SU875499A1 - Limit switch - Google Patents

Description

(54) WAY TO TURN OFF.

one

The invention relates to electrical equipment of various machines and mechanisms, in particular, to devices for determining the position of mobile mechanisms and signaling their approach to objects.

Travel switches are known for operating with reversible retaining lugs with latching contact state after actuation, consisting of a housing inside which there are kinematically connected contacts with a lever, a roller fixed by the stop 1 is attached to the free end of the lever.

The disadvantage of this switch is the need to fine-tune the stops, which in some cases is difficult to accomplish, especially in lifting equipment.

Closest to the present invention is a limit switch comprising a sealed housing, inside of which there is a movable permanent magnet and magnetically controlled contacts, installed so that they operate in the extreme positions of the movable permanent magnet, and the source

control MDS installed with the ability to move outside the sealed enclosure of the hull.

The disadvantages of the known switch are high reliability due to the presence of rubbing surfaces between the permanent magnet and the housing, which does not exclude jamming of the magnet, the lack of smoothness of its movement, the possibility of the magnet spalking from hitting it with a magnet-like lid; He can work in DC-only circuits. In addition, the switch is structurally folded due to the presence of a U-shaped magnetic circuit, two coils, two lids of a magnet of soft material.

IS

The purpose of the invention is to increase the reliability of work.

The goal is achieved by the fact that in poo. a switch that contains a body of non-magnetic material, inside which is located

Claims (2)

20, a movable permanent magnet and magnetically controlled contacts, installed so that they operate in the extreme positions of the movable permanent magnet, and the control source MDS, are inserted into the switching arm that is located in a housing of nonmagnetic material so that the end is fixed on the axis with the possibility of rotational motion, and the specified permanent magnet is mounted at the other end of the tersky lever, and the direction of the magnetic fluxes from the movable permanent magnet and the control source th IBC match. In such a limit switch, the center of solid of the rocker lever can be located above its axis of rotation. FIG. Figure 1 shows the design of the limit switch with the rails removed; in fig. 2, section A-A in FIG. one; in fig. 3 - position of the movable permanent magnet and the source of the control MDS. The limit switch contains a housing 1 made of a non-magnetic material, inside of which a flip lever 3 is hinged on the axis 2. At the free end of the lever there is a movable permanent magnet 4 that interacts with the magnetically controlled contacts 5. The source 6 of the control MDS is in the form of a constant the magnet is not mechanically connected to the switch body. Both magnets are set according to the magnetic flux. In the extreme position of the lever, a mobile permanent magnet mounted on it pushes out from the poles to the magnetic control contact and creates a magnetic field sufficient to trigger it. The shape of the hull pulley and the location of the center of the body of the rocker arm above its axis of rotation ensure reliable fixation of the arm in the extreme positions. The limit switch works as follows. When the magnet 6 moves, it interacts with the magnet 4 and transfers it from the right position to the left, while the right magnetic contact opens and the left contact closes. Upon further movement of the magnet 6 to the left, the lever remains in the left position and is held there by the force of gravity. When reverse movement of the magnet 6, the lever is transferred to the right position, magnetically. the contacts are switched at this time, and the lever is held in the right position due to gravity. Placing a permanent magnet at the free end of a flip lever, hinged inside the case, reduces friction when it is moved, eliminates jamming, thereby increasing the reliability of operation. The consonant inclusion of magnets in the flow ensures smooth switching, eliminating shocks, the possibility of magnets destruction and also increases the reliability of operation. The implementation of the permanent magnet control element greatly simplifies the design of the limit switch and expands the range of application of the limit switch — it can be used in both DC and AC drive circuits. Claim 1. Instructional switch comprising a body of non-magnetic material inside which there is a movable permanent magnet and magnetically controlled contacts, installed so that they operate in the extreme positions of the movable permanent magnet, and a controllable MDS source outside the housing of a non-magnetic material, characterized in that, in order to increase the reliability of operation, a movable rocker lever is inserted into it, which is located in the housing of a non-magnetic material so that one end is fixed on the axis with the possibility of rotational motion, and at the other end of the transfer lever a specified permanent magnet is mounted, and the magnetic fluxes from the movable permanent magnet and the source of the control MDS are aligned. 2. The switch, according to claim 1, that is, that the center of gravity of the rocker lever is located above its axis of rotation. Sources of information taken into account during the examination 1.Informlectro catalog 07.11.15-76. Switch series VK 200B. 2. USSR author's certificate number 535616, cl. H 01 H 36/00, 1976. ld / ////////. 6 ig.2