JPH11204011A - Electromagnetic relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a given creep distance between fixed terminals even of miniaturized so as to ensure a desired insulation properties by providing a groove part between adjacent fixed terminals insert-molded at a base, and forming the given creep distance. SOLUTION: A plurality of first fixed terminals 22 are arranged in parallel at a base 21 by insert-molding, and the first fixed terminals 22 are provided with first fixed contacts 22a, respectively. A groove part 26 is provided between these first fixed terminals 22. Second fixed terminals 32 are mounted to the base 21, and the second fixed terminals 32 are rectangular-shaped, and provided with second fixed contacts 32a. Thus, the groove part 26 is provided, thereby a desired creep distance is formed between the second fixed contacts 32a, there is maintained between the contacts to a desired breakdown voltage, and insulation properties are not inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic relay,
It concerns a very small electromagnetic relay.

[0002]

2. Description of the Related Art Conventionally, in an electromagnetic relay, when a plurality of fixed terminals 2 are integrated with a base 1 as shown in FIG.
The spatial distance X and the creepage distance Y between the fixed terminals 2 are the same. The dielectric constant between the space (air) and the creepage (resin) is greatly different, and the withstand voltage of the creepage is lower than that of the space. In particular, the opening and closing of the contact 2a (movable contact not shown) causes the contact 2
When scattered powder (conductor) is generated from a and adheres to the creeping surface 1a, the withstand voltage is further reduced. For this reason, even if a predetermined spatial distance X is formed between the terminals 2 (or the contact points 2a), the creepage distance Y is not sufficient, and a desired withstand voltage is maintained due to scattering powder adhering thereto. Can not.
For this reason, the insulating wall 3 (indicated by a two-dot chain line in FIG. 21) protrudes from the base 1 to increase the creeping distance Y. The insulating wall 3 is formed at the same time as the base 1 is formed.

[0003]

However, when the electromagnetic relay is very small, the thickness of the insulating wall 3 erected from the base 1 needs to be very small because the distance between the contacts is small. For example, if the distance between contacts is 0.7
mm, the thickness of the insulating wall 3 needs to be 0.2 mm. It is very difficult to form such a thin insulating wall 3 because the resin hardly flows and short shots and burrs are generated.

Accordingly, an object of the present invention is to provide an electromagnetic relay which can easily and surely maintain insulation between contacts even if it is very small.

[0005]

According to the present invention, as a means for solving the above-mentioned problems, a groove is formed between adjacent fixed terminals inserted into a base to form a predetermined creepage distance. It is.

[0006] Further, between the fixed terminal insert-molded in the base and the fixed terminal inserted or press-fitted in the base,
A groove for forming a predetermined creepage distance is formed.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 and 2 show an example of an electromagnetic relay according to the present invention, and are exploded perspective views as seen from above and below, respectively. This electromagnetic relay generally includes a base block 20, an insulating block 30, and an electromagnet block 40.
And a case 60.

A base block 20 includes a base 21 having a first fixed terminal 22 and a movable contact piece 23 as a contact opening / closing mechanism.
In addition, the common terminal 24 is integrated.

The base 21 is formed in a substantially rectangular plate shape in a plan view. As shown in FIGS. 5 and 6, a rib 33 having a substantially U-shape in a plan view is protruded from one end side edge. Also, rib 3
In the vicinity of 3, the first fixed terminals 22 are arranged side by side at four places in the width direction and integrated. Each first fixed terminal 22 includes a first fixed contact 22 a exposed on the upper surface of the base 21 and first terminal portions 22 b protruding from both lower surfaces of the base 21.
Each first fixed contact 22a extends in the width direction of the base 21,
As shown in FIGS. 19 and 20, a creepage distance Y is set between the respective portions by a groove 26 formed in the base 21. That is, since the creepage distance Y is larger than the inter-contact distance (space distance X), the withstand voltage is larger on the creepage surface than in the space. Therefore, even if the scattered powder is generated from the contact due to the opening and closing of the contact and adheres to the creeping surface 21a, the creepage distance Y is sufficient and the withstand voltage of the creeping surface does not become lower than that of the space. Thereby, the density of the first fixed contact 22a is increased. The groove 26 formed outside the first fixed contact 22a located on both sides is provided with a predetermined creepage distance between the first fixed contact 22a and a second fixed contact 32a of a second fixed terminal 32 described later. This is for forming Y. In addition, the base 2
On both side edges of 1, an escape portion 27 for locking adjacent to both ends of the rib 25 and an insertion hole 28 located in the vicinity thereof are respectively formed.

On the other hand, a total of four common terminals 24 are provided at the other end of the base 21. Each common terminal 24
Has a welded portion 24a projecting from the upper surface of the base 21 and juxtaposed in the width direction, and terminal portions 24b projecting from both sides of the lower surface of the base 21. One end of the movable contact piece 23 is welded to each of the welding portions 24a. The free end of each movable contact piece 23 is bifurcated, and the movable contacts 23a and 23b are fixed respectively. The movable contact 23a is formed on the upper surface of the movable contact piece 23 located at two places on both sides. The movable contact 23b is formed on the lower surface of each movable contact piece. Further, positioning notches 23c are formed at the tips of the movable contact pieces 23 located at two places on both sides. A guide portion 29 protrudes upward from both edges of the other end of the base 21, and an insulating plate locking concave portion 29 a is formed therein. In addition, a coil block locking recess 21a is formed on the lower edge thereof (see FIG. 2). The base 21 has a recess 21b in a predetermined area including the protruding terminal portions 22b and 24b.
(See FIG. 18). This recess 21b
This is for suppressing the amount of the sealant used.

The insulating block 30 is a rectangular plate-like insulating plate 3.
1, a pair of second fixed terminals 32 are integrated.

As shown in FIG. 7, ribs 33 project upward from both side edges of the insulating plate 31, and a mounting portion 34 for mounting the second fixed terminal 32 downward is provided. , Insulating recess 2 for insulating plate of base 21
An engagement portion 35 that engages with 9a is protruded. The ribs 33 are connected to the respective contacts 22a, 23a, 32
This is for increasing the creeping distance Y between the coil a and the coil 50 to improve the insulating property. The mounting portion 34 has a rectangular hole 34a. In addition, on the lower surface of the insulating plate 31, a portion adjacent to each mounting portion 34 is one step higher than other portions. In addition, there is a bulging portion 36 (FIG. 2).
Reference) is formed. The swelling portion 36 is provided in the rectangular hole 3.
It has a fitting recess 36a opening toward 4a.

The second fixed terminal 32 has a rectangular plate shape, has a second fixed contact 32a (see FIG. 2) formed on the lower surface, and has a second terminal portion 32b extending downward. The second fixed terminal 32 includes the second terminal portion 32.
Notches 32c are formed on both sides of the base of b. The notch 32c allows the second fixed terminal 32 to be connected to the mounting portion 34.
Plays a role of generating a predetermined elastic force when pressed into the rectangular hole 34a. Further, the second fixed terminal 32 has a second
On the side opposite to the terminal portion 32b, a fitting projection 32d that fits into the fitting concave portion 36a of the bulging portion 36 is formed.

The electromagnet block 40 includes the coil block 4
1 and an armature block 51.

The coil block 41 has an iron core 49 provided on a spool 42 and a coil 50 (see FIG. 12) wound thereon.

As shown in FIG. 10, the spool 42 has a first flange 44 and a second flange 47 at both ends of a body 43, respectively. The body 43 has a plate shape, and the upper surface is depressed except for both side edges, and a locking projection 43a is formed inward at the center of both sides. The first flange portion 44 is provided with legs 45 projecting downward. An engagement claw 45a is formed on the front end facing surface of each leg 45 to engage with the locking relief portion 27 of the base 21. A guide recess 46 is formed at the center of the upper surface of the first flange 44, and guide protrusions 46a are formed on both sides thereof so as to be substantially U-shaped. On the other hand, guide walls 47a are erected at predetermined intervals on the second flange portion 47, and coil terminals 48 are press-fitted on both sides thereof. A window 47b (see FIG. 16) is provided below the second flange 47.
Are formed. A locking projection 47c is formed on the inner edge of the lower end forming the window 47b. Locking projection 47
c is a coil block locking recess 21 of the base 21.
a.

As shown in FIG. 10, the iron core 49 is formed by bending a magnetic plate material into a substantially U-shape and further bending both ends of the magnetic plate material horizontally outward, thereby forming a suction portion (magnetic pole portion) 49 at one end.
a, an attracting portion (magnetic pole portion) 49b is formed on the other end side. The central portion of the iron core 49 is placed on the upper surface of the spool 42, and both sides thereof are supported by the projections 43a.
At this time, the suction part 49 a of the iron core 49 is guided by the guide recess 46 of the first flange part 44 of the spool 42. Also,
The suction portion 49b is guided by the guide walls 47a (both sides) of the second flange portion 47, and a gap (snap-fit portion A) is formed between the two (between the end surface of the spool 42 and the end surface of the suction portion 49b). (See FIG. 12).

The coil 50 has a core 4 attached to a spool 42.
9 is placed around the body 43 of the spool 42 and the center of the iron core 49, and both ends are wound around the coil terminals 48, respectively.

The armature block 51 is obtained by integrating a movable iron piece 52 with a hinge spring 53.

As shown in FIG. 11, the movable iron piece 52 has a reduced thickness on both sides at one end, a notch 52a is formed therein, and a pair of caulking projections 52b is formed on the upper surface at the other end. ing.

The hinge spring 53 is formed by bending a rectangular frame-shaped elastic plate at a substantially right angle to fix the caulking projection 52b of the movable iron piece 52 in the through hole 53a at one end, while engaging the tongue at the other end. 54 are formed.

As shown in FIG. 1, the card 55 has a plate shape made of a synthetic resin, and has a substantially C-shaped elastic locking portion 56 formed on both upper sides thereof, and is locked by the notch 52a of the movable iron piece 52. It has become so. Locking projections 57 project downward from both sides of the lower portion of the card 55 so as to be locked in the positioning notches 23c of the movable contact piece 23, respectively.

The case 60 has a box shape with an opening at the bottom.
As shown in FIG. 2, a plurality of reinforcing ribs 61 are formed at the boundary between the ceiling wall and the side wall. On the inner surface of the lower opening, locking projections 62 that are locked to the lower surface edge of the base 21 are formed at positions facing each other.
Note that 60a shown in FIG. 15 is a gas vent hole, which is sealed after the completion of the electromagnetic relay.

Next, a method of manufacturing the electromagnetic relay having the above configuration will be described.

In the processing of the base block 20, a strip-shaped metal plate is punched out by pressing to form a lead frame 70 (see FIG. 3). In this lead frame 70,
First positioning holes 72 formed in both side edges 71
The fixed terminal 22 and the common terminal 24 are respectively formed at predetermined positions. Further, by the press working, the portion B of the first fixed terminal 22 to which the first fixed contact 22a is welded and the welded portion 24a of the common terminal 24 are bent into a predetermined shape. Further, first alignment holes 74 are formed at a predetermined pitch in the first connection portion 73 connecting the welded portions 24a to each other.

Subsequently, the lead frame 70 is positioned in a mold (not shown) using the positioning holes 72, and the base 21 is formed by injection molding (see FIG. 4). At this time, the first fixed contact 2 of each first fixed terminal 22
2a, a groove 2 for forming a desired creepage distance Y
6 are formed. The groove 26 can be easily formed only by forming a protrusion on the mold. Further, the protrusion does not hinder the flow of the resin in the cavity as in the related art, and no defect occurs in the base 21. The terminal portions 22b and 24b of the first fixed terminal 22 and the common terminal 24 are cut from the lead frame 70,
It is bent downward (see FIG. 5).

On the other hand, the movable contact piece 23 is formed by press working (see FIG. 5). One end of each movable contact piece 23 is bent upward. In this case, the movable contact pieces 23 located on both sides are movable contact pieces 23 located at two central positions.
It bends so that the bending angle becomes large as compared with.

The movable contact piece 23 is punched out with the other end side connected by a second connecting portion 75, and the second connecting portion 75 has a second position corresponding to the first alignment hole 74. 2
An alignment hole 76 is formed.

Therefore, the welding portion 24a of the common terminal 24 and the movable contact piece 23 are aligned so that the alignment holes 74 and 76 communicate with each other, and are integrated by welding.
Cut (see FIG. 6).

In the processing of the insulating block 30, the insulating plate 31 is formed by injection molding. Further, the second fixed terminal 32 is formed by press working. Then, the second fixed terminal 32
Through the rectangular hole 34a formed in the mounting portion 34 of the insulating plate 31 (see FIG. 7). Fitting protrusion 32 of second fixed terminal 32
d fits into the fitting recess 36a of the insulating plate 31. The second fixed terminal 32 itself is elastically deformed by the notch 32c and is press-fitted into the rectangular hole 34a. Thereby, the second fixed terminal 32 is fixed to the insulating plate 31 (see FIG. 8).

In the processing of the electromagnet block 40, the spool 42 is formed by injection molding. And the second flange 47
The coil terminal 48 is press-fitted. Further, an iron core 49 bent into a predetermined shape from above is placed. Then, spool 4
2 around the body 43 and the intermediate part of the iron core 49.
, And both ends are wound around each coil terminal 48.

In the processing of the armature block 51, the movable iron piece 52 and the hinge spring 53 are formed by pressing. Then, a hinge spring 53 is swaged and fixed to the movable iron piece 52.

The case 60 is formed by injection molding.

Thus, each of the blocks 20, 30, 4
0 and the case 60 are completed, the base block 2
The insulating block 30 is assembled from above to the 0 (see FIG. 9). In this case, the engaging portion 35 of the insulating plate 31 is
Both are easily integrated by engaging with the insulating plate locking concave portion 29a. At this time, the second terminal portion 32b of the second fixed terminal 32 projects downward through the insertion hole 28 formed in the base 21.

Next, a coil block 41 is mounted on the insulating block 30 from above (see FIG. 12). In this case, the movable contact piece 23 welded to the welding portion 24a of the common terminal 24 is inserted into the window 47b formed on the second flange portion 47 of the coil block 41 from an obliquely upper side so as to be inserted. After the locking projection 47c is locked to the coil block locking recess 21a, the locking claw 45 of the leg 45 is locked.
a is locked to the locking relief portion 27 (see FIG. 12).

Subsequently, the armature block 51 is assembled from above the coil block 41. In this case, the locking tongue piece 54 of the hinge spring 53 is inserted into the snap-fit portion A formed between the guide wall 47a and the suction portion 49b of the iron core 49. As a result, the locking tongue piece 54 is inserted into the snap-fit portion A while being elastically deformed, then returns to its shape, and is locked to the lower edge of the suction portion 49b (FIG. 17).
reference). Therefore, the hinge spring 53 does not come into contact with the resin molded product such as the base 21 and does not damage the resin molded product due to the turning operation of the movable iron piece 52. In this case, since the hinge spring 53 is guided by the guide wall 47a, the locked state is not released.

Thereafter, the card 55 is assembled from obliquely above. The card 55 is assembled by inserting the locking projection 57 into the positioning notch 23c of the movable contact piece 23 and then locking the elastic locking part 56 to the notch 52a of the movable iron piece 52. However, the card 55 may be assembled to the movable iron piece 52 before the armature block 51 is assembled.

In this way, each of the blocks 20, 30, 4
0, the window 47b of the spool 42
By deforming one end of the movable contact piece 23 together with the welded portion 24a of the common terminal 24 via (see FIG. 16), the distance between the movable contact 23a and the fixed contacts 22a and 32a is adjusted. In this manner, by forming the window portion 47b, since the adjustment can be performed from the side after the assembly, the distance between the contacts can be adjusted easily and accurately.

Finally, cover the base 21 with the case 60,
The electromagnetic relay is completed by filling the recess 21b on the lower surface shown in FIG. 18 with a sealant.

Next, the operation of the electromagnetic relay will be described.

When the coil block 41 in which the coil 50 is not energized is in the non-excited state, as shown in FIG. 17A, the movable iron piece 52 is moved by the elastic force of the hinge spring 53 and the movable contact pieces 23 located on both sides. Energized, iron core 49
Is separated from the suction part 49a. Thereby, each movable contact piece rotates upward via the card 55.
Each movable contact 23a on the lower surface is separated from each first fixed contact 22a exposed on the upper surface of the base 21. Further, the movable contact 23a on the upper surface side of the movable contact piece 23 located on both sides is closed to the second fixed contact 32a.

Here, when the coil 50 is energized by energizing the coil 50, the suction force of the iron core 49 at the suction part 49a exceeds the elastic force, and one end of the movable iron piece 52 is connected to the suction part 49a of the iron core 49. It is sucked. As a result, each movable contact piece 23 rotates downward via the card 55, and each movable contact 23a on the lower surface side is connected to each first fixed contact 2 of the base 21.
Close to 2a. When the coil block 41 is degaussed by interrupting the energization of the coil 50, the movable contact piece 23 returns to the original position by its own elastic force, and the movable contact 2
3b is separated from the first fixed contact 22a, and the movable contact 23a
Is closed to the second fixed contact 32a.

Even if the contacts are opened and closed in this way,
As shown in FIG. 19, a desired creepage distance Y is formed between the first fixed contacts 22a and between the first fixed contacts 22a and the second fixed contacts 32a by the groove portions 26, so Is maintained at a desired withstand voltage, and the insulation is not hindered. In addition, even if scattered powder is generated from the contact point due to long-term use, the scattered powder is not affected by the creepage distance Y.
Is merely adhered in the groove portion 26 in which the insulating property is sufficiently secured, and the insulating property is not hindered.

[0045]

As is apparent from the above description, according to the electromagnetic relay of the present invention, a groove for forming a predetermined creepage distance is formed between each fixed terminal. A predetermined creeping distance can be formed between the fixed terminals, and desired insulation can be obtained.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an electromagnetic relay according to an embodiment viewed from above.

FIG. 2 is an exploded perspective view of the electromagnetic relay according to the embodiment as viewed from below.

FIG. 3 is a perspective view of a lead frame.

FIG. 4 is a perspective view showing a state in which a case is formed on the lead frame of FIG. 3 by injection molding.

FIG. 5 is an exploded perspective view of a base block.

FIG. 6 is a perspective view of a base block.

FIG. 7 is an exploded perspective view of an insulating block.

FIG. 8 is an exploded perspective view of a base block and an insulating block.

FIG. 9 is a perspective view showing a state where an insulating block is assembled to a base block.

FIG. 10 is an exploded perspective view of a coil block.

FIG. 11 is an exploded perspective view of the armature block.

FIG. 12 is a perspective view showing a state where the coil block is assembled in FIG. 9;

FIG. 13 is a perspective view showing a state where the armature block is assembled in FIG.

FIG. 14 is a perspective view showing a state where the card is assembled in FIG.

FIG. 15 is a perspective view showing a state in which a case is put on FIG. 14;

FIG. 16 is a perspective view showing a state where FIG. 15 is viewed from different angles.

17 is a sectional view taken along line II of FIG. 16 (a) and a partially enlarged view thereof (b).

FIG. 18 is a perspective view showing a state where FIG. 15 is viewed from the bottom surface side.

FIG. 19 is a sectional view of the base block of FIG. 1;

FIG. 20 is a partial cross-sectional view showing the vicinity of a first fixed terminal of a base block.

FIG. 21 is a partial cross-sectional view showing the vicinity of a first fixed terminal of a base block according to a conventional example.

[Explanation of symbols]

 21 Base 22 Fixed terminal 22a Fixed contact 26 Groove

Claims (2)

[Claims] 1. An electromagnetic relay, wherein a groove for forming a predetermined creepage distance is formed between adjacent fixed terminals insert-molded on a base. 2. An electromagnetic relay, wherein a groove for forming a predetermined creepage distance is formed between a fixed terminal insert-molded on a base and a fixed terminal inserted or pressed into the base.