which is twice the speed of the carriage |30, and a distance which is twice the distance of travel of the carriage |30. During this movement the belt or loop formed by the conductor portions H13-|44 is kept taut, and the rollers |26 maintain the laminated conductor |48 in the outwardly facing channel of the I- beam |38. The contact |50 is thus moved into engagement with the contact |5|, the distance of movement of the contact-making member |50 being twice the distance of movement of the carriage |35.

The gears |55 and |55 are introduced in order to permit the use of a longer crank arm |51, without increasing the width of the structure. If a shorter crank arm were used, then the movement imparted thereby to the link |53 would be insufficient to move the contact making member the requisite distance. The gears |55 and |55 are not necessary in the structure of Figure because in this structure the switch is of appreciably greater width, thereby allowing the use of a longer actuating crank on the head of the insulator 52, without increasing the overall width of the switch.

In the switches of Figures 9 and 13, all of the operating structure above the link 33 or the link |58, is preferably of non-magnetic material. The parts of the switches on which the belts of laminated strips roll, namely the channels 60--65 and the channels 'i4-'l5 of the switch of Figures 8-11, and the channel |23 and the I-beam |38 of the switch of Figures 12-14 are preferably made of insulating material to prevent the division of current therethrough and coniine all the current to the laminated conductor. If those parts are made of conducting material (non-magnetic) an insulating strip of bakelite or the like is preferably interposed between the laminated conductor and the inside of the channels in which the laminated conductor rolls. This is desirable to prevent the flow of largel currents between the belt and the supporting channels, as during short circuit conditions, for such large currents may cause the laminations to become welded to the channels, or welded together.

In compliance with the requirements of the patent statutes I have here shown and described a preferred embodiment of my invention. It is, however, to be understood that the invention is not limited to the precise construction here shown, the saine being merely illustrative of the principles of the invention. What I consider new and desire to secure by Letters Patent is:

1. An electric switch including a member mounted for rectilinear movement, a contact making member associated with the iirst member and movable therewith, means responsive to movement of the first member for moving the contact making member rectilinearly with respect to the iirst member in the direction of movement of the rst member whereby the speed of the contact making member is the sum of its speed with respect to the first member plus the speed of the first member itself, said means including gearing one part of which is carried by the first mentioned member and is rotated by rectilinear movement thereof, and a driving connection between said rotated part and the contact making member, said driving connection including a flexible conductor looped over said rotated part and mechanically connecting the contact making member with a stationary portion of the switch.

2. An electric switch including a member m-ounted for rectilinear movement, a contact making member associated with the rst member and movable therewith, means responsive to movement of the first member for moving the Contact making member rectilinearly with respect to the rst member in the direction of movement of the rst member whereby the speed of the contact making member is the sum of its speed with respect to the rst member plus the speed of the first member itself, said means including gearing one part of which is carried by the first mentioned member and is rotated by rectilinear movement thereof, and a driving connection between said rotated part and the contact making member, said driving connection including a iieXible belt of conducting material looped over said rotated part, means for keeping the loop taut, a mechanical and electrical connection between one part of the 'belt and the contact making member, means holding another part of the belt stationary, said two parts of the belt being apart on said looped belt.

3. An electric switch including a pair of switch terminals and a contact making member movable into and out of circuit establishing connection between them, an electric connection between one of the terminals and the member comprising a pair of spaced wheels and a flexible copper belt tautly looped over the wheels, one point on the belt being secured to said one of the terminals and another point being secured to the contact making member.

4. An electric switch including a pair of switch terminals and a contact making member movable into and out of circuit establishing connection between them, an electric connection between one of the terminals and the member comprising a pair of spaced wheels and a flexible copper belt tautly looped over the wheels, one point on the belt being secured to said one of the terminals and another point being secured to the contact making member, the two points being spaced from one another half the distance around the belt.

5. An electric switch including a supporting structure, a Contact making member supported thereon and movable in a straight line from its switch open position to its switch closed position, a flexible conductor secured to the supporting structure and to thev member, and means for maintaining the conductor taut in every position of the member from its open to its closed positions, said means comprising a pulley around which the conductor is looped a fraction of a turn, said pulley having rolling movement along the supporting structure.

6. An electric switch including a stationary structure, a switch terminal carried thereby, a flexible conductor in the form of a closed loop secured at one point to the stationary structure and capable oi rolling with respect to said structure while maintaining said one point fixed with respect to the structure, a contact making member movable in a straight line, another point on said loop being fixed to the contact making member, and means for holding the loop taut whereby the contact making member is actuated by the loop as the loop is rolled with respect to the stationary structure.

7. An electric switch including a stationary structure, a switch terminal carried thereby, a flexible conductor in the form of a closed loop secured at one point to the stationary structure and capable of rolling with respect to said structure while maintaining said one point ixed with respect to the structure, a Contact making member movable in a straight line, another point on said loop being fixed to the contact making member, and means for holding the loop taut whereby the contact making member is actuated by the loop as the loop is rolled with respect to the stationary structure the two points on the loop being so spaced from one another as to divide ther loop into two parts having like electrical characteristics.

8. An electric disconnect switch comprising a supporting structure, a carriage mounted for rectilinear movement in said structure, a contact making member carried by said carriage and movable thereby, means for moving the carriage, and means responsive to the movement of the carriage for moving the contact making member at a speed with respect to the carriage which is at least equal to the speed of the carriage with respect to the supporting structure, and in the same direction, so that the contact making member moves at least twice as far as the carriage.

9. In an electric disconnect switch, a movable carriage, rollers for guiding the carriage secured thereto on opposite sides thereof, the rollers on opposite sides oi the carriage lying in substantially the same plane, and a contact making member carried by the carriage and guided between said rollers.

10. In an electric disconnect switch, a movable carriage, rollers for guiding the carriage secured thereto on opposite sides thereof, the rollers on opposite sides of the carriage lying in substantially the same plane, a contact making member Vcarried by the carriage and guided between said rollers, and means for moving the contact making member with respect to the carriage, said means including at least one of said rollers.

1l. An electric switch including a switch terminal, a contact making member movable relative thereto, a iiexible conductor connecting the two, and means for maintaining the conductor taut as the contact making member moves, said means comprising a rotatable pulley movable axially with respect to the terminal and with respect to the contact making member, said conductor being looped around the pulley and means confining the axial movement of the pulley to a path parallel with the path of movement of the contact making member during a substantial part of the operative movement of the same.

12. A switching member comprising a exible stack of conducting laminations, a plurality of contact studs extending through the stack, a metal bond between each stud and the individual laminae of the stack, the stack being flexible between adjacent studs, and separate spring backing means for the respective studs, to permit individual angular movement of the respective studs.

13. A switch contacting member comprising a flexible stack of laminations, rows of contact studs extending through the stack at one end thereof, and a relatively rigid member extending along an end lamina, the studs passing loosely through holes in the member.

14. A switch contacting member comprising a flexible stack of laminations, rows of contact studs extending through the stack at one end thereof, the stack being slit between adjacent rows of studs to permit individual relative movement of the respective studs, and means inhibiting excessive relative movement of the studs.

l5. A switching member comprising a stack of laminations of conducting metal, a plurality of side by side spaced contact studs secured to the stack, and individual pressure exerting springs for the respective studs, said stack of laminations being sufliciently flexible between adjacent contact studs to permit relative movement of the studs by the respective springs.

16. A switching member comprising two side by side spaced groups of flexible stacks of laminations of conducting metal, a plurality of adjacent contact studs secured to each stack, springs between the stacks urging the stacks apart, means limiting the spreading of the stacks, said studs extending through said limiting means and movable therethrough against the action of springs.

17. Switching means comprising a contact, a laminated contact making member movable into the contact and having a plurality of studs projecting from each of the opposite sides thereof into engagement with the contact, the studs being in relatively movable pairs with one stud of each pair projecting from one side of the contact making member and the other stud vof each pair projecting from the other side of the Contact making member, the studs of each pair being relatively movable, and a separate spring associated with each pair of studs and urging them outwardly of the contact making member.

ALLEN M, ROSSMAN.