US1278966A - Circuit-interrupter. - Google Patents

Description

J. N. MAHONEY & H. G. MAcDONALD.

CIRCUIT INTERRUPTER.

APPLICATION FILED NOV. 2a. 1913.

Patented Sept. 17,1918;

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INVEN 085 f 7 Q v ATTORNEY J. N. MAHONEY & HLG. MAcDONALD.

CIRCUIT INTERRUPTER.

APPLICATION FILED NOV. 28,1913.

Patented Sept. 17, 1918.

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UNITED STATES PATENT oEEIcE.

JOSEPH N. MAHONEY AND HOWARD G. MACDONALD, 0F WILKINSBU'RG, PENNSYLVANIA,

ASSIGNORS TO WESTINGHOUSE ELECTRIC AND MANUFACT CORPORATION OF PENNSYLVANIA.

CIRGUIT-INTERRUPTER.

To all whom it may concern:

Be it known that we, JosEPH N. MA- HONEY, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, and HOWARD G. MACDONALD, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania,have invented a new and useful Improvement in Oircuit-Interrupters, of which the following is a specification.

Our invention relates to electric-circuit interrupters and particularly to operating mechanism for the same.

One object of our invention is to provide an operating mechanism that requires a minimum space and which is adaptable to operate a plurality of circuit interrupters.

Another object of our invention is to provide a combined accelerating and retarding device for operating in combination with the operating mechanism.

In the prior art, multi-pole circuit interrupters have usually been provided with a plurality of operating electromagnets, uneconomically located with respect to the space occupied by the same.

According to our present invention, we provide a circuit interrupter having a single compact operating mechanism which may be located in front of any two adjacent poles of the same, and we also provide a combined accelerating and retarding device which insures a rapidly opening circuit breaker that is free from the jars and shocks which usually occur in devices of this kind. The entire mechanism of our invention is compact, simple and durable in construction, and its adjustable features make it especially adaptable to multipolar circuit interrupters.

In the accompanying drawings, Figure 1 is a front elevational view of a circuit interrupter embodying our invention. Fig. 2 is a side view, partially in elevation and partially in section, of the circuit interrupter shown in Fig. 1. Fig.3 is a front elevational view of an operating mechanism embodied in our invention. Fig. 4 is a side View, partially in section and partially in elevation, of the operating mechanism shown in Fig. 3, and Fig. 5 is a sectional View of an accelerating and retarding device embodied also in our invention.

Specification of Letters Patent. Patented Sept. 1"? 1918 Application filed November 28, 1913.

Serial No. 803,614.

Referring to I the drawings, the circuit breaker here shown comprises, in general,

- bers 8; mam movable contactmembers 9,

and auxiliary movable contact members 10, mounted upon the ends of a bridging member 11 and arranged for cooperative engagement with the above mcntionedstationary contact members 7, and an operating rod 12 located in a relatively central position with respect to the conducting terminal members 8 and connected" to the bridging member 11 by any suitable means. The conducting terminal members 8- are insulated from a supporting base member 13 by insulating bushings 14:. A receptacle 15, containing oil in which are immersed the cooperative contact members, is attachedto an expansion chamber 16 suspended from the underside of the supporting base member 13.

The single pole circuit breakers 1, 2 and 3 severally comprise a. crank arm 17 keyed to a shaft 18 which is common to all of the said circuit breakers. One end of the crank URING COMPANY, A

arm 17 is pivotally connected to one end of a link 17, the other end of which is pivotally connected to one end of a bell crank lever 19. The lever 19 is pivotally mounted by a detachable frame 26 and comprises, in

detail, an electromagnet 27 having a winding 28, and a movable core member 29 which is operatively connected, by a link 30, to a Y crank arm 31 that is keyed to the shaft 18.

1 The core member 29 is provided with a tightly fitting pliable washer member 29 'upon its lower end, for reasons hereinafter set forth. A saddle link member 32 is pivotally attached to the link by a pin 33. At an intermediate point on the link member 32, is pivotally attached one end of a. guide link 34, the other end of which is pivotally mounted upon a projection 35 on the frame 26. The link 32 is provided with an eye 36 at its upper end to receive a latch mem ber 37 that is pivotally supported by a pin 38 mounted between trunnion supports 39 on the frame 26. The latch member 37 is operated by either of two electromagnets 40 and 41 having movable core members 40 and 41, respectively. The inactive positions of the core members 40 and 41 may be adjusted by means of thumb screws 42 placed below the respective electromagnets.

We provide an auxiliary circuit controlling device having a pivotally mounted knife blade member 43 which is pivotally attached to one end of a link 44, the other end of which is pivotally connected to the link 32. Two contact members 45 and 46 are alternately engaged by the knife blade member hereinbefore mentioned, and they are electrically connected to an indicating means (not shown) for indicating the open and closed positions of the circuit breaker.

The shaft 18 is supported by a plurality of bearings 47 and it extends across the front portion of each single-pole circuit breaker, for the purpose of transmitting the movement of the movable core member 29 of the electromagnct 27 to each of the breakers.

The accelerating and retarding device 5 comprises a cylindrical structure 48 mounted on a frame 49 and adapted to receive a powerful helical accelerating spring 50 which acts against one end of the cylindrical structure 48 and against a tightly fitting piston 51 to retard the action of the spring toward the end of its expansion by a dashpot action. The piston 51 is attached, by any well known means, to a piston rod 52 having a hook on its lower end which operatively engages a pin 53 that projects from one of the several crank arms 17.

The accelerating and retarding dev ce 5 and the main operating device 4 may be located in any desired positions with respect to the individual single-pole circuit breakers.

Assuming the contact members to be in the positions shown in Figs. 1 and 2 and that an overload or a short circuit occurs upon the circuit which the circuit breaker is protecting, the operation will be as follows:

An increased current will traverse the windings of the electromagnets 40 and 41' that are connected in open delta relation to a three phase circuit (not shown) and cause them to draw the movable core members 40- and 41 upwardly to operate the latch member 37 which is restrained from operating otherwise by the force of ravity and a spring 54. The latch 37 re eases the link member 32, which normally cooperates with a guide link 34 to prevent upward movement of the link 30. The link member 32 moves outwardly and upwardly by reason of the forces transmitted to the same from the accelerating spring 50, acting through the shaft 18 and the crank 31. Rotative move ment of the shaft 18 operates the crank arms 17 which transmit their motion, through the links 17", the bell crank levers 19, the links 21 and the levers 22 to the rods 12 to effect disengagement of the movable contact members 9 and 10 from the stationary contact members 7 with great rapidity. Near the end of the movement of the contact members 9 and 10, the shock resulting from the rapidly accelerated motion is absorbed by the piston 51 by reason of its action against the air being compressed in the lower part of the cylindrical structure 48. When the link 32 moves upwardly, the knife blade member 43 engages the contact member 45 to complete a circuit through an indicating device (not shown) to indicate that the breaker is in its open position.

The operation of closing the breaker is similar to that above described in that, current traverses the winding 28 of the electromagnet 27, thereby attracting the movable core member 29 with such force as to move it downwardly andti'ansmit its motion through the link 39 and the crank arm 31 to the shaft 18. The rotative movement of the shaft 18 causes the crank arms 17 to move downwardly, and they transmit their downward motion, through the links 17 the bell crank levers 19 the links 21 and thecurved pivotally mounted levers 22, to the links 25. which move upwardly and carry the rods 12 and the movable contact members 9 and 10 to effect their engagement with the stationary contact members 7. The rotative movement of the shaft also causes the pin 53 to move downwardly to compress the spring 50. The core member 29 will be retarded toward the end of its downward movement by compressing the air in the closed structure constituting the stationary core member of the electromagnet 27.

lVhen the link 30 moves downwardly, the 1115 link 32 that, is pivotally associated with the same moves inwardly and downwardly to engage the latch 37 and to act as a restraining toggle joint to prevent disengagement of the contact members until the latch mem- 120 ber 37 is again tripped to release the operat ing mechanism. VVhen the link 32 moves downwardly, it effects an engagement between the knife blade member 42- and the stationary contact member 46 to complete 125 an auxiliary circuit for indicating the closing of the breaker, as hereinbefore described.

Since various structural modifications may be efiected within the scope of our invention, we desire that only such limitations 180 shall be imposed as are set forth in the appended claims.

We claim as our invention:

1. An operating mechanism for a circuit interrupter comprising a base member, an operating electromagnet, an operating shaft having a crank arm thereon, a link for opcratively connecting e electromagnet to the crank arm, a lever arm operatively connected to the crank arm, a latch for the lever arm and means for so guiding the lever arm that it moves downwardly away from the base member and then toward the base member when the electromagnet is actuated.

2. An operating mechanism for a circuit interrupter comprising a base member, an operating means, an operating shaft having a crank arm thereon, a lever arm connected to the crank arm, means for connecting the operating means to the crank arm, a latch member and means for so guiding the lever arm that it moves do nwardly away from the base member and vhen toward the base member when the operating means is actuated.

3. An operating mechanism for a circuit interrupter comprising a base member, an operating electromagnet, a rotatable shaft having a crank arm thereon, a link for 0peratively connecting the movable member of the electromagnet to the crank arm, a latch member, a latch arm connected to the crank arm and adapted to cooperate with the latch member, and means for so guiding the latch arm that it moves downwardly away from the base member and then toward the base member when the electromagnet is energized. 4. An operating mechanlsm for a 01mm interrupter comprising a base member, an

operating electromagnet, a rotatable shaft operatively connected to the electromagnet, a lever arm operatively connected to the shaft, a latch for engaging one end of the lever arm, and a link member for so guiding the lever arm that it moves downwardly away from the base member and then toward the base member when the electromagnet is energized. J

5. An operating mechanism for a circuit interrupter comprising a base member, an operating electromagnet mounted at the lower end thereof, a rotatable shaft operatively connected to the electromagnet, a lever arm connected to the shaft, a latch member for the lever arm, and means for so guiding the lever arm that it moves away from the base member, toward the base member and toward the electromagnet when the electromagnet is energized.

6. An operating mechanism for a circuit interrupter comprising a base member, an operating electromagnet, an operating shaft having a crank arm thereon, a link for connecting the electromagnet to the crank arm, a lever arm connected to the crank arm, and means connected between the base member and the lever arm for so guiding the lever arm that it moves downwardly toward the electromagnet and away from the base member and then toward the base member when the electromagnet is actuated.

In testimony whereof, we have hereunto subscribed our names this 24th day of Nov.,

JOSEPH N. MAHONEY. HOWARD G. MAoDONALD. Witnesses JOHN MoKEoHNIn, B. B. HrNEs.

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