JP2008147128A - Electromagnetic contactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To aim at reducing power consumption of an electromagnetic contactor, eventually reducing a calorific value. <P>SOLUTION: The electromagnetic contactor is provided with an electromagnetic force grant part 1, a magnetic core 13, a fixed contact 15, and a movable contact 15. The electromagnetic force grant part 1 contains a first and a second electromagnets 11, 12. The first electromagnet 11 generates a first magnetic flux B1. The second electromagnet 12 generates a second magnetic flux B2 which is smaller than that of the first magnetic flux B1. Magnetic force toward the electromagnetic force grant part 1 is granted on the magnetic core 13 by the first and the second magnetic fluxes B1, B2. The magnetic core 13 is movable, and is pulled to the electromagnetic force grant part 1 by the electromagnetic force by the first magnetic flux B1. After the magnetic core 13 is pulled to the electromagnetic force grant part 1, that 1 generates the second magnetic flux B2 which is smaller than that of the first magnetic flux B1. The movable contact 15 contacts to the fixed contact 14 to be linked with the pull of the magnetic core 13 to the electromagnetic force grant part 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic contactor.

  In the conventional electromagnetic contactor, as disclosed in Patent Document 1 shown below, the contact between the movable contact and the fixed contact is controlled only by supplying and interrupting a predetermined power to one electromagnet.

JP 2006-164812 A

  However, according to such an electromagnetic contactor, when the movable contact and the fixed contact are brought into contact with each other, a predetermined amount of power is continuously supplied to one electromagnet, so that a large amount of power is consumed and the amount of generated heat is increased. There was a risk of increase.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to reduce electric power, and thus heat generation.

  An electromagnetic contactor according to a first aspect of the present invention provides a magnetic core (13) and an electromagnetic force directed toward itself to the magnetic core, and generates a first magnetic flux when the magnetic core is attracted to the magnetic core. Is attracted to itself, the electromagnetic force applying part (1) generating a second magnetic flux smaller than the first magnetic flux, the fixed contact (14), and the magnetic core are attracted to the electromagnetic force applying part. In particular, a movable contact (15) that contacts the fixed contact is provided.

  An electromagnetic contactor according to a second aspect of the present invention is the electromagnetic contactor according to the first aspect, wherein the electromagnetic force application unit (1) is a predetermined time from the generation start (t1) of the first magnetic flux. After the elapse of (Δt), the second magnetic flux is generated.

  The electromagnetic contactor according to claim 3 of the present invention is the electromagnetic contactor according to claim 1 or 2, wherein the electromagnetic force application unit (1) generates the first magnetic flux. It has an electromagnet (11) and a second electromagnet (12) that generates the second magnetic flux, and the number of turns of the winding in the second electromagnet is the number of turns of the winding in the first electromagnet. Smaller than.

  The electromagnetic contactor according to claim 4 of the present invention is the electromagnetic contactor according to claim 3, wherein the first electromagnet (11) includes the second electromagnet (12) in itself.

  According to the electromagnetic contactor according to the first aspect of the present invention, the distance between the magnetic core and the electromagnetic force applying unit is reduced by attracting the magnetic core to the electromagnetic force applying unit. Therefore, the magnetic flux for obtaining the electromagnetic force applied to the magnetic core is smaller as the magnetic core approaches the electromagnetic force applying portion. For this reason, by making the second magnetic flux smaller than the first magnetic flux, it is possible to reduce the electric power and, in turn, the amount of heat generation while enabling the contact between the fixed contact and the movable contact.

  According to the electromagnetic contactor according to claim 2 of the present invention, the second magnetic flux is generated before the attracting of the magnetic core is completed by adopting the time required for attracting the magnetic core as the predetermined time. Can be prevented.

  According to the electromagnetic contactor of claim 3 of the present invention, the first magnetic flux depends on the value obtained by dividing the ampere turn in the first electromagnet by the magnetic resistance of the magnetic core when the magnetic core is attracted to the electromagnetic force application unit. To do. The second magnetic flux depends on a value obtained by dividing the ampere turn in the second electromagnet by the magnetic resistance of the magnetic core after the magnetic core is attracted to the electromagnetic force application unit. The smaller the distance between the magnetic core and the electromagnetic force application unit, the smaller the magnetic resistance. However, the number of turns of the winding in the second electromagnet is smaller than the number of turns of the winding in the first electromagnet. Even if the same current is supplied to each of the electromagnet winding and the second electromagnet winding, the second magnetic flux can be made smaller than the first magnetic flux. Therefore, switching from the first magnetic flux to the second magnetic flux can be performed by a simple control of switching the current supplied to the first electromagnet to the second electromagnet.

  According to the electromagnetic contactor according to claim 4 of the present invention, since the second magnetic flux can be generated by using a part of the first electromagnet as the second electromagnet, the electromagnetic force applying unit is downsized. it can.

  1 and 2 illustrate the configuration of an electromagnetic contactor according to the present invention. The electromagnetic contactor includes an electromagnetic force application unit 1, magnetic cores 13 and 131, a fixed contact 14, a movable contact 15, compression springs 31 and 32, and a holder 4. The case where the movable contact 15 and the fixed contact 14 are in contact is shown in FIG. 2, and the case of non-contact is shown in FIG.

  The electromagnetic force application unit 1 includes first and second electromagnets 11 and 12. In FIGS. 1 and 2, the second electromagnet 12 constitutes a part of the first electromagnet 11. That is, the first electromagnet 11 shares a part of the winding of the first electromagnet 11 with the second electromagnet 12. For example, the electromagnetic force application unit 1 may have the first electromagnet 11 and the second electromagnet 12 separately. However, the former is preferable in that the electromagnetic force applying unit 1 can be reduced in size.

  The magnetic force generated by each of the first and second electromagnets 11 and 12 is applied to the magnetic core 13 by an electromagnetic force toward the electromagnetic force applying unit 1. Specifically, the first electromagnet 11 generates a first magnetic flux B1. The second electromagnet 12 generates a second magnetic flux B2 that is smaller than the first magnetic flux B1.

  The magnetic core 13 is movable and is attracted to the electromagnetic force applying unit 1 by the electromagnetic force applied from the electromagnetic force applying unit 1 (FIG. 2). Specifically, when the electromagnetic force application unit 1 generates the first magnetic flux B <b> 1 and applies the electromagnetic force to the magnetic core 13, the magnetic core 13 is attracted to the electromagnetic force application unit 1.

  When the magnetic core 13 is attracted to the electromagnetic force application unit 1, the distance between the magnetic core 13 and the electromagnetic force application unit 1 is reduced. Therefore, the magnetic flux for obtaining the electromagnetic force applied to the magnetic core 13 is smaller as the magnetic core 13 approaches the electromagnetic force applying unit 1. Therefore, after the magnetic core 13 is attracted to the electromagnetic force applying unit 1, the electromagnetic force applying unit 1 generates the second magnetic flux B <b> 2 smaller than the first magnetic flux B <b> 1, and the magnetic core 13 is moved to the electromagnetic force applying unit 1. It can be maintained in the state attracted to 1.

  Since the 2nd magnetic flux B2 can be made smaller than the 1st magnetic flux B1, electric power and also the emitted-heat amount can be reduced in an electromagnetic contactor.

  The magnetic core 131 is fixed and used as a yoke. Specifically, the magnetic core 131 is provided on the side opposite to the magnetic core 13 with respect to the electromagnetic force applying unit 1. By providing the magnetic core 131, a desired amount of magnetic flux can be generated in the electromagnetic force application unit 1 even when the current I flowing through the electromagnetic force application unit 1 is reduced. Therefore, electric power, and hence heat generation, can be reduced in the magnetic contactor.

  The movable contact 15 contacts the fixed contact 14 in association with the magnetic core 13 being attracted to the electromagnetic force application unit 1.

  Specifically, the movable contact 15 is provided on the opposite side of the magnetic core 13 with respect to the fixed contact 14 in the direction d1 in which the magnetic core 13 can move. The movable contact 15 is connected to the magnetic core 13 through the holder 4. That is, when the magnetic core 13 is attracted to the electromagnetic force application unit 1, the movable contact 15 also moves toward the electromagnetic force application unit 1 along the direction d <b> 1 through the holder 4. Therefore, the movable contact 15 contacts the fixed contact 14 from the side opposite to the magnetic core 13 in the direction d1.

  The compression spring 31 is provided between the electromagnetic force application unit 1 and the magnetic core 13. The compression spring 31 returns the magnetic core 31 to the original state (FIG. 1) from the state where the magnetic core 31 is attracted to the electromagnetic force application unit 1 (FIG. 2). Specifically, when the magnetic core 31 is attracted to the electromagnetic force applying unit 1 (position r2), the compression spring 31 is compressed to generate a repulsive force. When the supply of electric power to the electromagnetic force applying unit 1 is cut off, the magnetic core 31 is moved away from the electromagnetic force applying unit 1 by the repulsive force and returns to the original position r1.

  The compression spring 32 is provided on the opposite side of the fixed contact 14 with respect to the movable contact 15, and connects the holder 4 and the movable contact 15. The holder 4 extends from the magnetic core 13 to the side of the movable contact 15 opposite to the fixed contact 14.

  After the movable contact 15 comes into contact with the fixed contact 14, the magnetic spring 13 is further attracted to the electromagnetic force applying unit 1, whereby the compression spring 32 is compressed and generates a repulsive force. The movable contact 15 is pressed toward the fixed contact 14 by the repulsive force. Therefore, a contact failure between the movable contact 15 and the fixed contact 14 is prevented.

  A specific mode of switching between the control for generating the first magnetic flux B1 and the control for generating the second magnetic flux B2 will be described with reference to FIGS. The control part 2 is shown by FIG.1 and FIG.2. The control unit 2 includes a switch 21 and a switching unit 22. The switch 21 includes contacts 211 to 213. The switching unit 22 performs switching between a connection between the contact 211 and the contact 213 (hereinafter referred to as “connection S1”) and a connection between the contact 212 and the contact 213 (hereinafter referred to as “connection S2”).

  Regarding the winding of the first electromagnet 11, one end 11 a is connected to the contact 213 via the power supply 9, and the other end 11 b is connected to the contact 211. As for the winding of the second electromagnet 12, one end 12a is connected to the contact 213 similarly to the one end 11a, and the other end 12b is connected to the contact 212. 1 and 2, the one end 11 a and the one end 12 a are the same and are shared by the first and second electromagnets 11 and 12.

  When the connection S1 is executed by the switch 21 according to a command from the switching unit 22 (FIG. 1), the first electromagnet 11 generates the first magnetic flux B1. When the connection S2 is executed by the switch 21 according to a command from the switching unit 22 (FIG. 2), the second electromagnet 12 generates the second magnetic flux B2.

  FIG. 3 shows a temporal change (b) of the voltage V applied to the electromagnetic force application unit 1 and a temporal change (a) of the current I flowing through the electromagnetic force application unit 1 with the application of the voltage V, respectively. Show.

  The connection S2 by the switching unit 22 is desirably executed after a predetermined time Δt has elapsed (time t2) from the start of execution of the connection S1 (time t1), and is necessary for attracting the magnetic core 13 as the predetermined time Δt. It is particularly desirable to employ time. This is because it is possible to prevent the magnetic core 13 from returning to the original position r1 by executing the connection S2 before the magnetic force applying unit 1 has been attracted to the magnetic core 13.

  The contents described above can be grasped as follows. That is, the electromagnetic force application unit 1 generates the second magnetic flux B2 after a predetermined time Δt has elapsed (time t2) from the generation start (time t1) of the first magnetic flux B1.

  In FIG. 3, the magnetic core 13 returns to the original position r1 at time t3 when the supply of power from the power source 9 to the electromagnetic force applying unit 1 is cut off at time t3.

  In the above-described electromagnetic contactor, it is desirable that the number of turns R2 of the winding in the second electromagnet 12 is smaller than the number of turns R1 of the winding in the first electromagnet 11. The reason will be described below.

  The first magnetic flux B1 depends on a value obtained by dividing the ampere turn in the first electromagnet 11 by the magnetic resistance of the magnetic core 13 when the magnetic core 13 is attracted to the electromagnetic force applying unit 1 as described later. The second magnetic flux B2 depends on a value obtained by dividing the ampere turn in the second electromagnet 12 by the magnetic resistance of the magnetic core 13 after the magnetic core 13 is attracted to the electromagnetic force applying unit 1 as described later.

  The smaller the distance between the magnetic core 13 and the electromagnetic force applying unit 1, the smaller the magnetic resistance. Therefore, the number of turns R1 and the number of turns R1 are substantially the same, and the first and second electromagnets 11 and 12 are wound. If the currents I flowing to each of the two are substantially the same (for example, the current I1 shown in FIG. 3A), the second magnetic flux B2 is larger than the first magnetic flux B1.

  Therefore, by making the number of turns R2 of the winding in the second electromagnet 12 smaller than the number of turns R1 of the winding in the first electromagnet 11, each of the windings of the first and second electromagnets 11 and 12 is set. Even when the same current I is supplied to the second magnetic flux B2, the second magnetic flux B2 can be made smaller than the first magnetic flux B1.

  In addition, switching from the first magnetic flux B1 to the second magnetic flux B2 can be performed by simple control in which the current supplied to the first electromagnet 11 is switched and supplied to the second electromagnet 12.

It is sectional drawing which illustrates the structure of the electromagnetic contactor concerning this invention. It is sectional drawing which illustrates the structure of the electromagnetic contactor concerning this invention. It is a figure which shows each time change of the voltage V applied to (a) electromagnetic contactor, and the electric current I which flows into (b) electromagnetic contactor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic force provision part 11 1st electromagnet 12 2nd electromagnet 13 Magnetic core 14 Fixed contact 15 Movable contact t1 time (DELTA) t Predetermined time

Claims (4)

A magnetic core (13);
When an electromagnetic force directed toward itself is applied to the magnetic core, and the magnetic core is attracted to itself, a first magnetic flux is generated, and after attracting the magnetic core to itself, a second magnetic flux smaller than the first magnetic flux is generated. An electromagnetic force application unit (1) for generating magnetic flux;
A fixed contact (14);
An electromagnetic contactor comprising: a movable contact (15) contacting the fixed contact in association with the magnetic core being attracted to the electromagnetic force application unit.   2. The electromagnetic contactor according to claim 1, wherein the electromagnetic force application unit (1) generates the second magnetic flux after a predetermined time (Δt) has elapsed since the generation start (t <b> 1) of the first magnetic flux. The electromagnetic force application unit (1)
A first electromagnet (11) for generating the first magnetic flux;
A second electromagnet (12) for generating the second magnetic flux,
The electromagnetic contactor according to claim 1 or 2, wherein the number of turns of the winding in the second electromagnet is smaller than the number of turns of the winding in the first electromagnet.   The electromagnetic contactor of claim 3, wherein the first electromagnet (11) includes the second electromagnet (12) in itself.

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