DE1197539B - Electric toggle switch - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

HOIh

German class: 21c-68/01

Number: 1197539

File number: F 33918 VIII b / 21 c

Filing date: May 13, 1961

Opening day: July 29, 1965

The invention relates to electric toggle auto switches with thermal and magnetic overcurrent release, their contacts in the on position be held via a knee joint by a latching lever, which is held by a disengageable Stop of the release device is locked.

There are already overcurrent self-switch with toggle lever mechanism known in which a rolling There is contact on a surface while there is frictional contact on the shaft of the roller. At high currents, however, high frictional forces result in such an arrangement the bearings, which results in significant disadvantages for the entire switching arrangement.

A trip-free mechanism for circuit breakers is also already known in which a ball bearing arrangement is provided, which acts as a locking element and in which a sliding movement occurs.

Furthermore, electrical circuit breakers with magnetic quick release are known in which the Magnetic armature is guided along its entire course of movement and in which consequently the magnetic field must reach a high value. When the magnetic field strength is lower Has value, the anchor is only guided along part of its course of movement. By Changing the spring, which holds the armature in its rest position, can change the operation of the arrangement change. With such an arrangement, a kind of snap action is achieved.

The object of the invention is to provide a small and compact switch for high current carrying capacity to specify. To achieve this, a high temperature rise in the housing must be avoided will; However, so that high rated currents can flow, a high contact pressure must be achievable. The high current carrying capacity also depends essentially on a good heat transfer from the current-carrying ones Divide the switch together to form the bimetal strip. The triggering of the switch is intended can be achieved by a relatively small increase in temperature, so that only a relatively small mechanical force is to be applied by the current-sensitive bimetal strip. So that the actuation force for triggering the device in the event of an overload is as low as possible, a largely frictionless ratchet mechanism provided for the contact actuating device , whereby a practically smooth tripping in the event of overcurrent is to be achieved at the same time. According to the invention, a rocker arm self-

Electric toggle switch

Applicant:

Federal Pacific Electric Company, Newark, N.J.

(V. StA.)

Representative:

Dr.-Ing. W. Reichel, patent attorney,

Frankfurt / M. 1, Parkstrasse 13th

Named as inventor:

Alfred E. Maier, Colonia, N. J .;

Henry S. Wingard, Cranford, N.J. (V. St. A.) -

Proposed switch of the type specified above, in which the overcurrent release device is a movable Bearing member and a roller arranged between the latching lever and the bearing member which is in rolling contact with both parts on opposite sides of the roller, further moves the current-sensitive device when responding to the bearing member in such a way that the Roll on the bearing link and the latch lever practically unrolls smoothly and the switch triggers.

In such an automatic switch, according to a particular embodiment, the current-sensitive one runs Device forming bimetal strips along a current-carrying bracket, between a At the end of the bimetal strip, there is good heat transfer to the bracket and the overcurrent release takes place with a relatively small increase in temperature of the bracket. Preferably has the overcurrent release device on a pivotable armature, which by a spring of its magnetic core is biased away, the line of attack of the force exerted by the spring runs in the Near the axis of rotation of the armature, and there is a common means provided through which the magnetic gap distance and the position of the end of the spring further away from the armature adjustable are, so that the line of attack of the spring is moved relative to the axis of rotation of the armature, this Settings at the same time the magnetic release

509 628/34 *

3 4

Increase the sensitivity of the switch or shaft ends 40 of the square shaft 38 are humiliate. rotatably mounted.

An embodiment of a switch according to the The two toggle levers 42 and 44 are rotatably

Claims will be attached to her knee 46 in conjunction with the other below. The lower lever Drawing explained. 5 42 is rotatable on the contact carrier 36 of the middle

F i g. 1 shows a side view of a switch pole hinged, the upper lever 44 on a releasable one according to the invention, partially in section, so that the latching lever 48, which is normally through the inner structure becomes visible. The switch is held back in its overcurrent release device 50 The latch lever 48 has a pivot 54 transmission mechanism is shown in the position in a frame 52 in io. A two-armed, by hand he lever 56 to be actuated by the release mechanism in the event of an overload is rotatable on his is latched; stored lower end. Four feathers 58, one of which

F i g. 2 shows a corresponding plan, only two of which are shown, are between the knee 46 Parts are shown broken away so that the interior of the knee joint and the actuating lever 56 are constructed becomes visible; 15 cocks. A handle 60 made of insulating material is with the

F i g. 3 shows a partial view of a modified operating lever 56 connected and reaching through Execution form of a bracket and a slot in the cover 10 so that it can be loaded from the outside

F i g. 4 an enlarged section of a page can be activated. This handle has lateral approaches, the view from the details of the latch to recognize the slot in all positions of the handle,
are. ao The over-center spring and knee in the drawing is a switch with an insulating press-joint mechanism, is shown in the drawing in its material housing, which shows a cover 10 and open state. When the one base part 12 is actuated. The two parts are in handle 60 to the left (FIG. 1), the springs are usually attached to one another in such a way that they are tensioned, so that the knee joint is stretched and some contacts, the actuating mechanism and the auto-25 are guided beyond this position is, whereby the matic tripping device in case of overload around contacts of all three poles are closed. In the close. The terminals 14 and 16 are externally connected state of the switch and when the circuits, between which an approximately rectilinear current ratchet mechanism 15 lies the latching lever 48, which releases from the terminal 14 via the conductor, the latching lever swings against 18, the fixed contact 20, the movable contact 30 clockwise past the line of attack of these springs 22, the flexible, electrically conductive strand 24 and the bracket, whereby a buckling of the knee 26 leads to the clamp 16. The bracket 26 is pre-articulated and an opening of the contacts occurs,
preferably as a one-piece copper bracket with a rectangular

shaped cross-section. He owns in the act is known.

Near the terminal 16, lead a lightly upwards. 35 The overcurrent release device 50 is in the the shoulder so that the terminals 14 and 16 form in the same housing as the current paths equal distance from the bottom of the switch included parts of the relevant poles. The include. Two fastening screws 28 connect individual current-sensitive devices of the verden Bracket 26 mechanically with the base part 12, so different poles are shared by one that a displacement of the bracket 26 is avoided. 40 clutch lever 62 connected at its end

The conductive stranded wire 24 contains an attached to it in the base part 12 is mounted. The surface of the welded part flat connector 24 'made of thin ratchet lever 48 pushes up against the roller Copper. The screw 30 engages through holes in the 64, whose end parts are tapered in their diameter Ladders 26 and 26 ', creating good contact between pressing up against two bearing members 66, the these elements along a very large area 45 with upper inner lugs of the clutch lever 62 arises. Parts 24 'and 26 are silver plated to be riveted (Fig. 2). These tapered end portions of the the contact resistance can be reduced at this point - the ratchet roller can be set between horizontal limits set. The screw 30 pushes the fixed end working through the walls of opposite, of the bimetal 32 against the bracket 26. Recesses 68 formed in lugs 70 therebetween are fixed a washer 34 around the contact pressure 50 are placed. The arms of a U-spring 72, which is attached to the maintain. The bimetallic strip 32 extends clutch levers 62 are attached, give a Vorin its entire length very close to the bracket 26 tension to the right for the roller 64. Therefore rolls and is at normal temperatures and when not when the clutch lever 62 is rotated clockwise flows in the bracket 26, tightly against the bracket 26. sense the roller 64 with practically no friction between The side of the bimetal strip 32 with large extension 55 the bearing surfaces of the latching lever 48 and tion lies on the bracket 26, so that this is at the bearing members 66 in such a direction that Deflects heating upwards. the latch lever 48 is released to the

Like F i g. 2, contacts are to be opened for the switch. The spring 72 is proportionate three adjacent poles provided. Each weak and serves the appropriate attitude Pole has a current path consisting of the elements 60 of the roller 64 during the return process, elements 14, 18, 20, 22, 24, 26, 16. In addition, if the switch is overloaded, it will not trip the spring and tilt mechanism in the middle follows.

mus provided in the middle pole to make the movable the return is done with the help of the handle 60

To operate contacts 22 of the three poles mechanically. from its "on" or "release" position Each movable contact 22 is resiliently provided by a 65 on the right so that it rests against the projection 48 'of the latching contact carrier 36 added, which in turn attacks with hebeis 48 and the latter in a clockwise direction square, isolated shaft 38 connected against a reset lever 62 'of the release, which goes through the whole switch. The Hebei leads. The resulting rotation

5 6

the release lever counterclockwise leads to move high current, it works with a

the individual current-sensitive devices of the snap action. The line of attack of the spring 102

three poles back to their starting position. does not cross point 100, so the anchor goes through

For each pole there is a magnetic and thermal spring which is returned when the overload

current-sensitive device provided. Every 5 electricity is interrupted.

of these devices has a frame 74, which the stop 104 is adjustably fastened to the base part 12 by a shaft. The frame 74 108 received, which rotatably carries a spring lever 76 on the top of the, which rests against the frame 74. At the lower end, the clockwise direction is screwed into the stop 104 by a spring 78 on the frame shaft 108. A part 80 is biased. The spring lever 76 is pre-tensioned by the compression spring 112, the stop 104, the shaft of an adjustable screw 82 on a rotatable 108 and the head 110 downwards. Latched latch member, which is designed as a bimetal 84 compensating for the temperature on the top of the knurled head UO. An adjustment knob 114 is frictionally attached, in locking engagement between the screw 82 and which is provided with a slot 116 so that a spring lever 76 results in a force which can be used along a screwdriver. A line that acts through the pivot bearing 86 in the right button at the point 114 integrally therewith at an angle to the line between the point of the locking-bound lug 118 can be brought into engagement with a fixed engagement and the axis of rotation 88 of the latched stop 120 will. This is spring lever 76 runs. The biased lever 76 attached to the lid 10, whereby the rotation of the pivoted pawl 82 is not operated to 84 in 20 of the knob 114 to a range of about 300 ° release direction. The bimetal element 84 can be limited. As a result, the position of the stop is set to be relatively thin and therefore very sensitive 104 . This arrangement results in the being designed, since it is only subjected to train. The pretensioned spring 90, which lies against an iso-magnetic release setting, leaning holder 92, biases the bimetallic element 25 with the cover 10 removed and before the 84 counterclockwise, ie in the Rieh- fastening of the switch Knob 114 in the position shown device, the correct position of the screws 82 over the shaft 108 can be adjusted to one end of the lever 76 during the return process point of the limited range of adjustability results. The spring 90 is deliberately weakly reached, which is available to the user, so that it prevents the actuation of the bimetallic device Current tripping and the movement of the lever 76 in the six and ten times the nominal current of the clockwise direction during the return process is a switch. In this way, in the case of severe, briefly negligible resistance is opposed. In conclusion, an instantaneous triggering of the switch causes the ambient temperature to compensate for. A response to normal motor-on bimetal element 84 is combined with a component 96 made of insulating currents and similar short-term overloading material, which, however, is likewise not a good thermal one. The magnetic overcurrent mixer is an isolator. In this component 96, the release device can be attached to any current strength within pivot bearing 86. An approach 96 a is available with a wide range, for example between 250 effective ends of the bimetallic strip 32 at a 4 ° and 2500A can be set. When the stop is engaged, it is raised relatively far from the 104 to a position in which the gap is located at the end of the bimetallic strip 32 secured between the anchor 98 and the core 106 by means of the screw 30. In addition, one is enlarged, the line of attack of the spring extension 96 & on the component 96 is provided, which is changed above 102 so that the component of the spring rests within the right extension of an armature 98, the tension is increased, which the Armature 98 of sen pivot 100 is mounted in frame 74. Which pulls off the core 106. These factors result in armature 98 being jointly pretensioned in the clockwise direction by a spring 102 over a particularly wide adjustment range. A movement of the armature 98 clockwise. The triggering of the switch in the event of an overload is clockwise caused by an adjustable stop through the bimetallic strip 32, which is limited to 104 . The spring 102 is deflected at its right 5 ° base of the heating of the bracket 26 upwards at a part of the adjustable stop 104 . Such a deflection shifts the fastened. The armature 98 is arranged above the conductor 26 bimetal element 84 in a clockwise direction about the pivot and between the side arms of a bearing 86 and triggers the switch. The close-fitting U-shaped magnetic core 106 , which is inserted into the base part 12 in other lying bimetallic strips 32 and bracket 26 and extends around three 55 enables the heat that extends in the sides of bracket 26 to be used. When the bracket 26 conducts current through current-carrying conductors, a magnetic field is generated in the core. Thus, no carefully manufactured 106 has been produced which attracts the armature 98 in the direction of the U-shaped resistors for heating the bimetallic element 84. If this current required a bimetal strip. If such a switch has a sufficiently high value, the armature 60 has a rated current of 225 A, while previously 98, and the air gap between the armature 98 and the rated currents of similar comparable switches with the core 106 is reduced, whereby the actuators have the same dimensions only about 100 A are generated force on the armature is increased. Have the pen. The elimination of the separate heater 102 which engages along a line which runs near the device and the flat arrangement of the current sensing line between the pivot 100 and the 65 borrowed bimetallic strip on the bracket 26 leaves a gripping point of the spring on the armature 98 Achieve a compact arrangement, with only a slightly increased tensile stress. The bimetallic strip 32 operates at a lower level - the armature begins to operate at a lower trigger temperature than before. Hence this is

Switches particularly sensitive to changes in ambient temperature. For this Basically, an effective compensation device for the ambient temperature is important. That is the ambient temperature compensating bimetal element 84 is removed from the bimetal strip 32 and from the Arranged by the current heated bracket 26. The strongly expanding side of the bimetal element 85 is on the right in FIG. 2 provided so that increases in the ambient temperature, which would cause the bimetal strip 32 to bend upward, a deflection of the bimetal element 84 to the left and the trigger point is held.

In a series production, it is desirable that the same bimetal strip 32 for a larger one Current range is usable. To achieve this, the shape of the bracket 26, which is in is in the immediate vicinity of the screw 30, can be modified so that the same temperature rise for a switch of 75 A and one for 225 A the same design results by adding the The shape of the bracket 26 is modified, e.g. B. the bracket 26 receives recesses, as shown in F i g. 3 shown is. Although the bracket 26 'in FIG. 3 has recesses 26 a, the current runs through the switch by and large considered practically in a straight line (Fig · 1) · The mechanical load capacity of the bracket 26 against deflection forces of a wire at the terminal 16 becomes independent ensured by the shape of the bracket 26 'in the vicinity of the screw 30 by screws 28. Local heating can also be achieved by reducing the cross section of the bracket 26 in the area of the Screw 30 are generated. In the embodiment shown, the width of the bimetal strip 32 can be effectively heated when the bracket 26 is so wide that it extends along the extends all the way over the bimetal strip; this is the same when using the bracket 26 ' as in the case of bracket 26, which is used for the switch with the highest load in the series. The switch is triggered due to a slight overload when the heating of the Bracket 26 or bracket 26 'results in sufficient heating of the bimetallic strip 32. After a Release causes the spring lever 76 to rotate the common release bracket 62 clockwise, so that the roller 64 moves to the right, the latched end of the latching lever 48 releases and then the contacts are automatically and immediately opened. The latching lever 48 exercises relatively strong upward pressure on roller 64 when latched. This is going through the tension of the four powerful springs 58 causes the contacts to snap into place when opening or Close surrender. The latching lever 48 is held back against the strong spring pressure while The thermal and magnetic current-sensitive device triggers at the same time results. The springs 78 for biasing the relevant spring lever 76 can be much weaker be carried out than before, because a significantly lower force is required to the release lever to rotate when the roller 64 is triggered. The reduction in the force exerted by the springs 78 against the corresponding spring lever 76 is exerted is advantageous in several respects. Most of all will the frictional force at the latch point between each spring lever 76 and the relevant one Screw 82 of the bimetal element 84 is considerably reduced. As a result, a much smaller operating force is sufficient of the bimetal strip 32 to trigger the switch in response to a To achieve overload. Furthermore, the lower strength of the springs 78 and the lower friction at the latching point 76, 82 improves the magnetic trigger sensitivity.

A reduction in the strength of the springs 78 has the advantage that when the latching lever is returned by moving clockwise with the help of the handle 60 which is on the latter force to be exerted is much lower.

The current path running in a straight line through the switch for its thermal release is in the Advantageous with regard to the protection of branch circuits if the supply line carries high currents. Electrodynamic loads can be based on the straight through the switch Avoid stirrups.

Claims (4)

Patent claims: 1.Electric toggle switch with thermal and magnetic overcurrent release, its contacts in the on position via a knee joint from a latching lever are held, which is locked by a disengageable stop of the release device is, characterized in that the overcurrent release device (50) is a movable Bearing member (66) and one between the latching lever (48) and the bearing member (66) arranged Has roller (64), the two parts on opposite sides of the roller in rolling Contact is made, and that the current-sensitive device (32, 98, 96, 84, 82, 78, 76) when responding, the bearing member (66) moves so that the roller (64) on the bearing member (48) and latch lever (66) unrolls with virtually no friction and trips the switch. 2. circuit breaker according to claim 1, wherein the current-sensitive device is a bimetallic strip has, characterized in that the bimetallic strip (32) along one current-carrying bracket (26) extends and that between one end of the bimetal strip (32) there is good heat transfer to the bracket (26) and that the overcurrent release already occurs at a relatively small increase in temperature of the bracket (26) takes place. 3. Automatic switch according to claims 1 or 2, characterized in that the overcurrent release device (50) has a pivotable armature (98) which is biased away from its magnetic core (106) by a spring (102), that the line of application of the force exerted by the spring runs close to the axis of rotation of the armature, and that a common device (104, 108, 110, 112, 114, 116) is provided by that of the magnetic gap distance (98 to 106) and the position of the farther away from the armature The end of the spring are adjustable so that the line of attack of the spring is relative to the axis of rotation of the Armature is moved, with these settings at the same time the magnetic trigger sensitivity of the switch increase or decrease. 4. Circuit breaker according to claim 2, characterized in that the overcurrent release device (50) has a pivotable bimetal strip (84) for room temperature compensation, which is actuated by the bimetal strip (32) and extends substantially at right angles to the current-carrying bracket (26). 10 Considered publications: German patent specifications No. 962 998, 962 001, 341,603,337; German interpretation L17981 Vmb / 21c, (announced on June 7, 1956); U.S. Patent Nos. 2,900,473, 2,795,670, 574 093. 1 sheet of drawings