US2414956A - Electromagnetic switch - Google Patents

Description

w. D. KYLE, JR., ETAL ,956

ELECTROMAGNETI C SWITCH Jan. 28, 1947.

2 Sheets-Sheet l Original Filed June 6, 1941 Jan. 28, 1947.

w. D. KYLE, JR, ErAL 2,414,956

ELECTROMAGNETIC SWITCH Original Filed June 6, 1941 2 Sheets-Sheet 2 I I/IIIII/IlIl/II/Ilh 111/1/21]!//////////7/////. I/l/l/l/l/l/I/l/l/I I/l/l/II/I/l/I/llll/ll/l/////l/////////////Z INVENTORS Maw/14 fi Km 0;". By 0m Jaw/mm 2 it-fa 147' ORA E )2 Patented Jan. 28, 1947 UNITED STATES PATENT orrica ELECTROMAGNETIC SWITCH Williani D. Kyle, in, Milwaukee, and Carl Schindler, Wauwatosa, Wis., assignors to Kyle Corporation, a corporation of Wisconsin Original application June 6, 1941, Serial No. 396,850. Divided and this application July 22, 1943, Serial No. 495,682

Claims. (01. 200-111) 2 load terminals which are carried by insulating bushings one of which is shown and indicated by the reference character ill.

The automatic reclosing circuit breaker is suspended in its entirety from the metal cover 2.

- The circuit breaker is provided with the electrotacts are provided which receive the final arc and I thus avoidany injury to the main contacts, the construction being such that the circuit breaker will always operate at its predetermined overload value irrespective of the length of time it may have been in operation or the number of times that it has operated.

Embodiments of the invention are shown in the accompanying drawings, in which:

Figure 1 is a side elevation, partly broken away and partly in section, of the automatic reclosing circuit breaker.

Figure 2 is a fragmentary sectional view on the line 22 of Figure 1.

A convenient way of attaching the top to the can a is by means of a plurality of bolts 3 which are pivotally mounted between spaced ears 4 carried by the can and which are provided with wing nuts 5. The wing nuts are adapted to bear against L-shaped clamping plates 6 whose downwardly extending portions are adapted to rest upon the upper faces of the ears 4, a suitable lug I being provided on each of the ears to prevent the clamping plates 6 from sliding on the upper surface of the ears 4. A suitable sealing gasket, not shown, is positioned between the can and the cover.

Any suitable attaching means as indicated at I 8 and 8 are provided on the can so that the can may be attached to a pole or other suitable sup- P rt.

The cap or cover 2 is provided with line and magnetic coil or solenoid II which surrounds an insulating tube or sleeve I2.

A non-magnetic operating rod I 3 for the cir cuit breaker extends upwardly centrally of the insulating tube l2 and on this rod a plunger i4- of magnetic material is freely slidable.

The operating rod [3 of the circuit breaker rigidly carries a spider like stop [5 which loosely fits within the sleeve l2 and which serves as an abutment against which the upper end of the, magnetic plunger l4 strikes when the coil H is energized by an overload current. When this occurs, the plunger I4 is suddenly drawn upwardly into the coil and strikes the abutment l5, carrying the rod i3 upwardly.

The lower end of th rod i3 is rigidly secured to an insulating cross-head I 6, see Figure 2. The cross-head It carries a pair of contact rods H to which are rigidly attached a pair of contact sleeves l8, see Figures 2 and 3. The contact sleeves l8 normally engage the stationary contact pins l9. These stationary contacts or con.- tact pins l9 are connected to the line and load terminals of th circuit breaker.

It is to be noted particularly with reference to Figures 2 and 3 that the stationary contact pins l9 constitute stops against which the lower ends of the contact rods l'l abut when the circuit breaker is closed.

It is preferable to make the contact pins or stationary contacts [9 split as shown in Figure 3 and to have the movable contacts or sleeves l8 engage the pins [9 with a wiping motion to insure a clean contact at all times. The arcing upon separation of. the movable and stationary contacts does not occur between the sleeves I8 and the pins H! but separate arcing contacts are provided in the form of conducting rollers 20 which may be of metal and which are carried by 'leaf springs 2| clamped in place as shown in Figure '3. These arcing contacts 20 are the last members that engage the movable contacts l8. All the arcing occurs between the arcing contacts 20 and the outer-surfaces of the sleeves l8, thus maintaining the inner surfaces of the sleeves and the outer surfaces of the pins in good condition free from pitting although the circuit breaker may have operated a great number of times.

The arcing contacts are readily renewable and it is also easy to renew 3 the sleeves !8, if this becomes necessary, by driving out the locking pin or other suitable securing means 22, see Figure 3,

and replacing the old sleeves with new sleeves. This very rarely happens, however, for the arcing occurs, as stated, between the outer. surfaces of the sleeves I8 and the arcing contacts 28.

It is to be noted particularly that the upper ends of the stationary contacts or plus is form a definite stop for arresting the downward motlon of the movable portions of the circuit breaker and consequently the circuit breaker, together with the magnetic core or plunger I4, see Figure 1, will always come to rest at exactly the same point so that the circuit breaker will always respond to the same current.

' If. on the other hand, the active contact had been a butt contact and the arcing had occurred between butt contacts there would be a gradual wearing away of this contact through continued use of the circuit breaker and consequently the circuit breaker would operate only at an increased current as the time of service increased. However, in the invention herein'described, the circuit breaker 'will always respond at exactly the same predetermined value of overload current. 9

The contact rods I! are connected by flexible leaders 23 with opposite ends of the coil ll so that the coil H is in series between the line and load terminals and directly across the movable contacts i8.

It is preferable to encase the lower portion of the circuit breaker, that is to say, the stationary and movable contacts, within an insulating cylindrical sleeve 24. The upper end of the sleeve 24 is closed, except for passageways which form no portion of the present invention, by means of the collar or member 25 and the lower end'of the sleeve 24 is closed by means of the basamember 26. The base member is provided with an oil inlet opening 21, see Figure 1, which is normally closed by a downwardly seating fiap 28.

As will be seen from Figure-2, the insulating base member 26 is suspended by means of the insulating rods29. These rods extend upwardly to the portion 25 and are internally threaded at their upper and lower ends to receive the bolts to thereby lock the rods in place and to the base 26. The insulating sleeve or shell 24 is therefore clamped between the insulating head or collar 25 and the insulating base 26.

It is preferable to provide insulating partitions extending upwardly between the spaced contacts. These partitions may take the form of two members 30 of insulating material which have integrally formed, outwardly bent foot portions 3|, see Figure 2. The foot portions are clamped in place by the stationary contacts. The member 30 may be in contact with each other, as shown in Figure 2, or may be spaced apart, as shown in Figure 4, or'may be spaced apart at their lower ends and may approach each other or be in contact at their upper ends, as shown in Figure 5.

By having the base or foot portions 3| of the members or b'aflles 30 integral with the vertical portions thereof, it is apparent that any conducting'sediment that may settle down between the stationary contacts will notform a bridge path from one contact to the other. Further, in view of the fact that the members 3|! and 3! are integral, it is apparent that no conducting sediment can form and'lead up to a shortgap across which the arc would strike.

In Figure 4 a different form of insulatin baf- 75 .70 load terminal.

g fie has been illustrated. These bafles have t e same shape as those previously described a d consist of the vertical portions 32 and the hori-= zontal foot portions 33, but these bafiles are shown in Figure 5, in which the upright portions of the insulating baifles are indicated at as and the foot portions or horizontal portions at 35. The upstanding portions 34 may engage each other at their upper ends but are spaced at their lower ends to provide an oil space.

The circuitbreaker is automatic in its operation and is adapted to look out after a certain number of operations and has oil cushioning means and oil pumping means and automatic and manual trip means, as well as manual reset means, but inasmuch as these features form no portion of this invention, a description and disclosure thereof has been omitted. These fees I tures are, however, as set forth in our companion case hereinbefore identified of whichthis application is a division.

Sufllce is to say that when an overload occurs, the plunger I4 is drawn upwardly and strikes the spider like stop It rigid with the rod l3 and raises the cross-head l6, which raises the rigidly attached contact rods H and consequently moves the movable contacts or sleeves it from the stationary contacts or pins IS, the last contact being established through the outer surface of the sleeves l8 and the arcing contacts 26, the arcing,

therefore, being confined '-to the outer surface of 35 the sleeves l8.

-It is apparent that for any given winding or solenoid II the minimum overload current at which the plunger It will be drawn upwardly into I the solenoid will be determined by the position 40 of the upper end of the plunger it within the solenoid. Consequently it is desirable to always bring the plunger H to rest at exactly the same point when the circuit breaker is closed. This is ting contact surfaces, there is scarcely any mechanical wear whatsoever, and therefore even after the circuit breaker has been in use fora long period and has operated a great many times, nevertheless it willalways open for the predetermined minimum overload current.

It is also apparent that in the event the outer surfaces of the sleeve l8 or the arcing contacts 20 may have become seriously pitted, they can be most easily renewed.

In the form of the invention shown in Figure 4 a metal cross-head It has been provided and is rigidly attached to the metal rods H. with this type of construction the two stationary contacts are connected respectively to a line terminal and to one side of the solenoid i I, the other side of the solenoid i! being connected to the Although this invention has been described in considerable detail, it is to be understood" that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

accomplished by having the contact rods l1 abut, the upper ends of the stationary contacts or Pins 5. we claim: 1. A circuit breaker comprising a stationary contact and a movable contact. and electromagnetic means for moving said movable contact closed irrespective of the wear on the contacts due to arcing, said contacts having slidably engaging portions constituting wiping contacts for carrying the current.

2. A circuit breaker comprising a stationary contact and a movable contact, and'electromagnetlc means for moving said movable contact away from said stationary contact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stopmeans to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcing, said contacts having slidably engaging portions constituting wiping contacts for carrying the current and one of said contacts having arcing contact means for engaging the outer side of the other contact to locate the final arc at a point spaced from both the stop means and the slidably engaging portions.

3. A circuit breaker comprising a stationary contact and a movable contact, electromagnetic means for moving said movable contact away from said stationary contact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcing, one of said contacts being in the form of a pin and the other of said contacts being in the form of a sleeve having sliding engagement with the pin to provide the current carrying portions of said contacts.

4. A circuit breaker comprising a stationary I contact and a movable contact, electromagnetic means for moving said movable contact away from said stationary contact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcing, one of said contacts being in the form of a pin and the other of said contacts being in the form of a sleeve having sliding engagement with the pin to provide the current carrying portions of said contacts, the contact in the form of a pin having an arcing contact adapted to maintain engagement with the outer surface of said sleeve for an instant after said sleeve and pin have separated.

5. A circuit breaker comprising a stationary contact and a movable contact, electromagnetic means for moving said movable contact away from. said stationarycontact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcin one of said contacts being in the form of a pin and the other of said contacts being in the form of asleeve having sliding engagement with the pin to provide the current carrying portions vo1 said contacts, one of said contacts being split. I

6.'A circuit breaker comprising a stationary contact and a movable contact, electromagnetic means for moving said movable contact away from said stationary contact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcing, one of said contacts being in the form of a pin and the other of said contacts being in the form of a sleeve having sliding engagement with the pin to provide the current carrying portions of said contacts, a pair of leaf springs on opposite sides of said pin, and arcing contacts carried by said leaf springs and adapted to grip said sleeve between them and maintaining contact with the outer surface of said sleeve for an instant after said sleeve and pin have been separated.

'7. A circuit breaker comprising a stationary contact'and a movable contact, electromagnetic means for moving said movable contact away from said stationary contact including a coil and a cooperating armature, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said armature and coil when said contacts are closed irrespective of the wear on the contacts due to arcing. one of said contacts being in the form of a rod with a sleeve surrounding and extending from the outer end thereof, and the other contact being in the form of a pin slidably receiving said sleeve when said contacts are closed and constituting the current carrying portion of said contacts, the rod and pin having ends adapted to abut to determine the initial position of said armature with reference to said coil} 8. In a switch construction, switch means including a stationary contact and a movable contact, and means for moving said movable contact with reference to said stationary contact, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said movable contact and said stationary contact when said switch means is closed irrespective of wear on the contacts due to arcing, one of said contacts being in the form of a pin and the other of said contacts being in the form of a sleeve having sliding engagement with the pin to provide the current carrying portions of said contacts, the contact in the form of a pin having an arcing contact adapted to maintain engagement with the outer surface of said sleeve for an instant after said sleeve and pin have separated.

9. In a switch construction, switch means including a stationary contact and a movable contact, and means for moving said movable contact with reference to said stationary contact, said stationary contact and said movable contact having abutting portions constituting stop means to maintain a predetermined definite relation between said movable contact and said stationary contact when said switch means is closed irrespective of. wear on the contacts due to arcing, one of said contacts being in the form of a rod with a sleeve surrounding and extending from y y Y the outer end thereot and the other contact being in the form of a pin slidably receiving said sleeve when said contacts are closed and constituting the current carrying portion of said contacts, the rod and pin having ends adapted to abut'to determine the position or said movable contact with reference to said stationary contact when said switch means is closed.

.10. A. switch construction comprising a stationary contact and a movable contact, and

means ior moving said movable contact with

Images