US3009039A

US3009039A - Removable cover for current limiting fuse housing

Info

Publication number: US3009039A
Application number: US814214A
Authority: US
Inventors: Jr William M Scott
Original assignee: ITE Circuit Breaker Co
Current assignee: ITE Circuit Breaker Co
Priority date: 1959-05-19
Filing date: 1959-05-19
Publication date: 1961-11-14
Anticipated expiration: 1978-11-14

Description

Nov. 14, 1961 w. M. SCOTT, JR 3,009,039

REMOVABLE COVER FOR CURRENT LIMITING FUSE HOUSING Filed May 19, 1959 2 Sheets-Sheet 1 Ia? 5; E z 5- 5.

5"" f7 INVENTOR.

Mil/AM M..Sc07'7; J42.

Nov. 14, 1961 w. M. SCOTT, JR 3,009,039

REMOVABLE COVER FOR CURRENT LIMITING FUSE HOUSING Filed May 19, 1959 2 Sheets-Sheet 2 Z 58 W 2 J7 J2 f m 76 -w 7:

Z I G 4- J8 J7 62 J6 United States Patent O 3, 0 REMOVABLE COVER FOR CURRENT LIMITING FUSE HOUSING William M. Scott, Jr., Bryn Mawr, Pa., assignor to I-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Filed May 19, 1959, Ser. No. 814,214 7 Claims. (Cl. 200-133) My invention relates to a means for locking and removing a current limiting fuse housing from its associated breaker where considerable force is required to separate the disconnect contacts connecting the two units.

Current limiting fuse housings associated with circuit breakers Where the current limiting fuses are electrically and mechanically coordinated with the circuit breakers are set forth in copending application Serial No. 622,042, filed November 14, 1956, now Patent No. 2,924,688, entitled End Mounting of a Current Limiting Device Associated With a Circuit Breaker, in the name of William Harold Edmunds and assigned to the assignee of the present invention.

Since there must be high pressure contact engagement between the disconnects which electrically connect the current limiting fuses positioned within a housing and the circuit breaker disconnects, a large mechanical force is required to remove the fuse housing from. the circuit breaker.

In the past, the operator could grip only the relatively smooth sides of the fuse housing, or a relatively short protruding lip of the fuse housing when removing the fuse housing.

In accordance with my invention, I provide a bale or wire means which is connected to a plate fastened to the fuse housing. A rigid connecting means extending from the base extension of the circuit breaker which receives the fuse housing is then taken through a key-type opening in the plate so that the plate and thus the housing is locked or unlocked to the circuit breaker depending on the position of the key-type opening. When the plate is in a looked position, the fuse housing is rigidly secured to the circuit breaker base. Movement of the plate in this position is normally prevented by a bale which is pivotally mounted to the plate and can interfere with movement of the plate. When the fuse housing is to be removed, the bale is lifted from its interfering position to permit the plate to be moved from a locked position to an unlocked position by movement of the keyed connection between the circuit breaker base and the fuse housing. However, the plate is still attached to the fuse housing and may be pulled upwardly by means of the bale which previously operated as an interfering means, so that the bale plate and fuse housing are lifted as a unit. The bale, therefore, serves the dual function of being a handle for removing the fuse housing from the circuit breaker, as well as means for rigidly holding the plate and thus, the fuse housing, locked to the circuit breaker base.

Accordingly, a primary object of my invention is to provide a novel manner for locking and removing a fuse housing from a circuit breaker.

Another object of my invention is to provide a novel grasping means for easily removing a fuse housing from a circuit breaker wherein the grasping means further operates as a looking means to rigidly secure the fuse housing and the circuit breaker.

Another object of the invention is to provide a simple means for looking a fuse housing to a circuit breaker housing.

A further object of the invention is to provide an ef- 3,009,039 Patented Nov. 14, 1961 fective means for removing a fuse housing from a circuit breaker housing.

Another object of my invention is to removably secure a plate to a current limiting fuse housing, and pro. vide a key slot in the plate which cooperates with fastening means extending from the circuit breaker base whereby the fuse housing is rigidly locked by a bale fastened to the plate when the plate is in a first key position, and is capable of being removed by the bale when the bale is moved from its locking position and the plate is in a second key position. 7

These and other objects of my invention will become apparent from the following description when taken in connection with the drawings, in which:

FIGURE 1 is an exploded perspective view ofa cir-' cuit breaker housing having a removably connected fuse housing wherein the fuse housing is modified in accord ance with the present invention.

FIGURE 2 is a cross-sectional detail view of the manner in which the plate of FIGURE 1 is movably secured with respect to the fuse housing.

FIGURE 3 is a top view of the fuse housing of FIG URE 1 with the bale and plate in the locked positions.

FIGURE 4 is a top view similar to FIGURE 3 wherein the bale has been lifted from its interfering position, and the plate moved to an unlocked position so that the bale may be used to pull the fuse housing out of engagement with the circuit breaker housing.

Referring now to FIGURE 1, the figure shows a structure which, for the exception of the fuse housing cover structure, is fully described in the above noted copending application Serial No. 622,042.

In FIGURE 1, a circuit breaker housing 20 is provided with an extending base portion 21 which may be either an integral part of the circuit breaker 20 or may be a removable base portion. An operating mechanism of any desired type is contained within circuit breaker housing 20, such as the mechanism shown in US. Patent No. 2,574,093 to William Harold Edmunds. Operating handle 30 operates a pair of contacts for each phase (not shown) of the three-phase circuit breaker illustrated in FIGURE 1. Contacts of each of the circuit breaker phases are terminated by disconnect contacts 31, 32 and a contact 33 which is not seen in FIGURE 1.

The extension 21 of FIGURE 1 carries additional

disconnect contacts

34, 35 and 36 which cooperate with contacts 3-1, 3-2 and 33 respectively for connecting a current limiting fuse in series with each of the respective circuit breaker phases. Each of disconnect contacts 31 through 36 are of the tulip-clip type, described in copending application Serial No. 536,586, filed September 26, 1955, and assigned to the assignee of the present invention, and receive a stud means in electrical and mechanical engagement. However, for purposes of the present invention, disconnect contacts 31 through 36 could be of any desired type.

Fuses, such as fuse 40 of FIGURE 1, are provided for each phase of circuit breaker 20, and have disconnect studs, such as disconnect studs 41. through 45 whe'r'es'tuds 4-1, 42 are associated with fuse 40';

studs

43 and 44 are associated with a fuse of the middle phase, and stud 45 and a stud not shown are associated with the fuse of the third phase. Studs 41 and 42; cooperate with disconnects 36 and the disconnect at location 33 in FIGURE 1, while disconnects 43 and 44 cooperate with disconnects 35 and 32 respectively, and disconnect 45' and a second disconnect of the third fuse (not shown) cooperate with disconnects 34 and 31 respectively.

Because the connection between the current limiting fuse studs and their cooperating tulip-clip connectors must be a low resistance connection to avoid the generation of excess heat, a substantial mechanical force is provided for this connection. This, however, makes it very diificult to pull the fuse housing away from the circuit breaker housing.

In the present invention, I have solved this problem by providing a bale means 50, seen in FIGURES 1, 3 and 4, which is pivotally connected to

ears

52 and 54 of plate 56. Plate 56 is movably secured to the top 57 of housing 37 by bolt means 58 and 60 which extend through

elongated openings

62 and 64 respectively of plate 56, and are secured beneath the top of housing 37.

A cross-sectional view of this securing structure is shown in FIGURE 2 for bolt 58. Bolt 58 has a head larger than the width of slot 62 in plate 56, and is secured beneath the top of cover 37 by a lock nut 66. However, the connection is such that there can still be relative longitudinal motion between plate 56 and top 57 of housing 37.

In order to rigidly secure fuse housing 37 to the extended base 21 of the circuit breaker housing 20, the plate 56 is provided with the two

key slots

68 and 70. These key slots cooperate with bolts 72 and 74 of FIG- URE 1, which have enlarged

heads

76 and 78 respectively which can pass through

openings

80 and 82 in the top of housing 37, as seen in FIGURE 1, and the enlarged portion of

key slots

68 and 70.

Accordingly, when the fuse housing 37 is locked to extended base 21, the plate 56 will be in the position of FIGURE 3 where the enlarged

heads

76 and 78 of bolts 72 and 74 lie over the reduced width portion of key slots 68 and 7 0. When the fuse housing 37 is to be unlocked from extended base 21, the plate 56 is moved from the position of FIGURE 3 to the right and to the position of FIGURE 4 whereupon enlarged

heads

76 and 78 of bolts 72 and 74 move into the enlarged key slot portion. The housing may now be lifted upwardly with the

bolt heads

76 and 78 clearing the larger diameter openings to disconnect fuse housing 37 from housing 20.

As previously set forth, a substantial amount of force is required to physically disconnected housing 37. In the present invention, however, the bale 50 may be pivoted upwardly to an operating position, as shown in FIGURE 4, so that bale 50, which may be conveniently grasped,

can be pulled upwardly to exert a force on the fuse housing 37 through the plate 56 and securing

bolts

58 and 60 which secure the plate to the housing 37.

-I have further found that the lifting function of bale 50 can be coordinated with the locking and unlocking function of plate 56 in a novel manner whereby bale 50 may interfere with the movement of plate 56 so that the plate 56 can be secured in the locked position. More specifically, the upper surface 57 of housing 37 is provided with a pair of

protrusions

84 and 86, and a further protrusion 88. As shown in FIGURES l, 3 and 4, the

protrusions

84 and 86 are spaced to receive a portion of bale 50 between them, while protrusion 88 is positioned adjacent the other side of bale 50 when the bale is in a flat and interfering position.

The upper surface 57 is further provided with a protrudingpin 90 having a necked-down portion 92 at an intermediate portion thereof. The necked-down portion 92 of pin 90 cooperates with an indentation 94 in bale 50 so that the necked-down portion 92 can lock bale 50 in the interfering position when receiving indentation 94. When the bale is in the position of FIGURE 3, it will be readily apparent that the plate 56 cannot be moved to the right and to the position of FIGURE 4, since this motion is prevented by

protrusions

84, 86 and 88. Accordingly, the plate 56 is secured in its locking position and the fuse housing 37 is locked to the circuit breaker housing.

When the bale 50 is pressed at its center to remove indentation 94 from necked-down portion 92 of pin 90, the bale may be rotated upwardly from an interfering position to the operating position of FIGURES 1 and 4, and

at this point the plate 56 may be moved to the right. Thereafter, the bale may be readily used to remove the fuse housing from the circuit breaker housing in the manner previously described.

If desired, the plate 56 can be interlocked with the circuit breaker trip mechanism so that movement of plate 56 to the unlocked position will trip the circuit breaker. This structure is schematically shown in FIGURE 1 by the dotted line from plate 56 to circuit breaker 20 and prevents the removal of the fuse housing while the circuit breaker is closed and current flows through the disconnect contacts.

Although I have described preferred embodiments of my novel invention, many variations and modifications will now be obvious to those skilled in the art, and I prefer therefore to be limited not by the specific disclosure herein but only by the appended claims.

I claim:

1. In a circuit interrupter; said circuit interrupter comprising a first housing containing a current limiting fuse and a second housing containing a circuit breaker; said current limiting fuse having disconnect contact means; said circuit breaker having disconnected contact means; said current limiting fuse disconnect contact means being connectible to said circuit breaker disconnect contact means; means for removing said first housing and said current limiting fuse from said second housing and said circuit breaker when said disconnect contact means are connected; said removing means comprising a bale; said bale being pivotally operatively connectetd to the top of said first housing; a plate means; said bale being carried by said plate means; said plate means being movably secured to the top of said first housing and being movable in a plane parallel to the top of said first housing between a locked position and an unlocked position with respect to said second housing.

2. In a circuit interrupter; said circuit interrupter comprising a first housing containing a current limiting fuse and a second housing containing a circuit breaker; said current limiting fuse having disconnect contact means; said circuit breaker having disconnect contact means; said current limiting fuse disconnect contact means being connectible to said circuit breaker disconnect contact means; means for removing said first housing and said current limiting fuse from said second housing and said circuit breaker when said disconnect contact means are connected; said removing means comprising a bale; said bale being pivotally operatively connected to the top of said first housing; a plate means; said bale being carried by said plate means; said plate means being movably secured to the top of said first housing and being movable between a locked position and an unlocked position with respect to said second housing; said bale being pivotally movable between an interfering position and an operating position; said bale blocking movement of said plate means to said unlocked position when said bale means is in said interfering position and permitting movement of said plate means to said unlocked position when said bale means is in said operating position.

3. In a circuit interrupter; said circuit interrupter comprising a first housing containing a current limiting fuse and a second housing containing a circuit breaker; said current limiting fuse having disconnect contact means; said circuit breaker having disconnect contact means; said current limiting fuse disconnect contact means being connectible to said circuit breaker disconnect contact means; locking means for locking said first housing to said second housing; said locking means comprising a plate; said plate being movably secured to said first housing; said second housing having an extension means projecting through aperture means in said plate; said plate being movable to a locked position and an unlocked position with respect to said extension means; said plate when in said locked position having a portion thereof disposed within a recess of said extension means.

4. In a circuit interrupter; said circuit interrupter comprising a first housing containing a current limiting fuse and a second housing containing a circuit breaker; said current limiting fuse having disconnect contact means; said circuit breaker having disconnect contact means; said current limiting fuse disconnect contact means being connectible to said circuit breaker disconnect contact means; locking means for locking said first housing to said second housing; said locking means comprising a plate; said plate being movably secured to said first housing; said second housing having an extension means; said plate being movable to a locked position and an unlocked position with respect to said extension means; and a handle means; said handle means being connected to said plate for removing said first housing from said second housing; said handle means being movable from an interfering position to an operating position; said handle means preventing movement of said plate to said unlocked position when said handle means is in said interfering position.

5. In a circuit interrupting means; a first circuit interrupter secured within a first housing and a second circuit interrupter secured within a second housing; said first and second circuit interrupters having cooperating disconnect means for connecting said first and second circuit interrupters; a plate; said plate being movably mounted to the upper surface of said first housing; said plate having a key slot therein; said second housing having a protruding member secured thereto; said protruding member being positioned Within said key slot of said plate; said plate being movable between a locking position with said protruding member in a restricted portion of said key slot and an unlocked position with said protruding member in an enlarged portion of said key slot; said plate and said first housing being removable from said first housing only when said plate is in said unlocked position.

6. In a circuit interrupting means; a first circuit interrupter secured Within a first housing and a second circuit interrupter secured within a second housing; said first and second circuit interrupters having cooperating disconnect means for connecting said first and second circuit interrupters; a plate; said plate being movably mounted to the upper surface of said first housing; said plate having a key slot therein; said second housing having a protruding member secured thereto; said protruding member being positioned within said key slot of said plate; said plate 'being movable between a locking position with said protruding member in a restricted portion of said key slot and an unlocked position with said protruding member in an enlarged portion of said key slot; said plate and said first housing being removable from said first housing only when said plate is in said unlocked position; said plate having a handle secured thereto; said handle being operable to remove said plate and first housing from said second housing when said plate is in said unlocked position.

7. In a circuit interrupting means; a first circuit interrupter secured within a first housing and a second circuit interrupter secured within a second housing; said first and second circuit interrupters having cooperating disconnect means for connecting said first and second circuit interrupters; a plate; said plate being movably mounted to the upper surface of said first housing; said plate having a key slot therein; said second housing having a protruding member secured thereto; said protruding member being positioned Within said key slot of said plate; said plate being movable between a locking position with said protruding member in a restricted portion of said key slot and an unlocked position with said protruding memher in an enlarged portion of said key slot; said plate and said first housing being removable from said first housing only when said plate is in said unlocked position; said plate having a handle secured thereto; said handle being operable to remove said plate and first housing from said second housing when said plate is in said unlocked position; said handle being movable from an interfering position to an operable position; said handle preventing movement of said plate to said unlocked position when said handle is in said interfering position.

References Cited in the file of this patent UNITED STATES PATENTS 1,312,626 Grannis Aug. 12, 1919 2,256,232 Bennet Sept. 16, 1941 2,744,982 Smith May 8, 1956 2,905,791 Edmunds Sept. 22, 1959