DE1061419B - Electromagnetic contactor with overcurrent release - Google Patents

Description

The invention relates to electromagnetic contactors with a pair of opening contacts that lie in the circuit of the main control coil of the contactor and which occur in the event of overcurrents or break the contact between you by pressing the associated push button and through the Push button can be returned to their old position. The invention relates to improvements such contactors with the aim of making it impossible to trigger the electromagnetic Contactor is prevented by the effects of the reset mechanism.

The invention consists in that a device for locking the second of the switch-off contacts in a position in which it is in contact with the first switch-off contact, it is provided that Furthermore, devices are provided for unlocking the second contact in the event of overcurrents are, when triggered, the second contact separates from the first contact and the main control coil turns off that there is also a push-button-operated, reciprocating member, that when moving towards the contacts if the second contact is in the unlocked position is moved both contacts with the second contact returned to its locked position and the first contact is moved so that it remains separate from the second contact and that with his Returning to the opposite position releases the first contact from contact with the second contact, if this is in its blocking position, as long as the device as a result of overcurrents releases the second contact, despite movement of the pressure member in the direction of the contacts to which Switch-off contacts cannot be kept closed.

The invention is described in detail with reference to the figures, which a contactor according to Illustrate the invention with a trigger arrangement of the type basically described above, for example. From the figures is

Fig. 1 is a plan view of the contactor;

Fig. 2 is a side view of the contactor viewed from the right of Fig. 1;

Fig. 3 is a side view of the contactor as seen from the left of Fig. 1;

Figure 4 is a view of part of Figure 2 with some of the parts in different positions with respect to one another are shown;

Fig. 5 is a view similar to Fig. 4 and shows the relevant parts in yet another position with respect to one another;

Fig. 6 is a partial side view of another embodiment;

Electromagnetic contactor
with overcurrent release

Applicant:
Allen West and Company Limited,
Brighton, Sussex (UK)

Representative: Dipl.-Ing. RH Bahr, patent attorney,
Herne (Westphalia), Freiligrathstr. 19th

Claimed priority:
Great Britain April 1, 1952

Frederick James Pavitt
and Albert William James Berry, Brighton, Sussex
(Great Britain),
have been named as inventors

FIG. 7 is a view corresponding to FIG. 6 and shows the parts in a different position relative to one another.

The three-phase contactor shown in FIGS. 1 to 3 has a main control coil 1 and three bridge contacts 2 which, when the coil pairs are excited, connect fixed contacts 3 in the relevant phases to one another.

In the circuit of the main control coil 1 are a pair of starting contacts 4 and 5, which are closed by depressing a starting pushbutton 6 , and in shunt with these normally open starting contacts 4 and 5, a fourth fixed contact 7, which is connected to a bridge contact 8 when the main control coil is energized 1 is connected.

By pressing the start button 6 , the main control coil 1 is energized, and all four bridge contacts 2, 2, 2, 8 connect the fixed contacts 3, 3, 3, 7 assigned to them, the fourth bridge contact being the normally open starting contacts 4 and 5 in a known manner bridged and causes a self-holding of the contactor, so that the push button 6 can be released.

Furthermore, a pair of normally closed switch-off contacts 9 and 10 are located in the circuit of the main control coil. These contacts are opened, as will be described in detail later, by pressing down a switch-off pushbutton 11 . This de-energizes the main control coil, the three phases and the shunt 7, 8

909 577/325

the starting contacts 4, 5 are interrupted, so that when the switch-off button 11 is released and consequently Closing the switch-off contacts 9 and 10 again, the main control coil 1 is not re-energized, instead, it is necessary to press the starter button 6 down again for this purpose.

Overcurrent coils 12 are connected in the three phases. These are with overload protection devices equipped in the form of magnet armatures 13, which are raised when overloaded. Furthermore is a common trip rod 14 is provided, which is arranged across the heads of the armature and is also raised by lifting one or more of the armature. This will be the switch-off contacts 9, 10 open with a snapping effect. To the switch-off contacts 9 and 10 To close again, the switch-off push button 11 must be depressed and released, as before will be described.

The switch-off contact 9 consists of a lamella arranged to the right of the release rod 14, at at 15 is articulated near its upper end on an axis parallel to the trip bar and usually is perpendicular, but can give way to the right to on their articulation axis against a spring tension.

The other switch-off contact 10 is formed by an approach of a locking member that consists of one articulated near its lower end on an axis 17 lying parallel to the release rod 14 There is arm 16 which extends upwards from this axis and almost immediately below the release rod ends. The breaker contact 10 consists of a locking member to the right of this slightly above the pivot axis 17 protruding approach. So if the locking member is pivoted to the right and left about the pivot axis 17, the switch-off contact 10, if special measures were not taken, only alternately to the installation on the switch-off contact 9 arrive or be separated from this. When the locking member with its upper end is pivoted to the right, it slides if the release rod 14 is in its normal lower position is located below the release rod, and this prevents, as can be seen from Fig. 2, its return movement and thus holds it in the position in which the two switch-off contacts 10 and 9 are in engagement with one another stand. The locking member is under the action of a spring 34, which is to be described in Way endeavors to push it to the left.

The locking member is activated by the switch-off push button 11 via an intermediate arrangement actuated. This consists of a member 18 that can be moved back and forth in the horizontal direction moves left and right (i.e., perpendicular to the trip bar). The link 18 is in a Lost motion connection with the locking member 16 with contact 10, so that as soon as it moves to the right, the locking member is pivoted to the right and then freely to a certain distance can move back to the left, the locking member being retained by the release rod 14.

This lost motion connection is approximately at the level of the extension that forms the switch-off contact 10. That in the horizontal direction back and forth movable member 18 also carries on one extending from it Arm 19 an insulating roller 20 which lies in a plane above the switch-off contact 10. the The arrangement here is such that when the member 18 reciprocable in the horizontal direction is moved

moved to the right, this role in front of the switch-off contact 10 to act on the switch-off contact 9 arrives.

In operation, the locking member 16, 10 held sufficiently far to the right by the release rod 14 so that the switch-off contact 10 makes contact with the switch-off contact 9. The in the horizontal direction reciprocable member 18, on the in no pressure is exerted in any direction, assumes a loose position in which the insulating roller 20 either is out of engagement with the switch-off contact 9 or only loosely touches it.

To close the switch, the switch-on pushbutton 6 is briefly depressed and the main control coil 1 excited as described. After closing the switch, the in Fig. 2 shown position of the organs to each other.

If now the contactor is to be opened, the switch-off push button 11 is pressed. Through this the horizontally reciprocable member 18 is moved to the right and brings the insulating Roller 20 to rest on the switch-off contact 9, which is also out of engagement with the right the switch-off contact 10 is brought, as shown in FIG. This is done before the lost motion connection of the member movable in the horizontal direction with the locking member 16, 10 effective will. This interrupts the circuit of the main control coil 1 of the switch and the Switch open. As soon as the switch-off pushbutton 11 is released, the switch-off contact 9 can again return to the position in which he makes contact with the switch-off tkontakt 10, and the switch is ready again for a renewed closing or switch-on process by pressing down the switch-on pushbutton 6th

If the switch is closed and an overcurrent occurs, the release rod 14 is raised after a delay, which is determined by the brake cylinder 12 a , the locking member 16, 10 moves as a result of the acting spring force in its extreme left position, as in Fig. 5 shown, and the switch-off contact 10 is free before the switch-off contact 9. As a result, the main control coil 1 is de-energized and the switch opens. The locking member 16, 10 also holds the member 18, which can move back and forth in the horizontal direction, in its left end position, and the insulating roller 20 is out of contact with the switch-off contact 9.

In order to close the switch-off contact 10 again, the switch-off pushbutton 11 must be pressed briefly will. As a result, the member 18, which can be reciprocated in the horizontal direction, is moved to the right and in turn moves the locking member 16, 10 to the right. During this movement comes the insulating roller 20 in front of the switch-off contact 10 for contact with the switch-off contact 9, and the switch-off contact 9 is, constantly leading the switch-off contact 10, pushed to the right, so that no contact between these two takes place. The upper end of the arm 16 of the locking member slides on here the right side of the trip bar 14.

When the switch-off pushbutton 11 is released, the switch-off contact 9 returns to the position after back to the left and take the insulating roller and the one that can be moved back and forth in the horizontal direction Link 18 with it until it comes to rest on the switch-off contact 10, which is now activated by the release rod 14 is held back. The contacts are closed,

I 061

and the organs are in the position shown in Fig. 2, in which the contactor by pressing the Switch-on push button 6 can be closed again.

If, while an overcurrent occurs, someone puts their finger on the switch-off pushbutton 11, However, without exerting a pressure which would be sufficient to separate the switch-off contacts 9 and 10 from one another disconnect, this cannot prevent the contacts from opening and the switch being triggered. How out the description of the reset process emerges, the locking member 16, 10, as a result of the in this arranged slot in which the pin 37 of the member 18 sits, is always under the spring action move to the left as soon as the trigger rod 14 is raised. Establishing contact between the switch-off contacts 9 and 10 is always prevented by the insulating roller 20. One contact between the switch-off contacts 9 and 10 can only take place when the release rod 14 is the locking member 16, 10 holds back.

FIGS. 6 and 7 illustrate a modified embodiment in which the switch-off contacts 9 and 10 are automatically closed again and in which the locking member 16, 10 also automatically returns to its original position after the occurrence of an overcurrent. With this arrangement an existing insulating angle lever 21 is provided around a parallel to the trigger rod 14 lying, fixed axis 22 is pivotable and is under the action of a spring 23 which strives to him to pivot in the clockwise direction. Four vertical ones extend from the armature of the coil 1 Pin 24 upwards, the supporting organs for the bridge contacts that are resiliently mounted on them 2, 2, 2, 8 form. The armature is resiliently upward into the open position of the contacts 2, 2, 2, 8 pressed and pulled into the closed position of the contacts when the coil 1 is energized. An arm 25 of the angle lever 21 is approximately horizontal and is by the spring 23 in the direction pressed down against one of the pins 24. However, the strength of the spring 23 is such that it is not enough to push the armature of the coil 1 down when the coil is de-energized, but the Pressure of the spring of the armature prevails in the upward direction, and the pin 24 is raised and the angle lever counter-clockwise against the pressure it is under twisted.

Usually, as shown in Figure 6, the switch is closed and the trip bar 14 is located is in the lower position, since the arm 16 is locked in its right-hand position by the release rod is, the contacts 9 and 10 are pressed against each other. In this position it is almost vertical other arm of the angle lever 21 to the left of the arm 16 at a sufficient distance therefrom. If an overcurrent of sufficiently long duration occurs, the trip rod is raised, the arm 16 is freely pivoted in the counterclockwise direction, so that the contacts 9 and 10, as described above, can be opened.

This is the position of the parts to one another shown in FIG. 7. However, this position is only for one Moment, because as soon as the switch-off contacts 9 and 10 open, the main coil 1 is de-energized and so the armature lifts this coil with the pin 24. This is in addition to the opening of the main switch contacts of the angle

lever 21 pivoted in the counterclockwise direction, and he causes his vertical arm the arm 16 pushes to the right so that it is through the release rod, which after opening the main switch contact has fallen down again, is locked again in the position shown in FIG. 6, the Switch-off contacts 9 and 10 are closed again.

In both embodiments described, the structure of the contactor including the Switch-on contacts 4, 5, the Folding contacts 7, 8 and the overcurrent coils 12 and the armature 13 of the usual, so that no detailed description of this arrangement is necessary. Some special design features the switch-off and reset mechanism consist in that the trip rod 14 consists of one Piece of strong wire is formed, which lies over and on the anchors 13 and whose end portions 14 a are bent at right angles so that the ends 14 & in turn are bent inwards again and into holes are pivotably mounted in a fixed part of the construction.

The pivotable arrangement of the switch-off contact 9 is created in that its upper part 26 bent to a U-shaped cross-section and its concave side by means of a spring 27 against the edge of a plate 28 attached to the fixed part of the structure is pressed. At the pivot point 15, this plate 28 has a shoulder extension, not shown, so that the contact 9 pivoted to the right by pressure on its lower end around the angled point of this shoulder approach and the spring 27 is compressed. The spring 27 is wound on an arm that with the plate 28 is made in one piece and passes through a hole in the part 26 of U-shaped cross-section extends and clamped between this part and a disc 30 arranged on the arm.

The locking member 16, 10 consists of a flat, stamped plate of suitable shape by means of a pivot pin

17 with a fixed vertical plate 31, which in turn is attached to a fixed part of the structure is, is pivotably connected. To the locking member, as can be seen from the figures, To put it under a pressure acting in the counterclockwise direction, it is with a tail-shaped one Approach 32 provided, and the plate 31 has a triangular extension 33 on which the Spring 34 is seated. When the locking member is rotated in the clockwise direction, the presses Approach 32, the spring 34, as can be clearly seen from the figures, together.

The member 18, which can be reciprocated in the horizontal direction, exists together with the arm 19 from a one-piece plate, the end of which is bent at 35 so that a stop is formed, against which the push button 11 can come to rest. The end of the fixed plate 31 is (Fig. 1) at 36 bent, and the back and forth in the horizontal direction member 18 is by a Slot in the bent part of the plate 31 and a transverse pin 37, which is fixed to it and is in a horizontal slot 38 of the plate 31 moved, guided. The lost motion connection between the in horizontal direction reciprocable limb

18 and the locking member 16 is formed by this pin 37, which is also in a not shown Slot engages in the plate forming the locking member. The parts are through

Claims (7)

a head 39 held together on the pin 37. The switch-off push button 11 is arranged in the wall of the switch housing. It is pressed outward by a spring 40. As soon as the push button is pressed inwards against the tension of this spring, its shaft 41 comes into engagement with the bent end 35 of the link 18 and pushes it to the right. Pa t ext a ns h k (■ ciie. 1. Electromagnetic contactor with a pair of switch-off contacts, which are in the circuit of the main control coil of the contactor and which interrupt the contact between them in the event of overcurrents or by pressing the associated push button and can be brought back into their old position by the push button in that a device (14) is provided for locking the second of the disconnecting contacts (10) in a position in which this is the first break contact (9) is in contact, that further comprises means for unlocking the second contact (10) when Occurrence of overcurrents are provided, when triggered, the second contact (10) is different from the first contact (9) separates and the main control coil (1) switches off, that a pushbutton-operated, reciprocating member (18) is also present, which when the second contact is unlocked when it moves in the direction of the contacts (9, 10) Position, both contacts are moved, the second contact (10) being returned to its locked position and the first contact (9) being moved so that it remains separated from the second contact (10) and that on its return to the opposite position the first contact (9) releases the contact with the second contact (10) if this is in its blocking position, whereby as long as the device (14 ) releases the second contact (10) due to the occurrence of overflows, despite movement of the pressure member (18 ) in the direction of the contacts, the switch-off contacts (9, 10) cannot be kept closed. 2. Electromagnetic contactor according to claim 1, characterized in that the second contact (10) is connected to a lever (16) from the release rod (14) is locked, which releases it in the event of an overcurrent in the circuit of the main contacts (2, 3) , and that the pressure member (18) connects the first contact (9) to a part (20) located on this member (18) and moves the second contact (10) with the lever (16) attached thereto via a lost motion connection. 3. Electromagnetic contactor according to claim 2, characterized in that the part (20 ) attached to the pressure member (18) is a frictionless wheel, electrically insulated from the second contact (10) , and the lost motion connection consists of a pin-and-slot connection (37 , 38, 39) . 4. Electromagnetic contactor according to claim 2, characterized in that the second contact (10) with the lever (16) attached to it is rotatably mounted relative to a fixed part (31) and that the pin (37) forming part of the lost motion connection with is attached to the pressure member (18) and engages in a slot in the lever (16) and the second contact (10) and in a guide slot (38) of the fixed part (31). 5. Electromagnetic contactor according to claim 1, characterized in that in a known manner by the control coil (1) actuated holding contacts (7, 8) are provided, which are in series with the switch-off contacts (9, 10) , and that a pair of normally open manually operated switch-on contacts (4, 5) is shunted with the holding contacts (7, 8) . 6. Electromagnetic contactor according to claims 1 to 5, characterized in that the second contact (10) is automatically returned to the locked position after its unlocking due to the occurrence of overcurrents. 7. Electromagnetic contactor according to claim 6, characterized in that the automatic return of the second contact into the locked position is effected by a mechanical device consisting of an angle lever (21) , one arm (25) of which engages the movable magnet armature (24) of the electromagnetic contactor is and its other vertical arm brings the second contact (10) back into its blocking position. 1 sheet of drawings © 909 577/326 7.