US3851284A

US3851284A - Circuit breaker

Info

Publication number: US3851284A
Application number: US00457418A
Authority: US
Inventors: A Yoshino; H Imanishi
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 1973-04-06
Filing date: 1974-04-03
Publication date: 1974-11-26
Anticipated expiration: 1991-11-26
Also published as: FR2224860A1; FR2224860B1; FR224861A; IT1005939B; DE2416153A1; DE2416153B2; GB1462692A

Abstract

A ''''trip'''' indicative circuit breaker having an improved operating mechanism for switching contacts is provided. Respective components of the operating mechanism are all pivoted compactly between two parallel plates, forming a linkage from detected excess-current responsive piece, through engagingdisengaging frame and turning arm engageable at a slidable-pivot end with the frame, to operating plate coupled at rotatable side to intermediate portion of the arm and an external manual handle. The arm is coupled at the other end to carrier member for opening and closing breaker contacts. When the responsive piece is actuated by detected excess-current, the linkage is broken between the frame and the arm to free the carrier member causing the contacts opened and the handle positioned to ''''trip'''' indicative position. The linkage is restored by handle rotation toward OFF position.

Description

United States Patent 1191 Yoshino et a1.

[ CIRCUIT BREAKER [7 5] Inventors: Akira Yoshino; Hitoshi lmanishi,

both of Seto, Japan [73] Assignee: Matsushita Electric Works, Ltd.,

Osaka, Japan [22] Filed: Apr. 3, 1974 [2]] App]. No.: 457,418

[30] Foreign Application Priority Data Apr. 6, I973 Japan 48/39934 Apr. 6, 1973 Japan 48/39935 Apr. 6, 1973 Japan 48/39938 52 US. (:1 335/6, 335/21, 335/190 [51] Int. Cl. H0lh 77/06 [58] Field of Search 335/6, 202, 201, 190,21,

[56] References Cited UNITED STATES PATENTS 3,204,063 8/1965 Nash et al 337/46 3,742.401 6/1973 Strobel 335/21 Primary Examiner-Harold Broome Attorney, Agent, or Firm-Wolfe, Hubbard, Leydig, Voit & Osann, Ltd;

- ABSTRACT A trip indicative circuit breaker having an improved operating mechanism for switching contacts is provided. Respective components of the operating mechanism are all pivoted compactly between two parallel plates, forming a linkage from detected excess-current responsive piece, through engaging-disengaging frame and turning arm engageable at a slidable-pivot end with the frame, to operating plate coupled at rotatable side to intermediate portion of the arm and an external manual handle. The arm is coupled at the other end to carrier member for opening and closing breaker contacts. When the responsive piece is actuated by detected excess-current, the linkage is broken between the frame and the arm to free the carrier member causing the contacts opened and the handle positioned to trip indicative position. The linkage is restored by handle rotation toward OFF position.

5 Claims, 37 Drawing Figures PATENIEL v 3,851,284

' Sam on N15 PATENTEL MWZ 3 851 .2834

saw 01 or 16 PATENTEL NOV 2 6 I974 sum 09 HF 16 Fig.

cmcurr BREAKER This invention relates to circuit breakers and, more particularly, to an operating mechanism for driving a switching contact part in a circuit breaker having a trip indicating function.

In the circuit breaker in which such component part arrangement as, for example, in the embodiment ofthepresent invention is made, in order to effectively use the space within the apparatus or to obtain many merits in the assembling step, an operating mechanism of a thin type having operating mechanism parts incorporated between two plate members combined with each other at a spacing of about 1 cm and arranged in parallel with each other in front of the apparatus and provided with an operating handle operated in the direc- 7 tion parallel with said plate members in front of the plates will be very useful in some case.

However, in the general conventional apparatus of this kind, as the operating handle is pivoted over bearing plates as fitted upright in front of the apparatus and the operating mechanism is assembled as correlated with another operating mechanism not arranged between the bearing plates with saidv operating handle as a center, such requirements as are described above have not been met. The present invention is suggested to improve the above mentioned defects.

A main object of the present invention is to provide a simple operating mechanism which is so thin as to be housed in a chassis.

Another object of the present invention is to provide an operating mechanism unit which can be assembled by only putting in the respective component parts and combining two plate members by calking. I

A further object of the present invention is to provide an operating mechanism wherein a turning arm can be moved by enlarging an operating force for an excess current detecting element.

Other objects and advantages of the present invention will be made clear by the following description of the invention detailed with reference to a preferred embodiment in conjunction with accompanying drawings, in which:

FIG. 1 is an explanatory view showing schematically the arrangement of a circuit breaker of the present invention;

FIG. 2 is an upper surface view of the apparatus of the present invention;

FIG. 3 is a lower surface view ofthe same with a back lid removed;

FIG. 4 is a side view of the same;

FIG. 5 is a view showing the interior with a part of a cover cut off;

FIG. 6 is an upper surface view shown with the cover removed;

FIG. 7 is an upper surface view in FIG. 6 shown with an upper lid removed;

FIG. 8 is a lower surface view in FIG. 3 with a lower lid removed;

FIG. 9 IS a sectioned view shown along an input terminal and output terminal in FIG. 6;

FIGS. 10A through 10C are upper surface view, lower surface view and vertical sectioned view substantially at the centre of a chassis;

FIG. 11 IS a cross sectional view along a carrier of the chassis;

FIG. 12 is a perspective view of an operating part;

FIG. 13A is a perspective view of the operating part as disassembled, and FIG. [33 shows main elements in the operating part;

FIG. 14A is a front view of the operating part as assembled;

FIG. 14B is a rear view of the same;

FIG. 14C is a side view of the same;

FIG. 15 is a perspective view of an electromagnet employed in the device;

FIGS. 16A through 16C show a coil in the above; FIG. 17 is a perspective view of a switching contact unit;

FIG. 18 is a perspective view of a carrier;

FIG. 19 is a perspective view of an armature;

FIG. 20 is an elevation of a handle;

FIGS. 21 and 22 are fragmentary sectioned views for explaining the operating part as fitted;

FIGS. 23A, B and C are views for explaining the operation of the operating part;

FIGS. 24A through 24C are views for explaining the operation of the contact plate;

FIGS. 24A through 24C are fragmentary sectioned views showing operations of contacting plate; and

FIGS. 25A and 25B are explanatory views showing operative relation between certain main elements in the operating part.

FIG. 1 shall be explained in the following.

FIG. 1 shows a unit arrangement ofa circuit breaker of the present invention. In the drawing, INPUT is an input terminal, OUTPUT is an output terminal and these terminals are arranged on both sides of a case A. B is a switching terminal. C is an excess current detecting part. D is an operating part. An upper space and lower space are formed by a partition wall E in the case A. The operating part D is arranged in the upper space. The switching contact part B and excess current detecting part C are arranged in the lower space. F is an operatively connecting plate integrally having an armature for transmitting the operation of the excess current detecting part C to the operating part D. F is a carrier for transmitting the operation of the operating part to the switching contact part. The electric current path is from the input terminal through the switching contact part B and excess current detecting part C to the output terminal OUTPUT. The operation sequence is from the excess current detecting part C through the operatively connecting plate F, operating part D and carrier F' to the switching contact part B. G is a handle. The operating part D is manually operated by the handle G so as to make ON and OFF.

FIG. 2 shows an upper surface view, in which 57 is a handle to be rotated so as to have three positions of U, V, and W within a fan-shaped concave part 68 pro.- vided on a cover 65. The trip is indicated by a red mark appearing in an indicating window hole 62 made on the upper surface of the case. is a set screw used to fit the cover 65 to the chassis.

FIG. 3 is a lower surface view showing the circuit breaker of the present invention with the bottom plate removed. Thin parts 69 are provided on the side wall 65a of the cover 65 so that electric wires 66 may be inserted and fitted within the unit by removing said parts. I is a chassis, and 64 is its lower lid.

FIG. 4 shows a side view of the circuit breaker. A handle 57 is rotatably provided on the cover 65. 69 is a thin part.

FIG. 5 shows a vertically sectioned view of the above. The electric wires 66 are fitted to the chassis 1.

FIG. 6 is an upper surface view of the device in FIG. 1 shown with the cover 65 removed. 5 and 6 are respectively an input terminal and output terminal. A fanshaped indicating plate 63 is fixed integrally with the handle 57 to the lower part of the handle 57. A trip indicating part 630 is provided on this indicating plate so that, with the rotation of the handle 57, the trip indicat- .ing part 63a will move and that, when the indicating part 63a is positioned below the indicating window hole 62 of the lid 59, the trip state will be indicated. 59b is a concave part made on the upper lid 59. 59C. is an edge of the lid.

FIG. 7 is a view showing the interior of the device shown in FIG. 6 with the upper lid 59 removed.

In the drawing, the operating part D is secured between both side walls 2 of the chassis 1. There are shown a carrier F (indicated by 22 in the drawing) operated by said operating part D and an operatively connecting plate F (indicated by 25 in the drawing) operated by the excess current detecting part C.

FIG. 8 is a view shown in FIG. 3 with the lower lid 64 removed. There are shown the excess current detecting part C, switching contact part B and operatively connecting plate F (25) operated by the excess current detecting part C. 1

FIG. 9 is a vertically sectioned view of the device of the present invention and is a detailed view corresponding to FIG. 1. There are shown the input terminal a(5 switching contact part B, excess current detecting part C, operatively connecting plate F, operating, part D, carrier F and output terminal b(6). The excess current detecting part C and operating part D are arranged as separated above and below the partition wall E(3) of the case. j

FIGS. 10A through 10C show a chassis A(I), wherein FIG. 10A is an upper surface view thereof. The operating part D (not illustrated here) is fitted in the space between the side walls 2. 71 is a hole for fitting the operating part D. The space is sectioned into an upper space and lower space by a partition wall 3. 72 and 73 are communicating windows made in the partition wall 3.. The carrier F (not illustrated here) is inserted into theicommunicating window 72 and the operatively connecting plate F (not illustrated here) is inserted into the communicating window 73. FIG. 10B is a lower surface view. The communicating

windows

72 and 73 are seen between the side walls 2. 74 is a partition wall for housing the elements forming the excess current detecting part C as described later. FIG. 10C shows a vertically sectioned view of the chassis. There are shown the partition wall 3 and communicating

windows

72 and 73.

FIG. 11 is a sectioned view of the device along the communicating window 72, wherein the carrier 22 (or F) is shown here.

Now the formation of each part shall be detailed.

FIG. 12 shows an operating part unit. FIG. 13A

shows the respective elements thereof as disassembled in a perspective view. The above described operating part D is held between two

ground plates

33 and 33'. 39 is an arcuate groove made in the ground plates. 75 is a hole made in each ground plate, in which the long leg 37a of a later described U-shaped shaft 37 is pivoted. Said U-shaped shaft 37 has a long leg 37a and short leg 37b. In an operating plate 38 formed to be U- shaped by bending two plates, there are formed two

holes

38a and 38b and a calked pin 38c inside. The long leg 37a of the shaft 37 is inserted through the hole 38a of the operating piece 38 and is inserted into the hole of the ground plate 33. The short leg 37b is inserted into the hole 38b of the operating piece through a roller 76 contained inside the operating piece 38 (see FIG. 12). That is, the operating piece 38 is fitted to the ground plates 33 and 33' so as to be rotatable with the shaft 37a as a center. 40 is a turning arm provided with a tip part 40a as somewhat inclined at one end, with a hole 40c at the other end and with a projection 40b in the substantially intermediate part. A shaft 41 is inserted in the hole 40c of the turning arm 40. Further, the turning arm 40 is inserted in the intermediate part (between the hole 400 and projection 40b) into the intermediate part (between the hole 38b and pin 38c) of the operating plate 38 (see FIG. 12B). 42 is a hanging frame bent to be a U-shaped. 42a is its connecting part. 42b is a pivoting hole. The hanging frame 42 has at its tip engaging parts 44 with which the shaft4l of the turning arm 40 is to be engaged and inclined parts 45. The ground plates 33 and 33' are combined with each other with a fixed space between them by inserting the projections at both ends of calked rivets 34 into the holes 330 and 33'a. The operating plate 38 is rotatably supported between both ground plates with the long leg 37a of the U-shaped shaft 37 inserted in the holes 75 of the ground plates 33 and 33'. The hanging frame 42 is rotatably supported by the ground plates with a shaft 43 inserted in the hole 42b of the hanging frame and the holes 33b and 33'b of the ground plates. 49 is a re- 1 sponding piece formed to be substantially L-shaped and having a bent part 49b formed at one end, a pivoting hole 49c formed at the other end a projection 52 formed on the side opposite the bent part 49b. The responding piece 49 is rotatably supported between the

ground plates

33 and 33 by inserting a shaft 50 in the hole 490 of the responding piece 49 and the respective holes 330 and 33'c of the ground plates 33 and 33'.

The above mentioned responding piece, hanging frame and turning arm areso arranged that, as shown in FIG. 13B, the

tip parts

49a and 52 of the responding piece 49 will-be engageable with the bent part 42a of the hanging frame 42 and the shaft 41 inserted in the hole 400 of the turning arm 40 will be contactable with the engaging part 44 and inclined part 45 of the hanging frame 42. A spring 51 is inserted between the projection 54 of the responding piece 49 and the bent projection 53 of the ground plate 33 so as to give a counter-clockwise pressing force to the responding piece 49. A spring 56 is engaged at one end with the short leg 37b of the U-shaped shaft 37 and at the other end with the hole 33d of the ground plate 33 so as to give "a clockwise torque to the operating plate 38. 46 is all shaped spring inserted at the open end 46b in the holes 48 of the

ground plates

33 and 33,-engaged in the intermediate part 46a with the cut and raised parts 47 of the ground plates 33 and 33' and contacted at the other end 46c with the sides 44d of the engaging parts 44 so as to give a clockwise torque to the engaging parts 44. The thus formed state is shown in FIGS. 14A through 14C, in which FIG. 14A shows a front view of the operating part. FIG. 14B shows its rear view and FIG. 14C shows its side view.

FIGS. 15 and 16A through 16C show an oil dash pot type electromagnetic device employed as an excess current detecting part. It is formed of a coil 17, coil frame 18, L-shaped yoke 20 and oil dash pot 20'.

FIG. 17 shows a switching contact unit, in which a movable contact 13 is provided at the tip of a contact plate 12, a hole 12a is provided in the intermediate part, a middle leg a of an E-shaped supporting metal piece 10 is inserted in the hole 12a, the contact plate 12 is embraced on the sides by hooked parts provided at the tips of both legs 10b and 100 and the contact plate 12 is supported rotatably on the supporting metal piece 10 by a coil spring 77 fitted on the middle leg 10a. 78 is a terminal metal piece connected with the contact plate 12 through a lead wire 15.

FIG. 18 shows the carrier 22 (or F) in which grooves 22a for inserting the contact plate 12 are made on the lower side and a stepped part 24 to contact the turning arm 40 is made on the upper side as described later.

FIG. 19 is of an operatively connecting plate to which is fixed an armature 25 formed of a turning plate 27, to the lower side of which is fixed an iron piece 26 with a pin 29 and in a part of which is provided a projection 25' to push the bent part 4% of the responding piece 49. 30 is a supporting shaft provided to project at each end of the operatively connecting plate so as to rotat ably fit the plate to the chassis 1 as described later.

FIGS. 20 and 22 show the handle 57 made of a synthetic resin. 57a is a hole in which the long leg 37a of the U-shaped shaft 37 is to be inserted and which is made through the handle 57. 57b is a hole in which the short leg 37b is to be inserted and which does not pass through the surface.

Now the assembly of the device of the present invention shall be explained.

The

respective leg parts

5b and 6b of the L-shaped input terminal metal piece 5 and output terminal metal piece6 are inserted respectively in the concave parts In and lb of the chassis I (see FIGS. 7, 8, 9 and 10) made of an insulator. Wire fastening screws 7 are fitted to the respective upper pieces 5a and 6a of the

terminal metal pieces

5 and 6 and a fixed contact 9 is provided on the leg part 5b of the input terminal metal piece 5.

Then, the opening on the back surface of, the chassis (FIG. 10B) is directed upward and the stepped part 24 of the carrier 22 (FIG. 18) is inserted in the communicating window 72 of the chassis I, then the supporting metal piece 10 (FIG. 17) of the contact plate 12 is inserted in the concave part 1d (FIG. 10B) of the chassis and the metal piece v78 is inserted in the groove 1e of the chassis to fit the contact plate. Then the coil frame 18 of the electromagnet (FIGS. 15 and 16) is inserted between the wall parts If and 1g of the chassis to fit the electromagnet, and the coil 17 is soldered in the end part 17a to the

metal pieces

78 and 66. Then the back lid 64 is secured to the bottom surface of the chassis.

Thus the assembly of the electric parts through the opening on the back surface of the chassis is completed. Then the opening on the front surface of the chassis (FIG. 10A) is directed upward. First, the hole 71 is aligned with the hole 33 of the ground plate of the completed operating part (FIGS. 12 and 14) and the operating part is fixed to the chassis with the rivet 36 (FIG. 21). Then the operatively connecting plate 25 is fitted. The indicating plate 63 indicating the trip is fitted to the U-shaped shaft 37, then the upper lid 59 is secured to the upper surface of the chassis l, the

long legs

37a and 37b of the U-shaped shaft 37 are inserted respectively in the

holes

57a and 57b (FIG. 20) of the handle 57, a lock washer 57b is fitted to the upper part of the long leg 37a, a lid 79 is fixed above the long leg 37a (FIG. 22) and a case is applied (FIGS. 3 and 4). Now the operation of the device according to the present invention shall be described in the following. i. FIG. 23A shows the contact in the OFF-state in which the contact plate 12 is separated from the fixed contact 9 (see FIG. 24A). In this case, the handle 57 is in the position of W in FIG. 2 and the indicating plate 63 is in the position of W in FIG. 6. In this case, the projection 52 of the responding piece 49 is engaged with the end part 42b of the hanging frame 42 and the shaft 41 of the turning arm 40 is positioned at the left end ofthe arcuate groove 39 of the ground plates 33 and 33' and is engaged with the inclined part 44b of the hanging frame 42. ii. When the handle 57 is rotated counterclockwise so as to be in the state shown in FIG. 23B (the handle position is in the state of U in FIG. 2), the handle will rotate with the shaft 37a as a center, the operating plate 38 will also rotate together with thehandle, and the upper end part 40a of the turning arm 40 will rotate clockwise with the shaft 41 as a center. Therefore, the carrier 22 will move rightward against the resiliency of the spring 14 and, at the same time, the contact will move toward ON against the resiliency of the spring. At this time, in case the roller (of the roller'bearing) slides while under the reaction on the projection provided on the turning arm and passes the apex of the projection, the displacement of the operating plate will. become maximum. When the U-shaped arm 37 further rotates and the roller lowers down the slope of the projection, the carrier 22 will somewhat return to the OFF side. In this state, the spring 56 to return the handle will give a force to move the turning arm to the OFF side but, by overcoming it, a stable state will be made and the ON state will be obtained, because a dead point is formed at the projection 4b of the turning arm. iii. If an excess current flows in this state (see FIG. 9), the attracting iron core 19 of the electromagnet will attract the armature 25 and the contact will be OFF so as to be in the trip state. Its details are as follows.

Now, by the resiliency of the spring 14, the carrier 22 will be pushed toward OFF side and this force will give a clockwise torque component to the slope 44b of the hanging frame 42 through the turning arm and to the hanging frame 42 through the shaft 41 of the turning arm and will give a torque. When the responding piece 49 and the frame are disengaged from each other, the hanging frame 42 will escape clockwise and will be disengaged from the turning arm 40 and the shaft 41 of the turning arm will move counterclockwise with the contact point of the roller and turning arm 40 as a rotation center along the groove 39. Therefore, the carrier 22 will move to the OFF side due to the resiliency of the spring 14 and the contact will be in the OFF state. At this time, a counterclockwise force (toward OFF) will be given to the operating piece 38 by the handle spring 56 through the U-shaped shaft and the operating piece 38 will rotate. However, so that the handle may

Claims

1. An operating mechanism for driving switching mechanism in circuit breaker having trip-indicating means comprising two ground plates connected as spaced with each other and respectively having an arcuate groove opposing one another, an operating plate provided with vertical plates parallel with each other and with two fulcrum means set between said vertical plates, said operating plate being rotatably pivoted between said two ground plates by means of a shaft penetrating through the vertical plates at one end thereof, a turning arm having at one end a shaft fitted movably in said opposing arcuate grooves of the ground plates and at the side part a cam lobe, said turning arm being loosely fitted in the middle part between said two fulcra of the operating plate and contacted in the other with a carrier communicating the operating mechanism with the switching mechanism for driving contacts in the latter so that the side part of the arm will be pressed against one of the fulcra of the operating plate by a returning force of said carrier, a hanging frame rotatably pivoted between said two ground plates so as to engage and restrain said shaft of the turning arm at one end within said arcuate grooves in response to situations of the circuit and a responding piece rotatably pivoted between said two ground plates so as to release the engagement of the shaft of turning arm with the hanging frame upon rotation due to a force transmitted to the responding piece from an electromagnetic device in the switching mechanism actuated when the circuit is in abnormal state, the arrangement being in such that, when the contacts are in ON state, the shaft of the turning arm will be engaged with the hanging frame, the cam lobe of the turning arm will engage the fulcrum of the operating plate and thereby the other end of the turning arm will be pushed toward the ON state of the contacts against the returning force of the carrier, when the contact is in the trip state, the turning arm will be disengaged from the hanging frame and will be stably held in the trip position by the twisting force between the two fulcra of the operating plate and, when the contacts are in OFF state, the shaft of the turning arm will be engaged with the hanging frame, the side of the turning arm will contact the fulcrum of the operating plate and the carrier will remain in the OFF position of the contact.

2. The operating mechanism according to claim 1 wherein said shaft of the operating plate extends at one end out of the ground plate so as to be adapted to pivotally support an operating handle of the circuit breaker.

3. The operating mechanism according to claim 1 wherein said shaft of the operating plate is formed in a U-shape, one leg of said U-shape being the pivot for the operating plate, the other leg of said U-shape sHaft is penetrating through the ground plates and the vertical plates of the operating plate so as to act as one of the two fulcra, and both legs extend out of the ground plate so as to support an operating handle of the circuit breaker in such that the one acting as the pivot shaft for the operating plate will be a pivot shaft for the handle and the other acting as the fulcrum will be a rotation transmitting means between the operating plate and the handle.

4. The operating mechanism according to claim 3 wherein said the other leg of the U-shape shaft acting as a fulcrum of the operating plate is provided with a roller mounted therearound at the fulcrum position.

5. The operating mechanism according to claim 1 wherein said force from the electromagnetic device is transmitted to the responding piece with a larger leverage than that of the hanging frame with which the frame engages the shaft of the turning arm for restraining the arm at the one end position in the arcuate grooves of the ground plates, and said engagement of the hanging frame with the turning arm shaft is established at an inclined surface provided in the frame, said inclined surface forming an obtuse angle with respect to moving direction of the turning arm shaft in the grooves, so that said transmitted force to the responding piece is further transmitted to the hanging frame as enlarged by said larger leverage and the restraining of the turning arm shaft is readily released due to the inclined surface of the hanging frame.