SU849329A1 - Limit switch - Google Patents

Description

(54) TRAVELING SWITCH

one

The invention relates to traveling switches and can be used as an indicator of movements in the automation of robots, forging and pressing, machine-tool industry, river and sea transport.

A displacement detector is known, which contains a fixed permanent magnet located between the excitation winding enclosing the actuator magnetically controlled contacts and the control magnetically controlled contact connected in series with the excitation winding; These magnetically controlled contacts are located in the zone of one pole of the permanent magnet 1.

This device operates in the “on / off” mode and signals one movement.

In automation, the need arises to indicate the difference in time between two movements, i.e. In a number of cases, it is necessary to determine after the completion of the movement of two objects, which of them has moved earlier.

The task can be solved by using two signaling devices, but this requires a circuit for comparing the moments of movement, since in the mentioned signaling devices there is no memorization of the indicator state.

A device for indicating the movement of an "electronic relay containing a magnetic core with measuring windings and two cores one of which is known,

IQ mobile, installed in close proximity to the magnetic circuit. A torsal magnetic circuit with a feedback winding to the collector winding of an oscillator, made on a transistor. The device allows to determine the direction of displacement and the moment of passage of the core, and when two relays are used, the difference in time displacements 2 is determined respectively.

However, the presence of a generator on the transistor reduces the reliability of the device, and

 The use of two relays makes it difficult to solve a technical problem: to determine after the completion of the movement of two objects, which of the two movements occurred earlier.

The closest in technical essence to the proposed device is a limit switch containing magnetic cores with magnetically sensitive sensors mounted on them, two movable magnetic cores, each of which is installed with the possibility of influencing its magnetically sensitive sensor 3.

However, in this switch it is necessary to use several MD.C sources and special signal processing circuits, which considerably complicates the switch. The purpose of the invention is to simplify the design. The goal is achieved by the fact that a movable magnetic core, each of which is installed with the possibility of affecting its own magnetically sensitive sensor, is inserted into a circuit breaker containing magnetic cores with a magnetically sensitive sensor mounted on them, which is installed between these magnetic cores , so that the moving magnetic cores form parallel magnetic circuits with the ends of the magnetic cores in relation to the indicated source of MDS, and, magnetically sensitive tchiki mounted on magnetic circuits on both sides of the source constant MDS. On -fig. 1 shows a two-way t f. L variant of the trip switch; in fig. 2-way track switch; in fig. 3 - the specified path switch. The switch (Fig. 1) contains a magnetic core made of two magnetically soft rods 1 and 2 connected by a permanent magnet 3, and magnetically sensitive sensors 4 and 5 are placed in the section of the magnetic core 1. The controlled movements of two objects are kinematically connected with movable magnetic cores 6 and 7 (kori). In the traveling switch (Fig. 2) the magnetic cores are made of three magnetically soft rods 8-10, between which magnetically sensitive sensors 4 and 5 are placed. The middle core 8 of the magnetic circuit is made T-shaped with its vertical element branching into two parts for clearer separation magnetic fluxes of moving cores 6 and 7. On the middle core 8 of the magnetic circuit, a source MD.C is placed, for example, in the form of a winding 11. The free ends of the magnetic cores 1, 2, -8, 9 and 10 form the poles of the switch. In a simplified version of the indicator (Fig. 3) without special floor sensors, their role is performed by the rods of the magnetic circuit 1 and 2 with the measuring windings 12 and 13 placed on them.

The operation of the switch as an indicator is based on the appearance of magnetic hysteresis and the laws of magnetic circuits. If the poles of the indicator (Fig. 1) are approached by the measles 7 and it closes the circuit with the source of MDS. in the form of a magnet 3, the bark 7 and the portions of the rods 1 and 2 between it and the magnet are magnetized. Obviously, as a result, the difference in magnetic potentials at the poles of magnet 3 decreases, the greater the smaller the magnetic resistance of the resulting magnetic circuit, compared with the internal resistance of the MD.C source, i.e. magnet 3. Thus, in order to more attenuate the difference of magnetic Tents can be used with high internal resistance magnets. Ferrite-barium magnets widely produced now possess this property. When a magnet 6 approaches the indicator and occupies the left part of the circuit, the changes in the magnetic flux in the latter are less because the potential difference of the MD.S source in the contour of this section of the chain. becomes smaller, and the magnetic hysteresis occurrences that prevent the flow between the two parts of the indicator magnetic circuit are evenly distributed. Therefore, the magnetic flux through the sensor field 5 is greater than that through sensor 4, f ™. The permeability of sensor core 5 is less than sensor core 4, TiMfa S 7i i3uuTTip uam RAP n: UHUK-Q nQTuuv i l. which can be easily determined by sending polling pulses to their measuring windings. The indicator works similarly (Fig. 2). The constant supply current of the winding 11 can be turned off after the completion of one of the movements. The indicator action (Fig. 3) is based on the fact that the magnetic core sections covered, for example, by the winding 12, have a smaller compared to the magnetic cores with the windings 13 , the magnetic permeability, if the measles 7 closes the circuit earlier than the measles 6. Therefore, the corresponding information from windings 12 and 13 can be obtained by any known method. Because the magnetization is performed by a constant field, after the completion of the next cycle and the transition in the initial position (i.e., with cores x 6 and 7 removed), all sections of the magnetic circuit (including R, measles) will return to the same initial magnetic state, which would be in the subsequent initial position. This is due to the fact that when Koreas 6 and 7 are removed, the magnetic resistance of both magnetic circuits is very high (as compared to the closed state) and the magnetization of the regions is close to the value of the residual induction on the hysteresis curve. Therefore, each new cycle starts with the same magnetic states of both the left and right parts of the indicator, which ensures the stability and accuracy of its readings. The nearer the closure time of the circuits 6 and 7 of its circuits, the less the signals taken from the sensors 4 and 5 are different, and if these signals are equal, then both the corners 6 and 7 simultaneously touched the rods of the magnetic circuit. Thus, it is possible to judge about the time lag of one displacement relative to another.

The proposed design is distinguished by simplicity and reliability.

Claims (3)

1. USSR author's certificate number 556518, cl. H 01 H 47/00, 1976. 2. Authors certificate of the USSR L1o 259277, cl. H 01 H 47/32, 1966. 3. Author's certificate of the USSR 20 No. 681472, cl. H 01 H 36/00, 1979. with thread-sensitive sensors, two movable magnetic cores, each of which is installed with the possibility of influencing one of the magnetically sensitive sensors, characterized in that, in order to simplify the design, a constant MDS source is inserted into it between these magnetic circuits, so that the movable magnetic cores form parallel magnetic circuits with the ends of the magnetic cores with respect to the indicated source MDS, and f 7 7 four / 1 / 5/37