JPH0453060B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a contact switching mechanism for an electromagnetic relay.

[Conventional technology]

Conventionally, the contact opening/closing mechanism of this type of electromagnetic relay is
As shown in FIGS. 7A to 7C, it has fixed contacts 36 and 37 facing each other, and movable contacts 38 and 39 that are fixed at one end and opposite to the fixed contacts 36 and 37 at the other end. It consists of one movable contact spring 32 to which preliminary pressure is applied on the 36 side, and a stud 13. Stud 13
is connected to a movable block etc. that moves by an excitation circuit formed by an iron core around which a coil is wound and a yoke magnetically connected to this iron core, and moves with the movement of this movable block etc. When the stud 13 is in the position shown in FIG. 7A, the stud 13 is not in contact with the movable contact spring 32, and due to the preliminary pressure of the movable contact spring 32, the fixed contact 36 and the movable contact 38 are opened, and the fixed contact 37 is opened. The movable contact 39 is in an open state. When the movable block is moved by the excitation of the iron core placed near the movable contact spring 32, the stud 13 moves as shown by the arrow in FIG. 7B and presses the movable contact spring 32, causing the fixed contact 36 and the movable contact to 38 is open. Further movement of the stud 13 closes the fixed contact 37 and the movable contact 39, as shown in FIG. 7C, thereby switching the contacts.

[Problem that the invention seeks to solve]

In recent years, there has been a demand for compact electromagnetic relays that are highly sensitive and have a high dielectric strength between contacts, but the contact switching mechanisms of the conventional electromagnetic relays described above have the following drawbacks.

(1) To increase the voltage resistance between opposing contacts, it is necessary to increase the contact gap.In order to increase the contact gap without changing the stiffness of the movable contact spring,
As shown in Fig. 8, △c (contact gap) ≒ d (stud ~ displacement) - α ₁ (movable contact spring deflection) -
Depending on the relationship between α ₂ (movable contact spring play amount), it is necessary to increase the stud displacement amount d or to select a small movable contact spring deflection amount α ₁ and play amount α ₂ . Here, reducing the movable contact spring deflection amount α ₁ and the play amount α ₂ has limitations in the structure and manufacturing of the electromagnetic relay, so the result is to increase the stud displacement amount d. On the other hand, from the relationship between the stud displacement amount d and the magnetic class attractive force F (force applied to the stud) shown in Figures 9A and 9B, the excitation is expressed by the area sandwiched between the rated excitation curve Fa and the de-excitation curve Fb. Assuming that the energy S is constant, as the stud displacement amount d increases (α ₁ > d ₂ ), the interval △F between the rated excitation curve Fa and the de-excitation curve Fb becomes smaller, and the spring load curve (not shown) becomes smaller with the interval △
Since it is no longer within F, matching becomes difficult and the sensitivity of the electromagnetic relay decreases. On the other hand, if the stud displacement amount d is made small, the sensitivity of the electromagnetic relay can be increased, but the withstand voltage between the contacts will be reduced.

(2) As shown in Figures 7A to 7C, movable contacts 38 and 39 are connected between fixed contacts 36 and 37.
Since one movable contact spring 32 is arranged, after the stud 13 presses the movable contact spring 32 and the fixed contact 36 and the movable contact 38 are separated, the fixed contact 37 and the movable contact 39 come into contact with each other. Although a contact can be constructed, a continuous contact in which the fixed contact 37 and the movable contact 39 are brought into contact and then the fixed contact 36 and the movable contact 38 are separated cannot be constructed.

[Means for solving problems]

The contact opening/closing mechanism of the electromagnetic relay of the present invention includes two movable contact springs each having one end fixed and a movable contact at each other end; a set of fixed contacts disposed; and a stud disposed between and outside the two movable contact springs; movement of the stud opens and closes the movable contact of the movable contact spring and the fixed contact; The stud disposed between the contact springs is characterized in that it has a configuration in which it contacts one of the two movable contact springs, but does not contact the other at all.

〔Example〕

Next, the present invention will be explained with reference to the drawings.
Referring to FIGS. 1A-1C, one embodiment of the present invention includes two movable contact springs 68 and 69 having one fixed end of each and movable contacts 681 and 691 at the other end thereof; Contact 68
Fixed contacts 721 and 731 arranged to face each other, and movable contact spring 68
and 69 and on the outside of the stud 52.
1,522,523. Movable contact spring 6
8 has a preliminary pressure on the fixed contact 721 side. The studs 521, 522, 523 are arranged without changing their relative positions and are connected to a movable block which is moved by an electromagnetic block which will be described in detail later. The studs 521, 522, and 523 are held down in the direction of arrow A by magnetic attraction F, and as shown in FIG. Then, the stud 521 presses the movable contact spring and the movable contact 681 and the fixed contact 721
is open. Here studs 521, 52
2,523 moves in the direction of arrow B under magnetic attraction F, stud 523 presses movable contact spring 69, and movable contact 691 and fixed contact 731 open (FIG. 1B). When the pressure on the stud 521 is released, the movable contact 681 and the fixed contact 721 are closed due to the preliminary pressure of the movable contact spring 68 (FIG. 1C), and the contacts are switched. In this way, the transfer contact is configured. As is clear from Fig. 2, the contact gap △c in the same embodiment
is the stud displacement amount d, the movable contact spring play amount α ₂ ,
From the amount of springing of the movable contact spring α ₃ , △c≒d−α ₂ +
α ₃ , and compared to the conventional contact opening/closing mechanism shown in FIG. 8, even if the stud displacement amount d is the same, the contact gap can be increased by the movable contact spring deflection amount α ₁ + the movable contact spring springing amount α ₃ , Therefore, it is possible to realize a contact opening/closing mechanism for an electromagnetic relay that has a higher voltage resistance between the contacts than the conventional one without lowering the sensitivity.

Next, a structural example of an electromagnetic relay using the first embodiment of the present invention will be described. Referring to FIG. 3, such electromagnetic relays each have a first end 5a.
A movable block 4 in which U-shaped magnetic pole plates 5 and 6 having second ends 5b and 6a are fixed to both magnetic poles of a permanent magnet 7; a card 51 holding this movable block 4; Iron core 1 in which portion 1a is arranged between magnetic pole plate end portions 5a and 6a
A yoke 2 which is magnetically connected to the iron core 1 and whose end portion 2a is arranged opposite to the outside of the magnetic pole plate end portion 5b, a coil spool 21 that winds the coil 3 and guides the card 51, and a It is composed of an insulating base 60 having movable contact springs 62, 63, 68, and 69 that are driven, and a cover 40 that covers this insulating base 60.

A movable block 4 composed of a permanent magnet 7 and two U-shaped magnetic pole plates 5 and 6 is held by a card 51 to constitute a card block 50. A residial plate 5c is attached to the inner surface of the magnetic pole plate 5 to provide a mechanical magnetic gap. The card 51 has a movable block holding part 54, one guide protrusion 53 on the left and right sides, and a movable contact spring drive part 52 with three studs 521, 522, 523 on the left and right sides. Coil spool 2
1 has a flange 23 provided with a guide 27, a flange 25 provided with a coil terminal 36 for drawing out the coil 3, and a hole 22 into which the iron core 1 is fitted. Assemble the yoke 2 to the coil spool 21 from below, and insert the iron core 1 inserted through the hole 22 into the yoke 2.
By driving it into the fitting hole 2C and combining it,
A coil block 20 is constructed. Insulating base 60
is a fitting recess 61 into which the coil block 20 fits.
, fixed contact terminals 66 and 72 arranged on both outsides of this fitting recess 61 , and this fixed contact terminal 66
and fixed contact terminals 67 arranged on both outsides of 72.
and 73, one end of each is arranged between fixed contact terminals 66 and 67 and between 72 and 73, and the other end of each is arranged between neutral terminals 64, 65, 7.
Movable contact springs 62, 63, 6 fixed at 0,71
It has 8,69. Although not shown, the fixed contact terminals 72 and 73 each correspond to the fixed contact 72.
1,731, and the movable contact springs 68, 69 have movable contacts 681, 691.
2 and 68 have preliminary pressure on the fixed contact terminals 66 and 72 side.

A plurality of protrusions 29 at the bottom of the coil spool 21 are fitted into holes in the fitting recess 61 (not shown).
By fitting the coil block 20 into the insulating base 60, the guide protrusion 53 of the card 51 is fitted.
The card block 50 is assembled from above so that it engages with the guide groove 28 formed by the guide 27 of the coil spool 21. The magnetic pole plate ends 5a and 6a of the movable block 4 are arranged opposite to both side surfaces of the iron core end 1a, and the magnetic pole plate end 5b is arranged to face inside the yoke end 2a. card block 50
is loosely supported by a guide 27 so that it can slide and move in parallel in the direction of the magnetic poles of the permanent magnet 7. An electromagnetic relay is constructed by covering the insulating base 60 with the cover 40 (FIG. 4). When the coil 3 is not energized, the card block 50 is attracted toward the yoke end 2a by the magnetic flux of the permanent magnet 7. Magnetic poles are generated at the magnetic pole plate ends 5a, 5b, 6a, and 6b due to the magnetic flux of the permanent magnet 7, and magnetic poles are generated at the iron core end 1a by energization of the coil 3.
The card block 50 is moved in parallel to the opposite side of the yoke end 2a by attraction and repulsion with the magnetic pole excited at the yoke end 2a, and the studs 521 to 523 of the movable contact spring drive section 52 switch the contacts.

FIG. 5 shows the relationship between stud displacement, magnetic attraction force, and spring load force in this electromagnetic relay. The horizontal axis shows the stud displacement amount d, and the vertical axis shows the force F applied to the stud. The broken line Fa shows the rated excitation curve, the solid line Fb shows the de-excitation curve, and the solid line Fc shows the spring load force. Further, the constant chain line Fd is an exciting excitation curve representing the minimum magnetic attraction force required to move the stud and switch the contacts.

FIGS. 6A to 6C show a continuous contact structure according to another embodiment of the present invention. A construction feature that differs from the first embodiment is that it provides a pre-pressure on both movable contact springs 68 and 69, and that the stud 521
This is because the distance between the stud 523 and the stud 523 is widened. The state in which the stud 521 presses the movable contact spring 68 and the movable contact 681 and the fixed contact 721 are separated, and the stud 522 presses the movable contact spring 69 so that the movable contact 691 and the fixed contact 731 are in contact (6th A).
When studs 521 to 523 move in parallel in the direction of arrow B, studs 521 and 522 move toward movable contact springs 68 and 69, respectively.
When the pressure is released, the movable contact 681 and the fixed contact 721 come into contact with each other due to the pre-pressure applied to each, and the movable contact 691 and the fixed contact 731 continue to contact each other (Fig. 6B), and then the stud 523 moves. The movable contact 691 and the fixed contact 731 are separated by pressing the contact spring 69 (FIG. 6C). As described above, a continuous contact is configured in which the movable contact 691 opens after the movable contact 681 closes. A stud 522 is also provided on the movable contact spring 68 side, and the sixth
The movable contact spring 68 may be pressed at the position shown in Figure C.

The above description also applies to the movable contact springs 62 and 63 in FIG. 3. Further, in the figure, the preliminary pressure applied to the movable contact springs 62, 63, 68, and 69 can be adjusted by individually twisting the neutral terminals 64, 65, 70, and 71, which are each fixed independently. .

〔Effect of the invention〕

As explained above, the present invention provides high sensitivity by configuring a contact opening/closing mechanism from two movable springs arranged between fixed contacts facing each other and studs arranged between them and on both outer sides. This has the effect of maintaining high withstand voltage between the contacts. It also has the effect of easily configuring continuous contacts.

[Brief explanation of the drawing]

1A to 1C are plan views showing the first embodiment of the present invention, FIG. 2 is a diagram explaining the characteristics of the same embodiment, and FIGS. 3 and 4 are respectively the first embodiment. FIG. 5 is a diagram showing the characteristics of the stud displacement amount, magnetic attraction force, and spring load force in the electromagnetic relay, and FIG. 6A to FIG. 6C is a plan view showing other embodiments of the present invention, FIGS. 7A to 7C are plan views showing conventional contact opening/closing mechanisms, and FIG. 8 is a diagram illustrating the characteristics of the conventional example. FIGS. 9A and 9B are diagrams showing the characteristics of stud displacement and magnetic attraction force in the conventional example. 1... Iron core, 1a... Iron core end, 2... Yoke, 2a, 2b... Yoke end, 2c... Fitting hole, 3... Coil, 4... Movable block, 5, 6
...Magnetic pole plate, 5a, 5b, 6a, 6b...Magnetic pole plate end, 7...Permanent magnet, 20...Coil block, 21...Coil spool, 22...Hole, 2
3, 25...flange, 26...coil terminal, 27...
...Guide, 28...Guide groove, 29...Protrusion,
50...Card block, 51...Card, 52
...Movable contact spring drive section, 53...Guide protrusion,
521, 522, 523... Stud, 60...
Insulating base, 61... Fitting recess, 62... Movable contact spring, 64, 65, 70, 71... Neutral terminal, 6
6, 67, 72, 73...Fixed contact terminal, 68
1,691...Movable contact, 721,731...Fixed contact.

Claims (1)

[Scope of Claims] 1. Two movable contact springs each having one end fixed and a movable contact at each other end; and a fixed contact disposed opposite to each movable contact of the two movable contact springs. and; a stud disposed between and outside the two movable contact springs; and a contact opening/closing mechanism for an electromagnetic relay that opens and closes the movable contact of the movable contact spring and the fixed contact by movement of the stud, A contact switching mechanism for an electromagnetic relay, characterized in that a stud disposed between the contact springs contacts one of the two movable contact springs but does not contact the other at all.