DE1034252B - Thermal overcurrent relay, in particular protection relay against single-phase operation of motors - Google Patents

Description

The invention relates to a thermal overcurrent relay, in particular a protective relay against Bin-phase operation of motors with one indirectly and one directly acted upon by bimetal elements, on interrupter contacts working slide, which are preferably resilient with each other connected and thus mutually displaceable in such a way that with uniform deflection of all Bimetallic links to interrupt contact require more deflection path of the slide than with one overcurrent associated with phase failure, in which individual bimetal elements and thus the indirectly acted upon Slide is held back.

The invention is based on the task of triggering in single-phase running and triggering thermal overload separately and independently adjustable at a minimum Elements to make. In the arrangements already proposed, the two triggering times are mutually exclusive connected, d. i.e. if the overcurrent tripping has been set to a higher value, then the triggering for single-phase operation was automatically set in such a way that the motor only starts running at one higher current of the live phases was switched off.

Another known embodiment makes separate triggers to avoid this disadvantage Use. The bimetallic strips are not rigid in the housing, but on a second one Fastened slider, which acts on its own trigger element. With this arrangement, the multitude prepares of bearings and flexible supply lines for the bimetal heating possibly significant difficulties. This independence of the two types of attitudes is according to the present invention beli low cost of elements through the use of a Contact bridge reached, which is connected at least positively to the directly acted upon slide is, a rigidly arranged and a preferably force-fit.ig with the indirectly acted upon Slide connected movable fixed contact.

Using three exemplary embodiments shown in the drawing (FIGS. 1 to 3), the overcurrent relay according to the invention and its effect explained below:

The bimetallic strips 4, 5, 6 work together with the two slides 1 and 2, namely the Slide 1 is actuated directly by the bimetal strip when this is in the direction of the Arrows moved when heated. This strip works on a pivot point 3 rotatable double-armed lever with the arms 7 and 8, namely the lever 7 engages directly on the bi-thermal overcurrent relay,

especially protective relays
against single-phase running of motors

Applicant:

Siemens-Schuckertwerke

Corporation,

Berlin and Erlangen,

Erlangen, Werner-von-Siemens-Str. 50

Max Huber, Amberg (Obpf.),
has been named as the inventor

metal strips, while the lever 8 cooperates with a fixed contact 9. The lever 7, however works with the second contact 10, whose position in space depends on the position of the Slide 2 is.

The mode of operation of the overcurrent relay shown is as follows: When the three bimetallic strips 4, 5, 6 are deflected, i.e. when all three phases are loaded, the slide 1 and, via the spring 11, the slide 2 are moved to the left. Thereby, the lever 7 and the lever 8 is pivoted about the pivot point 3, in such a way ¹ until the lever 8 lifts off the contact 9, thus interrupting the circuit. The contact 10, on the other hand, is resiliently mounted and moves after the lever 7 without being lifted from it. In the case of single-phase operation, however, that is to say in the event that at least one bimetal strip remains, the contact 10 is retained by the bridge 12 of the slide 2, and the circuit is interrupted at this point. By setting the bridge 12 and thus the position of the contact 10 or the contact 9, both the tripping time for single-phase operation and for electrical overload can be set completely independently of one another.

Fig. 2 shows a structural modification, with the difference that the contact 10 supporting leaf spring 13 is arranged parallel to the lever 7 of the switching element. This allows a particularly favorable structural shape can be created with little space required.

In Fig. 3 it is shown that the arrangement can already be realized that on the

C09 577,307

Slide 1 a contact bridge 14 is arranged, which once with the contact 10, which in this case is attached directly to the slide 2 and cooperates with a movably arranged contact 9. In this case, too, a setting can be made very simply by using the position of the contacts 9 and 10, and achieve it independently of each other. By the described embodiments are the implementation options of the relay according to the invention are not exhausted. The trigger link can z. B. consist of a one-armed lever on which both contact points and the working slide attack. The compensation strip, which may have to be arranged, would have to work together with the fixed contact.

Claims (5)

Patent claims: 1. Thermal overcurrent relay, especially protective relay against single-phase operation of motors with one indirectly and one directly acted upon by bimetal links on breaker contacts working slide, which is preferably connected to one another in a resilient manner and thus are mutually displaceable in such a way that with uniform deflection of all bimetallic members more deflection of the slide is required to break the contact than one with phase failure connected overcurrent, in which individual bimetal elements and thus the indirectly acted upon Slider is held back, characterized by the use of a contact bridge, which is at least positively connected to the directly acted upon slide, one rigidly arranged and one preferably frictionally engaged with the indirectly acted upon Slide connected movable fixed contact. 2. Overcurrent relay according to claim 1, characterized in that the movable fixed contact arranged directly on the indirectly acted upon slide is. 3. Overcurrent relay according to claim 1, characterized in that the contact bridge as a lever, is preferably designed as a double-armed lever. 4. Overcurrent relay according to claim 1 and 3, characterized in that the movable fixed contact is attached to a leaf spring, which is parallel to the contact bridge designed as a lever is arranged and with an extension in a corresponding recess of the indirectly acted upon The slide engages. 5. overcurrent relay according to claim 1 to 4, characterized in that the fixed contacts in are designed to be adjustable with respect to their rest position. Considered publications:
U.S. Patent No. 2,199,477. 1 sheet of drawings ® 809 577/307 7.58