US3340375A

US3340375A - Electric circuit breaker with auxiliary switch means

Info

Publication number: US3340375A
Application number: US493834A
Authority: US
Inventors: George W Kiesel; Henry E S Owen
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1965-10-07
Filing date: 1965-10-07
Publication date: 1967-09-05
Anticipated expiration: 1984-09-05

Description

Sept. 5, 1967 K|ESEL ET AL 3,340,375

ELECTRIC CIRCUIT BREAKER WITH AUXILIARY SWITCH MEANS Filed Oct. "7, 1965 INSULATION INVENTORS GEbRGE W. X15551. HENRY E. S. OWE/V A TTURNEY United States Patent 3,340,375 ELECTRIC CIRCUIT BREAKER WITH AUXILIARY SWITCH MEANS George W. Kiesel and Henry E. S. Owen, Unionville, Conn., assignors to General Electric Company, a corporation of New York Filed Oct. 7, 1965, Ser. No. 493,834 3 Claims. (Cl. 200153) ABSTRACT OF THE DISCLOSURE An electric circuit breaker assembly including a main housing containing a pair of separable contacts and a movable member that moves with the contacts between open and closed circuit positions; an auxiliary switch is included within the main housing and includes its own insulating casing and its own operating member movable between on and olf position and biasing means biasing the operating member to a first one of these positions at all times; a pivoted actuating member is mounted fixedly With respect to the auxiliary switch housing, and second biasing means is provided acting on the actuating member and biasing it to a position in which it engages the operating member of the auxiliary switch and retains it in the position opposite to the aforesaid first position; the aforesaid movable member which moves with the separable contacts of the circuit breaker engages the actuating member and moves it away from its normal position against the bias of the second biasing means, thereby permitting the first biasing means to move the operating member of the auxiliary switch to the said first position; the actuating member is free to move a substantial distance against the second biasing means beyond the point where the operating member of the auxiliary switch has been moved to its first position, thereby permitting a greater latitude of movement by the movable member of the circuit breaker mechanism.

The present invention relates to electrical circuit breakers and more particularly to circuit breakers including auxiliary switch members for operating auxiliary devices to provide remote indication or control in accordance with the condition of the circuit breaker mechanism.

Generally, auxiliary switches desirably are incorporated within the circuit breaker casing for actuation upon movement of the circuit breaker mechanism to the open circuit (off) condition, or to the closed circuit (on condition, depending upon the construction of the switch, and thereby to control a remote device or indicator. Auxiliary switches may be used to operate trip or bell alarms, which are special type auxiliary switches incorporated within the circuit breaker casing and actuated upon movement of the circuit breaker mechanism to the tripped or automatically open position, such as in response to an overload or short circuit condition in the circuit controlled by the circuit breaker. Auxiliary switches may be used to operate accessory devices such as trip or bell alarms, indicating lights, relays, contactors, and other similar uses simultaneously with the operation of the breaker. These switches may also be used as electrical interlocks to actuate an emergency power supply. Auxiliary switches may be used in connection with other auxiliary devices commonly used .in association with circuit breakers, such as undervoltage trip devices and remote trip devices.

Electric circuit breakers of the type referred to herein generally include an insulated casing of molded synthetic plastic material, and are usually provided in two and three-pole forms. However the auxiliary switch of this invention may be used with a single pole circuit breaker as well. The insulating casing provides elongated, substantially isolated chambers corresponding in number to the number of poles. Thus a two-pole breaker comprises an insulated casing having two side-by-side elongated chambers and a three-pole breaker comprises an insulating casing having three side-by-side elongated chambers.

In the construction of such circuit breakers, it is conventional practice to provide in each of such chambers at least one relatively stationary contact and one relatively movable contact carried by a pivotally supported contact arm. In addition, in one of such chambers, the major portion of an operating mechanism is disposed and arranged to operate all of such contact arms between open and closed circuit positions either (a) manually by means of an operating handle, or (b) automatically by means of a releasable member normally held by a latch member which in turn is releasably held by a trip" device actuated in response to abnormal electrical conditions in the circuit control led by the circuit breaker to release the latch member. The contact arms of each of theseveral chambers are included in the operating mechanism of the circuit breaker.

Because of the presence of the major portion of the opera-ting mechanism in one pole chamber of the circuit breaker in addition to to the contacts and contact arm, the room available therein for auxiliary switches or other devices is extremely limited. Therefore, auxiliary devices such as auxiliary switches, trip alarms, undervoltage trip devices, and remote trip devices have, because of their size and construction, necessarily been located only in the pole chambers of such breakers other than that occupied by the major portion of the operating mechanism. The number and combination of such auxiliary devices which can be used in such breakers according to conventional practice is extremely limited. For example, if it is desired to utilize an auxiliary switch and a trip alarm device in a three-pole breaker, both chambers not occupied by the operating mechanism would have to be utilized. This renders it very ditficult to provide in the same breaker, an undervoltage trip device or remote trip device without increasing the size or other major reconstruction. Similarly, when any one of the above-mentioned auxiliary devices is incorporated in a two-pole circuit breaker in accordance with conventional practice, the one available pole chamber must be utilized and no other auxiliary device can be provided conveniently within the same circuit breaker.

It is an object of this invention to provide a novel auxiliary switch for use in association with an electrical circuit breaker which is extremely compact. and efiective.

It is also an object of this invention to provide such a novel auxiliary switch which comprises a plurality of switches for operating accessories such as indicating lights, relays and the like to indicate the condition of the circuit breaker.

Another object is to provide such an auxiliary switch in the form of a trip alarm which can be mounted in the same pole chamber as that occupied by the main operating mechanism of the circuit breaker.

A further object is to provide such as auxiliary switch which enables actuation of relatively delicate switch components by the relatively powerful operating mechanism of the circuit breaker while substantially avoiding injury thereto.

It has now been found that the foregoing objects and other advantages can be readily attained in an auxiliary switch for use with an electrical circuit breaker comprises a support member for mounting on an associated circuit breaker and a switch member for mounting on the support member for operating an accessory device by movement of an element therein between open and closed position. An operating member is movably mounted on the switch member for positioning the switch member in open and closed circuit positions. An actuating member is pivotably mounted on the support member and engages the operating member upon pivoting thereof to move the operating member and actuate the switch member from one circuit position to the other circuit position. The actuating member has means engageable by the operating mechanism of the associated circuit breaker for pivotal movement thereof away from the operating member. A spring means is operable between the support member and the actuating member and normally biases the actuating member about the pivotal mounting in the direction of the operating member.

In accordance with one embodiment of this invention, the auxiliary switch is a trip alarm supported in the same pole section as the main circuit breaker operating mechanism, and the pivotable actuating member includes a part projecting into the path of the releasable or tripping member of the circuit breaker mechanism so as to be operated upon tripping of the circuit breaker.

The auxiliary switches may include one to four or more normally open or normally closed switches. A normally open switch is off when the circuit breaker is in the open or tripped condition, and closed when the circuit breaker is in the closed condition. A normally closed switch is closed when the circuit breaker is in the open or tripped condition and open when the circuit breaker is closed. A single auxiliary switch may be constructed to operate either as a normally open or a normally closed switch depending upon the leads from the switch that are used. Thus, an auxiliary switch may be selected that will either open a pair of contacts to deenergize a circuit when engaged by the actuating member or close a pair of contacts and energize a circuit when engaged by the actuating member. Accordingly, various auxiliary switches may be selected and used in combination according to the purpose of the auxiliary device to which they are individually connected and whether it is desired to have the device energized or deenergized upon the opening or tripping of the circuit breaker mechanism.

In accordance with the present invention, the auxiliary switch provides an actuating member which enables the operation of relatively delicate switch components in the switch member by the relatively hard driving operating mechanism of the circuit breaker without substantial likelihood of injury thereto.

The invention will be more fully understood from the following detailed description and the scope will be pointed out in the appended claims.

In the drawings:

FIGURE 1 is a side elevational view of an electrical circuit breaker assembly incorporating the present invention with a portion of the side wall of the insulating casing thereof being broken away for clarity of illustration and showing the circuit breaker operating elements in the on condition;

FIGURE 2 is a side elevational view to an enlarged scale of the internal elements of the circuit breaker assembly of FIGURE 1 showing the circuit breaker operating elements in the off position and parts of the auxiliary switch in phantom line;

FIGURE 3 is a side elevational view to an enlarged scale of a portion of the circuit breaker of FIGURE 1 with the operating parts of the auxiliary switch being shown in phantom line; and

FIGURE 4 is a front elevational view to an enlarged scale of the auxiliary switch of FIGURE 1 with portions thereof in section.

Referring now in detail to the drawings, the invention is shown in assembly with an electrical circuit breaker designated by the numeral 10 which has a generally rectangular insulating casing with a base portion 12 and a removable cover portion 14. For convenience, the construction of a single pole chamber of the circuit breaker 10 is shown and will be described in detail although it will be understood, however, that the circuit breaker 10 generally includes three or more pole chambers, all substantially identical except that the center pole chamber contains the major portion of the operating mechanism. Each pole chamber includes a relatively stationary contact (not shown) and a relatively movable contact (not shown), carried by a contact arm 16 pivotably supported by a shaft 18 which is mounted on the base 12. The contact arm 16 is limited in movement about the shaft 18 by a stop 19 mounted on the base 12.

In accordance with conventional construction, the movable contacts (not shown) are electrically connected to a trip unit 20 which is in turn electrically connected to a load terminal (not shown) and the stationary contacts are electrically connected to a line terminal (not shown). The electric circuit through each pole may therefore be traced as follows: from the line terminal to the stationary contact, and, when the circuit breaker is in the closed position, through the relatively movable contact to the trip unit, and then finally to the load terminal.

For the purpose of operating the contact arm 16 and its movable contact to open and closed circuit position, a suitable operating mechanism (only partially shown) is provided and has pivotably mounted operating handle 22 projecting the top wall of the circuit breaker cover 14. Three movable contact arms 16 of the three-pole section are ganged together for movement by the operating mechanism as a unit by means of the cross-bar 24 which is rigidly attached to each of the arms 16. The operating mechanism may, for example, be as shown in United States Patent No. 2,921,169 issued Jan. 12, 1960, to E. B. Judd and J. D. Young, and assigned to the same assignee as the present invention.

For the purpose of providing a plurality of auxiliary switching means, which shall be in one condition when the circuit breaker is in the off position and another condition when the circuit breaker is in the on position, the circuit breaker assembly incorporates an auxiliary switch including a sheet metal support bracket or member generally designated by the numeral 26 with a generally flat, plate-like body portion 28 and a bent-over flat end portion 30 which abuts against the trip unit 20 and is secured thereto by means of bolts 32 disposed in apertures 33. On the opposite end of the body portion 28, another bent-over flat portion 34 is engaged by rivets 38 with an insulating support 37 which is keyed into and supported by slots (not shown) in the base 12 of the circuit breaker 10. A depending flange portion 44 on the body portion 28 pivotally supports a generally L-shaped switch actuating member generally designated by the numeral 46 by means of the pivot pin 48 which is disposed in an aperture (not shown) in the central portion of the actuating member 46. The L-shaped actuating member 46 has two

leg portions

47 and 49 which extend to opposite sides of the pivot pin 48. A helical tension spring 50 is hooked in the aperture 52 in the leg portion 47 of actuating member 46 and in the aperture 54 in the body portion 28 of the support bracket 26. A bent-over flange portion 56 on the leg portion 49 provides a surface area for engagement with the cross-bar 24 of the contact arm 16.

A plurality of miniature push-button actuated switch FIGURE 4. Each of the miniature switch members 60 are connected together and attached to the bracket sup port 26 by means of bolts 62. The switch members 60 are each separated by insulating members 63 as best seen in FIGURE 4. Each of the miniature switch members 60 comprises an insulating casing 64, a stationary contact 66 mounted On a conducting support member 68 mounted On the insulating casing 64, and a movable contact memher or switch element 70 movably supported in the casing 64 by means of a resiliently deflectable connecting support member 72 which acts as a leaf spring biasing the movable contact 70 into engagement with the stationary contact 66. The resiliently deflectable support member 72 is adapted to be operated by a rectilinearly moving pushbutton operating member 74 which is slidably seated in the casing 64 and projects outwardly thereof. The construction and arrangement of the miniature switch members 60 are such that, in the absence of any actuating force on the operating member 74, the resiliently deflectable support member 72 biases the movable contact 70 into engagement with the stationary contact 66. However, it will be obvious that the resiliently deflectable support member 72 may be arranged so that it normally biases the movable contact 70 away from the stationary contact 66 so that the

contacts

66 and 70 are only engaged when the operating member 74 moves the support member 72 toward the stationary contact 66.

An elongated switch operating arm 76 is supported on the flange 78 of the leg portion 47 of the actuating member 46 adjacent the tension spring 50 which biases the actuating member 46 about the pivot pin 48 in the direction of engagement with the operating members 74. The operating arm 76 extends along the bottom portion of switch members 60 so that it may substantially simultaneously engage all the operating members 74.

As shown in FIGURE 1, when the contact arm 16 and operating mechanism of the circuit breaker are moved to the on position, the cross arm 24 is moved from engagement with flange portion 56 of the actuating member 46. In this condition, the actuating member 46 is biased about the pivot pin 48 by the spring 50 into engagement with the operating members 74, whereby the operating members 74 are slidably moved to the position illustrated in FIGURE 3. When the actuating member 46 is in the on position, the operating member 74 is biased against the resiliently deflectable support member 72 so that the movable contact 70 is disengaged from the stationary contact 66. Accordingly, the switch 60 is in the open circuit position when the contact arm 16 and the operating mechanism of the circuit breaker are in the closed circuit position.

When the operating mechanism of the circuit breaker is moved to the open position as illustrated in FIGURE 2, the contact arm 16 is pivoted in a counterclockwise direction about the shaft 18 until it is restrained from upward movement by the stop 19. The cross arm 24 is thus moved into engagement with the flange 56 to rotate the actuating member 46 in a clockwise direction against the force of the tension spring 50, and the switch operating arm 76 of the actuating member 46 is thus moved from engagement with the operating member 74. The resiliently deflectable support member 72 biases the operating member 74 to the position shown in FIGURE 2 and the movable contact 70 is moved into electrical engagement with the stationary contact 66. Accordingly, the auxiliary switch 60 is in the closed circuit position when the contact arm 16 and the operating mechanism of the circuit breaker are in the off or open circuit position. An auxiliary device electrically connected through the auxiliary-switch 60 is thus activated when the stationary contact 66 and movable contact 70 are electrically engaged when the circuit breaker is in the off position. Thus, a relatively fragile auxiliary switch 60 is operable by the actuating member 46 without being in direct contact with the cross-bar 24 of the relatively powerfully driven operating mechanism of the circuit breaker and the relatively large movements thereof. Also by providing the spring biased actuating member 46, the operating member 74 which requires relatively small movements to activate switch 60, may be operated by the relatively large movements of the circuit breaker operating mechanism without damaging the relatively delicate auxiliary switch 60.

As previously indicated, the resiliently deflectable support member 72 may be arranged so that it biases the movable contact 70 away from engagement with the stationary contact 66 when the actuating member 46 is in the off position shown in FIGURE 2. In such an arrangement, the auxiliary switch may be easily arranged so that the operating member 74 biases the resiliently deflectable support member 72 into engagement with the stationary contact 66 when the actuator 46 is in the on position as shown in FIGURE 3, thus activating an auxiliary device when the circuit breaker is in the on condition.

It can be seen from the foregoing detailed description and drawings that the present invention provides an auxili-ary switch for use with a circuit breaker which is novel, effective and compact, and which may be used in combination for operating a plurality of accessory devices such as to indicate the condition of the circuit breaker. The auxiliary switches may be selected so that they either open or close a circuit upon tripping or manually opening the circuit breaker, or to operate a trip alarm. The switches are sufliciently compact to be mounted in the same pole chamber as that of the operating mechanism of the circuit breaker and also provide for actuating relatively delicate switch components upon tripping or opening of the relatively powerful circuit breaker mechanism without damage thereto.

While we have disclosed only certain embodiments of the invention, it will be readily appreciated that many modifications thereof may be made. We therefore intend by the appended claims to cover all such modifications as fall within the true spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An electric circuit breaker assembly comprising:

(a) an insulating casing;

(b) at least one pair of relatively separable contacts supported in said casing;

(c) operating mechanism in said insulating casing for moving said contacts between open and closed circuit positions;

(d) a movable member movably supported in said insulating casing, said movable member moving between first and second positions upon movement of said contacts between said open and closed circuit positions respectively;

(e) an auxiliary switch supported in said insulating casing, said auxiliary switch comprising an insulating housing and an operating member carried by said insulating housing and movable between first and second positions to operate said switch between open and closed circuit conditions;

(f) first biasing means biasing said operating member for movement toward said firstposition at all times;

(g) an actuating member pivotally supported on said insulating housing of said auxiliary switch member and movable between first and second positions, said actuating member when in said first position engaging and retaining said operating member in said second position against the bias of said first biasing means;

(h) second biasing means biasing said actuating member toward said first position at all times, said second biasing means exceeding said first biasing means whereby said actuating member normally engages said operating member and retains said operating member in said second position;

(i) said movable member engaging said actuating member when said contacts are in said open circuit position and moving said actuating member from said first toward said second position against the bias of said second biasing means whereby said first biasing means is free to move said auxiliary switch oper ating member to said first position.

2. An electirc circuit breaker assembly as set forth in 75 claim 1 wherein said actuating member travels a sub- 7 stantial distance in the direction from said first toward said second position after said operating mechanism is in said second position whereby travel of said movable member is substantially uninhibited by said actuating member.

3. An electric circuit interrupter assembly as set forth in claim 2 wherein said circuit breaker assembly includes at least one pivotally mounted contact arm assembly and wherein said movable member comprises a portion of said pivotally mounted contact arm assembly.

8 References Cited UNITED STATES PATENTS 7/1954 Boller et a1 200-167 4/1961 Piteo et al. 200-414 ROBERT S. MACON, Primary Examiner. ROBERT K. SCHAEFER, Examiner. H. BURKS, Assistant Examiner.

Claims

1. AN ELECTRIC CIRCUIT BREAKER ASSEMBLY COMPRISING: (A) AN INSULATING CASING; (B) AT LEAST ONE PAIR OF RELATIVELY SEPARABLE CONTACTS SUPPORTED IN SAID CASING; (C) OPERATING MECHANISM IN SAID INSULATING CASING FOR MOVING SAID CONTACTS BETWEEN OPEN AND CLOSED CIRCUIT POSITIONS; (D) A MOVABLE MEMBER MOVABLY SUPPORTED IN SAID INSULATING CASING, SAID MOVABLE MEMBER MOVING BETWEEN FIRST AND SECOND POSITIONS UPON MOVEMENT OF SAID CONTACTS BETWEEN SAID OPEN AND CLOSED CIRCUIT POSITIONS RESPECTIVELY; (E) IN AUXILIARY SWITCH SUPPORTED IN SAID INSULATING CASING, SAID AUXILIARY SWITCH COMPRISING AN INSULATING HOUSING AND AN OPERATING MEMBER CARRIED BY SAID INSULATING HOUSING AND MOVABLE BETWEEN FIRST AND SECOND POSITIONS TO OPERATE SAID SWITCH BETWEEN OPEN AND CLOSED CIRCUIT CONDITIONS; (F) FIRST BIASING MEANS BIASING SAID OPERATING MEMBER FOR MOVEMENT TOWARD SAID FIRST POSITION AT ALL TIMES; (G) AN ACTUATING MEMBER PIVOTALLY SUPPORTED ON SAID INSULATING HOUSING OF SAID AUXILIARY SWITCH MEMBER