US2547413A

US2547413A - Connector bar

Info

Publication number: US2547413A
Application number: US52245A
Authority: US
Inventors: Wayne R Scherer
Original assignee: Taylor Fibre Co
Current assignee: Taylor Fibre Co
Priority date: 1948-10-01
Filing date: 1948-10-01
Publication date: 1951-04-03
Anticipated expiration: 1968-04-03

Description

W. R. SCHERER CONNECTOR BAR April 3, 1951 2 Sheets-Sheet 1 Filed Oct. 1, 1948 ows/vrm Wayne R. Scherer ITIU/PIYF VS April 1.951 w. R. SCHERER 2,547,413

CONNECTOR BAR Filed Oct. 1, 1948 2 Sheets-Sheet 2 58 INVENTOR.

f ay/v5 R. SCHERER ATTORNEYS Patented Apr. 3, 1951 Uil STATES PTENT OFFICE Application October 1, 1948, Serial N0. 52,245

2 Claims.

This invention relates to an improvement in connector bars.

Connector bars are provided in circuit breakers, which find various uses, as, for example, in switch mechanism; and, mounted for rotation, carry contacts for the making and breaking of circuits.

As is well known, connector bars have heretofore been formed from metal, as steel, and of substantial size, since they are subjected to considerable torque due to the rapid opening when the circuit is broken. The metal bar is covered with an insulating material, as fabric or paper, impregnated with a synthetic resinous material, as a phenol formaldehyde resin, which is molded to the contour of the bar, which is usually four sided. The contacts are clamped to the bar outside of the insulating covering, which extends somewhat beyond the end of the metal bar to enable the ends to be sealed with insulating material.

Connector bars as heretofore made have been open to various objection in that no means are provided to insure against endwise movement of the metal bar in the insulating covering, beyond the frictional engagement of the covering with the bar; and their production has only been accomplished by separately wrapping the bars.

Now in accordance with this invention from the product standpoint, a connector bar, of the type indicated, is provided of such construction that the metal bar is positively held against endwise movement;v while from the method standpoint procedure is provided whereby a plurality of the bars of the novel construction may be wrapped simultaneously with accuracy and dispatch.

Having now indicated, in a general way, the nature and purpose of this in'ention, I will proceed to a detailed description of a preferred embodiment of the product and of preferred procedure for the production thereof, all with reference to the accompanying drawing in which:

Figure l is a side view of a plurality of connector bars assembled for wrapping with insulating material.

Figure 2 is a side view, partly in section, of a bar on completion of the wrapping,

Figure 3 is an end view of the subject of Figure 2.

Figure 4 is a side view, partly in section, after molding of the insulating wrapping to the bar.

Figure 5 is an end view of the subject of Figure 1.

Figure 6 is a side view, partly in section, of com leted connector bar.

Figure 7 is a sectional view on line 'l-'l, Figure 6.

Figure 8' is a sectional view on the line 88 of- Figure 10, showing a connector bar in a circuit breaker with the switch in an open position.

Figure 9 is a similar view showing the switch closed.

Figure 10 is a View looking in the direction indicated by the arrow in Figure 8.

The connector bar according to this invention, shown in Figures 6 and '7, comprises a metal bar A, of steel or any desired suitable metal, and square in cross-section, though the bar may have any suitable cross section, as, for example, circular, triangular, hexagonal, octagonal, or the like.

The bar A will be of suitable length for mounting in a circuit breaker and to carry the desired contacts and rocker arms between its ends.

Molded to the bar A, or otherwise closely conformed to the faces thereof, is an insulating material B, which may be a paper or fabric impregnated with a synthetic resin having insulating capacity, as, for example, a phenol formaldehyde type resin; and which may be applied by wrapping.

The insulating material, which is continuous, extends substantially beyond the ends of the bar A and is formed with a circular bore e so that it extends inwardly at the end of the bar engaging its end faces and forming the bore 6, thereby providing abutments for the ends and positively preventing endwise movement of the bar A in the insulating material. The outer surface of the insulating material beyond the ends of bar A forms an extension of the surface of the portion conformed to the bar.

The end portions 1) of the insulating material beyond the ends or the bar A may be plugged with insulating material or a disc of insulating material may be secured within the end portions 1) to prevent leakage of current to the end of the bar A from a contact carried by the bar.

The method according to this invention, for the production of contact bars of the structure described, will be made apparent by reference to Figures 1-5.

A plurality of approximately square metal bars A, bored and tapped at their ends, as at an, are assembled together, as shown in Figure 1, by means of circular rods 0 provided with reduced threaded ends d,d, for engagement in the tapped ends !a of the bars A.

The circular rods 0 will be of a diameter not in excess of, and desirably about equal to, the minor dimension of the face of the bar. If the bar A is circular, the rod 0 will be of less diameter than the bar.

A plurality of bars A having been assembled together, the assembly is mounted in any suitable mechanism, for rotation as' a mandrel, and sheets of insulating material B are wound upon the sev eral bars A. i

'I'hesheets of insulating material B,=as has been indicated, may be composed of any suitable material, as, for example, paper or fabric impregnated with a synthetic resin, as, for example, a phenol formaldehyde resin.

The sheets of insulating material B, will, as

shown in Figure 1, be of a width greater than the length of the bars A, so that when the sheets are wrapped upon the bars the wrapping will 'extend beyond the ends of the bars over a portion of the circular rods 0. p

The wrapping having been completed; the Wrapped bars A will appear as shown in Figures 2 and 3, from an inspection of which it will be noted that the insulating material B will conform to the faces of the bars throughout their length and will extend beyond the ends of the bars over the rods 0, being in contact therewith only along lines where the diameter of the rods equals the dimensions of the ends of the bars A.

The wrapped assembly is now placed in a mold conforming to the contour of the bars A and rods c and heat and pressure applied to compress and conform the insulating material B to the bars A and rods and to set the resin.

As shown in Figures 4 and 5, the pressure applied in the mold compresses the insulating material and conforms it to the faces of the bars A and, at the same time, conforms it to the circular rods 0. The portions of the insulating material conformed to the rods 0 are somewhat less dense than that conformed to the faces of the bars. However, such portions of the covering which extend beyond the metal bar extend inwardly across a portion of each end of the metal bar forming abutments for each end of the metal bar as shown at :1: in Figure 5.

When the molding is completed, the assembly is removed from the mold and finally the several insulated contact bars are unscrewed from the several rods 0, which are then available for the assembly of further bars to be wrapped.

In Figures 8-10, I have illustrated one form of circuit breaker provided with a connector bar such as shown in Figures 6 and '7 and in use with a circuit breaker provided with three contacts one being omitted at the left end in Figure 10.

Referring to Figure 8, the circuit breaker is mounted on a slab of insulation H], which, in turn, is mounted on a suitable support (not shown). The circuit breaker is provided with a supporting frame of U-shape for the actuating mechanism having a base l2 which is secured to the slab It, extending from each end of the base i2 is a flange 14 and extending from each flange I4- are arms l6 and [8. The upper ends of arms 18 are connected to each other by a cross bar 20 while the arms 15 are kinked as at 22 so that the upper portions of the arms it are closer to each other than the lower portions or flanges l4 as shown in Figure 10 and form stops for a spring carrying yoke 24 for the purpose hereinafter described. Extending outwardly from the flange Id at each side of the supporting frame between the arms i6 and It in the plane of arms l8 and the fianges M is a projection 26, one being shownin dotted lines in Figure 8. The yoke 24 is provided with an arm 28 at each side which extends toward the projections 26, each being mounted on a trunnion 33 extending inwardly from a projection 25 on which the yoke 24 is adapted to move from the position shown in Figure 8 until the arms 28 engage the inwardly kinked portions of arms it which are in the same plane as arms 28 (see Figure 10).

Connected to the arms is is a fixed shaft 32 and rotatably mounted on shaft 32 extending from one arm 18 to the other is a sleeve 34. Connected to the sleeve 34 intermediate its ends is an actuatinglever 36 having a handle 38 connected thereto. The outer end of lever 36 is provided with a keeper 4!] which is engaged by a latch 42 to retain the lever in the position shown in Figure 9 when the switch is closed. The actuating lever 38 is also provided with a projection 43 which engages bar 26 to limit the movement of the lever 36 in a counterclockwise direction.

Each movable contact 44 is adapted to be moved into contact with a fixed contact 4'6 mounted on the slab II), the movable contact being carried on one end of a lever 48, the other end of the lever having spaced projections 5!] which extend through an opening in the web 52 of a channel-shaped rocker arm 53 having flanges 54 extending from the web 52. The projections are pivotally mounted on a fixed shaft 56 connected to the flanges 54.

The flanges 54 of the rocker arm 53 are each provided with a square opening, through which the connector bar extends and is clamped in position against theweb 52 by a clamp 58 having projections 60 extending through openings in the web 52 and are riveted over the outer face of the web to firmly clamp the rocker arm in position on the connector bar. Extending from the contact carrying end of lever 48 is a fixed screw 62 which extends through a slot in the end of an extension 64 of the web 52 of the rocker arm 53, the end of the screw being provided with an adjusting nut 66 and a nut lock 88 for adjusting the position of the contact 44 relative to extension 64, and 19 is a spring surrounding screw 62 to maintain contact arm 48 spaced from the extension 6.

As previously stated, a circuit breaker such as illustrated herewith comprises three movable contacts each carried by a rocker arm 53 shifted by the movement of a connector bar, one of which rocker arms is located centrally of the connector bar within the supporting framefor the actuating mechanism between the arms 28 of the yoke 24 and one as shown at the right of the actuating mechanism as shown in Figure 10, the one at theleft 'not being shown.

a The central rocker arm 53 for the central movable contact is pivotally mounted on a fixed shaft it? which is fixedly connected to the flanges I4 of the frame of the actuating mechanism and extends through the flanges 54 of the central rocker arm 53, about the axis of which the three rocker arms, together with the connector bar A, are oscillated to close and open the circuit breaker as hereinafter described.

Pivotally connected to each side of actuating lever 36 at 14 is a link 15 which is pivotally mounted at the other end on a pin 18, the links being spaced from each other by a washer on the pin l8.

Fivotally mounted on the pin 78 at the outside of each link 14 is a link 82, the other ends of each link 82 are pivotally connected to shaft 56 connected to the flanges 54 of the central rocker arm 53-.

Pivotally mounted on the outer portion of each end of pin '18 is a walking beam 84. Extending from the connecting member of the yoke 24 are two projections 86, each being in the plane of a walking beam 84, each projection 86 being provided with two openings, while each Walking beam is provided with an opening in each end. Each walking beam 34 is connected to the projection in the same plane by two tension springs 88 whose ends extend through an opening in a walking beam and an opening in a projection 35, the arrangement of the springs resisting the movement of the rocker arms about the axis of shaft '52 in a countercloclw'lise direction or in the direction to close the circuit breaker and to place the actuating lever under a predetermined spring load to open the circuit breaker with a snapping action when the release mechanism withdraws the latch to permit the springs 88 to break the circuit.

In order to close the circuit breaker, the handle 38 is pressed downwardly to rock actuating lever 26 until the arms 28 of the yoke engage arms In of the supporting frame to the position shown in Figure 9, at which time the actuating lever 36, together with the walking beams, will be in the positions shown in dotted lines in Figure 9, (the springs 88 being omitted for clearness), in the further movement of the actuating lever 36, the rocker arms 53 will rotate about the axis of shaft 72, first closing the contacts and then compressing springs 10 as shown in Figure 9 at which time the actuating lever 36 will be locked by latch 42 to retain the circuit breaker in its closed position.

The leads from fixed contacts 46 as well as from levers 48 carrying movable contacts have been omitted for clearness. Connector bars of this character have been open to objection in that no means were provided to insure against movement between the metal bar and the insulating covering.

It is well known that bars of this type have been formed of steel of substantial size covered with insulation as they are subjected to considerable torque. When a number of contacts are connected to the covering of the bar in cases where there is the slightest movement between the bar and the insulating covering, a slight time lag is caused between the separation of adjacent switch contacts mounted on the same connector bar and the contacts with which they cooperate to open or close a circuit due to the torque to which the covering is subjected when the bar is rocked to open the switches which cause arcing between cooperating switch contacts due to the lag between adjacent contact carrying arms.

By the conforming of the insulating covering about the faces of the bar throughout the length thereof and about the end edges of the bar between the periphery of the bar and the rods about which the ends of the insulation are formed, all danger of starting separation of the insulating covering from the metal bar is avoided, as well as endwise movement of the bar in the covering, as the insulating covering is not only cemented to the entire periphery of the metal bar, but the portions of the covering extend over the ends of the bar between the periphery of the bar and the openings in the extending portions, so that the metal bar is gripped between the portions of the insulating covering extending over the ends of the metal bar.

This application is a continuation-in-part of my application Serial No. 574,121, filed January 23, 1945, now abandoned, which was a division of my application Serial No. 538,222, filed June 1, 1944, now Patent No. 2,446,490, issued August 1, 1948.

What I claim and desire to protect by Letters Patent is:

1. A rockable connector bar to which electrical switch contact carrying rocking arms are adapted to be clamped in spaced relation together with a connector bar rocking member under a predetermined spring load for snapping open the switches, comprising a metal bar having a continuous insulating covering extending beyond each end of the metal bar, said covering being molded to the outer face of the metal bar and across a portion of each end of the metal bar to resist movement of the insulating covering relative to the metal bar caused by torque due to the snapping action of the spring to which the connector bar is subjected while shifting the rocker arms by the connector bar rocking member when opening the switches.

2. A rockable connector bar to which electrical switch contact carrying rocking arms are adapted to be clamped in spaced relation together with a connector bar rocking member under a predetermined spring load for snapping open the switches, comprising a metal bar of rectangular cross-section having a continuous insulating covering extending beyond each end of the metal bar, said covering being molded to the outer face of the metal bar and across a portion of each end of the metal bar over at least the corners thereof to resist movement of the insulating covering relative to the metal bar caused by torque due to the snapping action of the spring load to which the connector bar is subjected while shifting the rocker arms by the connector bar rocking member when opening the switches.

WAYNE R. SCHERER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,963,856 Lewis et a1 June 19, 1934 2,439,084 Graves Apr. 6, 1948