Electromagnetic relay

This application is based on a Japanese Patent Applications Hei. 11-304734 filed on Oct. 26, 2000, Hei. 11-322700 filed on Nov. 12, 1000 and 2000-182211 filed on Jun. 16, 2000, herein cooperated by reference.

BACKGROUND OF INVENTION

1. Field of Application

The present invention relates to an electromagnetic relay constituted by a yoke, a coil portion wound onto the yoke, an armature toggled and provided with respect to the yoke, and a moving contact and a fixed contact which are brought into a contact and separation state depending on the toggle motion of the armature.

2. Related art

FIGS. 1

to

3

show a conventional electromagnetic relay of this type. The electromagnetic relay comprises a yoke C having a winding space divided by a coil bobbin A, a coil B wound thereon and magnetic pole portions C

1

and C

2

provided on both ends, a pair of armatures D

1

and D

2

which are attracted into and separated from the magnetic pole portions C

1

and C

2

of the yoke C to be rotated depending on the excitation state of the coil B, a fixed contact plate E provided with a fixed contact E

1

, a movable spring F provided with a moving contact F

1

opposite to the fixed contact E

1

, and a card G linked to the armatures D

1

and D

2

for displacing the movable spring F such that the moving contact F

1

abuts on or separates from the fixed contact E

1

depending on the rotating operation of the armatures D

1

and D

2

.

The yoke C forms a coil block CC together with the coil bobbins A and B. Moreover, the armatures D

1

and D

2

interpose a permanent magnet H therebetween, and is formed of a molding material integrally with the permanent magnet H. Thus, an armature block DD is formed. A portion J thus formed integrally is provided with a support portion J

1

rotatably supported on a body K in which parts such as the armature block DD and the coil block CC are arranged, and furthermore, is provided with a lever J

2

extended and linked to one of ends of the card G having the other end connected to the movable spring F.

The lever J

2

is connected to the yoke C through an adjusting spring L to be rotatably supported in a state in which a clearance GG is formed between both magnetic pole portions C

1

and C

2

of the yoke C respectively. The clearance GG between the magnetic pole portions C

1

and C

2

of the yoke C and the armatures D

1

and D

2

is regulated by properly changing the shape of the adjusting spring L. By thus regulating the clearance GG, a working voltage of the abutting and separating operation of both contacts E

1

and F

1

can be regulated so that a sensitivity of the abutting and separating operation of the contacts E

1

and F

1

can be regulated.

When a current is caused to flow in a preset direction so that the coil B is excited, an end D

11

of the armature D

1

is attracted into the magnetic pole portion C

1

on one end of the yoke C and the other end D

22

of the armature D

2

is attracted into the magnetic pole portion C

2

on the other end of the yoke C such that a closed magnetic circuit is formed. Consequently, the armature block DD is rotated clockwise in FIG.

17

. As a result, the card G linked to the lever J

2

of the armature block DD is driven toward the movable spring F, and the movable spring F connected to the driven card G is displaced toward the fixed contact plate E so that the moving contact F

1

of the movable spring F abuts on the fixed contact E

1

of the fixed contact plate E. When the excitation of the coil B is stopped, this state is held.

When a current is caused to flow in a direction reverse to the above-mentioned direction so that the coil B is excited in this state, an end D

12

of the armature D

1

is attracted into the magnetic pole portion C

2

on the other end of the yoke C and one end D

21

of the armature D

2

is attracted into the magnetic pole portion C

1

on one end of the yoke C such that a closed magnetic circuit is formed. Consequently, the armature block DD is rotated counterclockwise in FIG.

2

. As a result, the card G linked to the lever J

2

of the armature block DD is driven in such a direction as to go away from the movable spring F, and the movable spring F connected to the driven card G is displaced apart from the fixed contact plate E so that the moving contact F

1

of the movable spring F is separated from the fixed contact E

1

of the fixed contact plate E. When the excitation of the coil B is stopped, this state is held.

With such a structure, however, the armature block DD is positioned in three points, that is, the magnetic pole positions B

1

and B

2

and the fulcrum J

1

. Therefore, a variation in the dimensions of parts causes a clearance to be generated between the end of the magnetic pole portion C

2

and the armature D

22

of the armature block J in either of the magnetic pole positions B

1

and B

2

(the B

2

side in an example of

FIG. 3

) as shown in FIG.

3

. As a result, a fluctuation in a magnetic characteristic is increased so that a shock resistance is deteriorated. Moreover, it is very difficult to regulate a sensitivity.

In this phenomenon, the following troublesome are to be caused , as shown in

FIG. 2

, the clearance GG is formed in two portions between the armatures D

1

and D

2

and the magnetic pole portions C

1

and C

2

of the yoke C. Therefore, in a state in which the sensitivity of the abutting and separating operation of the contacts E

1

and F

1

is regulated, the clearance GG in at least one of the two portions remains so that a variation in suction force is increased. Consequently, it is hard to regulate the sensitivity of the abutting and separating operation of the contacts E

1

and F

1

.

SUMMARY OF INVENTION

The invention has been made in consideration of the circumstances and has an object to provide an electromagnetic relay in which a fluctuation in a magnetic characteristic is small, a shock resistance is enhanced and a sensitivity can be regulated easily.

Another object is to provide an electromagnetic relay capable of easily regulating a sensitivity of the abutting and separating operation of both contacts.

In order to solve the problem, a first aspect of the invention is directed to an electromagnetic relay comprising a yoke having both ends bent in one direction, a coil portion wound onto a central part between the ends of the yoke, a permanent magnet provided between the ends of the yoke, an armature formed to have a greater length than that between the ends of the yoke and provided on the one direction side with respect to the permanent magnet, and a hinge spring capable of causing both end sides of the armature to be toggled with respect to the ends of the yoke, thereby integrally fixing the permanent magnet and the armature, wherein a protrusion is provided between the permanent magnet and the armature.

With such a structure, the position of the armature is determined by two points of the protrusion and either of the positions of magnet poles. Therefore, an unnecessary clearance is not generated so that a magnetic gap is not caused. Consequently, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

The electromagnetic relay according to the first aspect of the invention may further comprise an auxiliary yoke formed like a plate having a length which is almost equal to the length between the ends of the yoke and provided on a side reverse to the one direction with respect to the permanent magnet, the permanent magnet being formed like a plate having a smaller length than that between the ends of the yoke, the armature being formed like a plate and having the protrusion on a face opposed to the permanent magnet, the hinge spring being formed to have a central part attached to a face on the one direction side in the armature and both side parts extended from the central part in a direction reverse to the one direction, attached to both side faces of the auxiliary yoke respectively, and having both side parts interposing the permanent magnet therebetween, and the permanent magnet, the armature and the auxiliary yoke being integrally fixed with the hinge spring. According to such a structure, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

In the electromagnetic relay according to the first aspect of the invention, the permanent magnet may be formed like a plate having a length which is almost equal to that between the ends of the yoke, the armature may be formed like a plate and may have the protrusion on a face opposed to the permanent magnet, the hinge spring may be formed to have a central part attached to a face on the one direction side in the armature and both side parts extended from the central part in a direction reverse to the one direction and attached to both side faces of the permanent magnet respectively, and the permanent magnet and the armature may be integrally fixed with the hinge spring. According to such a structure, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily. Furthermore, a size can be reduced still more.

The electromagnetic relay according to the first aspect of the invention may further comprise an auxiliary yoke formed like a plate having a length which is almost equal to the length between the ends of the yoke and provided on a side reverse to the one direction with respect to the permanent magnet, the permanent magnet being formed like a plate having a smaller length than that between the ends of the yoke, the armature being formed like a plate and having the protrusion on a face opposed to the permanent magnet, the hinge spring being formed to have a central part attached to a face on a direction side reverse to the one direction in the armature and both side parts extended from the central part in the reverse direction, attached to both side faces of the auxiliary yoke respectively and interposing the permanent magnet therebetween, and the permanent magnet, the armature and the auxiliary yoke being integrally fixed with the hinge spring. According to such a structure, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily. Furthermore, it is possible to suitably prevent wear from being caused by a toggle motion of an armature block including the permanent magnet, the armature and the auxiliary yoke which are integrated with the hinge spring.

The electromagnetic relay according to the second or fourth aspect of the invention may further comprise a device body having a body and a cover, the auxiliary yoke having a fixing portion to the body. With such a structure, assembly can easily be carried out.

In the electromagnetic relay according to the fifth aspect of the invention, the fixing portion may include a plurality of protrusions and the body may be provided with a groove in which the protrusion is to be fitted. With such a structure, assembly can easily be carried out.

The electromagnetic relay according to any of the first to sixth aspects of the invention may further comprise a fixed contact spring block including a fixed side terminal, a leaf spring fastened to the fixed side terminal, and a fixed contact provided on the leaf spring, a moving contact spring block including a moving side terminal, a leaf spring fastened to the moving side terminal and a moving contact provided on the leaf spring, and a card attached to both of the armature and the moving contact spring block for causing the fixed contact and the moving contact to come in contact with or separate from each other depending on a toggle motion of the armature. According to such a structure, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

As is apparent from the foregoing, according to the seventh aspect of the invention, an electromagnetic relay comprises a yoke having both ends bent in one direction, a coil portion wound onto a central part between both ends of the yoke, a plate-shaped permanent magnet having a smaller length than that between the ends of the yoke, an auxiliary yoke formed like a plate having a length which is almost equal to that between the ends of the yoke and provided in a direction reverse to the one direction with respect to the permanent magnet, an armature formed to have a greater length than that between the ends of the yoke and attraced into or separated from a magnetic pole portion of the yoke for being rotated depending on an excitation state of the coil portion, a hinge spring for causing both end sides of the armature to be toggled, thereby integrally fixing the permanent magnet, the auxiliary yoke and the armature, a fixed contact plate having a fixed contact, a movable spring having a moving contact opposed to the fixed contact, and a card engaged with the armature for displacing the movable spring such that the moving contact abuts on or separates from the fixed contact depending on a rotating operation of the armature, wherein the hinge spring has a central part attached to a surface in the one direction of the armature and both ends extended from the central part in a direction reverse to the one direction and attached to both side walls of the auxiliary yoke through concavo-convex fitting with the armature and the permanent magnet held, and the auxiliary yoke has a concavo-convex disengagement prevention structure. Therefore, it is possible to provide an electromagnetic relay which changes a characteristic with difficulty even if a vibration or an impact is applied.

According to the eighth aspect of the invention, in the electromagnetic relay according to the seventh aspect of the invention, the hinge spring has a hole on each of both ends and the auxiliary yoke has a protrusion fitted in each hole on the both ends, the protrusion being bent in the direction reverse to the one direction as the disengagement prevention structure. Therefore, the protrusion bent in the direction reverse to the one direction engages the peripheral portion of the hinge spring. Consequently, the protrusion slips off from the hole of the hinge spring with difficulty.

According to the ninth aspect of the invention, in the electromagnetic relay according to the seventh aspect of the invention, the hinge spring has a hole on each of both ends and the auxiliary yoke has a protrusion fitted in each hole on the both ends, the protrusion having, as the disengagement prevention structure, a V-shaped groove for fitting the peripheral portions of the corresponding holes of the ends on the surface in the direction reverse to the one direction. Therefore, the peripheral portion of the corresponding hole is fitted in the V-shaped groove. Consequently, the protrusion slips off from the hole of the hinge spring with difficulty.

According to the tenth aspect of the invention, in the electromagnetic relay according to the seventh aspect of the invention, the hinge spring has a hole on each of both ends and the auxiliary yoke has a protrusion fitted in each hole on the both ends, the protrusion having, as the disengagement prevention structure, a hook-shaped click portion extended in the direction reverse to the one direction. Therefore, the click portion provided on each protrusion engages the peripheral portion of the hole of the hinge spring. Consequently, the protrusion slips off from the hole of the hinge spring with difficulty.

According to the eleventh aspect of the invention, if the opposed distance between both contacts is regulated to be smaller by elastically deforming the movable spring in the direction of the displacement thereof, the sensitivity of the abutting and separating operation of the contacts is increased. To the contrary, if the opposed distance between the contacts is regulated to be longer, the sensitivity of the abutting and separating operation of the contacts is reduced. Consequently, the sensitivity of the abutting and separating operation of the contacts can be regulated. Thus, the sensitivity of the abutting and separating operation of the contacts can be regulated by elastically deforming the movable spring in the direction of the displacement thereof. Therefore, it is not necessary to provide a clearance for sensitivity regulation between the magnetic pole portion of the yoke and the armature, and suction force is not varied. Consequently, the sensitivity of the abutting and separating operation of the contacts can be regulated easily.

According to the twelfth aspect of the invention, in addition to the effects of the electromagnetic relay according to the eleventh aspect of the invention, the movable spring is elastically deformed by the pressing portion in the direction of the displacement thereof. Therefore, the amount of elastic deformation can be regulated by increasing or reducing the pressing force of the pressing portion. Furthermore, the sensitivity of the abutting and separating operation of the contacts can be regulated easily.

According to the thirteenth aspect of the invention, in addition to the effects of the electromagnetic relay according to the twelfth aspect of the invention, the pressing portion is provided on the movable terminal itself. Therefore, it is not necessary to provide the pressing portion by particularly paying attention such that the pressing portion abuts on the movable terminal to generate a mutual interference. Thus, assembly can be carried out easily.

According to the fourteenth aspect of the invention, in addition to the effects of the electromagnetic relay according to the twelfth or thirteenth aspect of the invention, the movable spring locally decreases the spring force of the portion to be pressed by the pressing portion. Therefore, slight elastic deformation can be carried out in the direction of the displacement, and the sensitivity of the abutting and separating operation of the contacts can be regulated with high precision.

According to the fifteenth aspect of the invention, in addition to the effects of the electromagnetic relay according to any of the twelfth to fourteenth aspects of the invention, the press state of the pressing portion can be adjusted by elastically deforming the portion to be pressed by the pressing portion in the direction of the displacement. Therefore, the elastic deformation can be slightly adjusted in the direction of the displacement, and the sensitivity of the abutting and separating operation of the contacts can be regulated with high precision.

According to the sixteenth aspect of the invention, in addition to the effects of the electromagnetic relay according to any of the eleventh to fifteenth aspects of the invention, the current also flows to the contact portion extended from the fixed terminal as well as the fixed contact plate when both contacts abut. Therefore, the current flowing to the fixed contact plate can be decreased so that heat generation can be suppressed.

According to the seventeenth aspect of the invention, in addition to the effects of the electromagnetic relay according to the sixteenth aspect of the invention, the fixed contact plate obtains the prepressures of both contacts. Therefore, the contact pressure can be obtained through the abutment of the contacts.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1

is a perspective view showing a conventional example.

FIG. 2

is a front view showing an operation according to the conventional example.

FIG. 3

is a view illustrating the drawback of the electromagnetic relay shown in FIG.

2

.

FIG. 4

is a perspective view showing an electromagnetic relay according to a first embodiment of the invention, which is partially taken away.

FIGS.

5

(

a

) to

5

(

d

) are perspective views showing a fixed contact spring block, a moving contact spring block, a yoke and a card illustrated in

FIG. 1

, respectively.

FIGS.

6

(

a

) and

6

(

b

) are exploded perspective views showing an armature block illustrated in

FIG. 4

, respectively.

FIGS.

7

(

a

) and

7

(

b

) are views showing an electromagnet block and the armature block illustrated in

FIG. 4

as seen from the front and the right, respectively.

FIGS.

8

(

a

) and

8

(

b

) are a partial front view and a sectional view taken along the line A—A in

FIG. 4

, respectively.

FIG. 9

is a view showing an example of another structure for fixing a hinge spring to an auxiliary yoke.

FIGS.

10

(

a

) and

10

(

b

) are views showing an electromagnet block and an armature block in an electromagnetic relay according to a second embodiment of the invention as seen from the front and the right, respectively.

FIGS.

11

(

a

) and

11

(

b

) are views showing an electromagnet block and an armature block in an electromagnetic relay according to a third embodiment of the invention as seen from the front and the right, respectively.

FIGS.

12

(

a

) and

12

(

b

) are views showing a hinge spring of

FIG. 11

seen from the front and the right, respectively.

FIGS. 13

a-c

are views showing an armature block of an electromagnetic relay according to a fourth embodiment of the invention.

FIGS. 14

a-c

are views showing an auxiliary yoke of the electromagnetic relay according to the fourth embodiment.

FIGS. 15

a-c

are views showing an auxiliary yoke of an electromagnetic relay according to a fifth embodiment of the invention.

FIGS. 16

a-c

are views showing an armature block of the electromagnetic relay according to the fifth embodiment.

FIGS. 17

a-c

are views showing an auxiliary yoke of an electromagnetic relay according to a sixth embodiment of the invention.

FIGS. 18

a-c

are views showing an armature block of the electromagnetic relay according to the sixth embodiment.

FIG. 19

is a side view showing a contact separating state according to a seventh embodiment of the invention.

FIG. 20

is a perspective view showing the contact separating state.

FIG. 21

is a perspective view showing a moving terminal block according to the embodiment of the invention.

FIG. 22

is a perspective view showing a fixed terminal block according to the embodiment of the invention.

FIG. 23

is a front view showing the moving terminal block according to the embodiment of the invention.

FIG. 24

is a side view showing the moving terminal block according to the embodiment of the invention.

FIG. 25

is a sectional view taken along the line X—X in FIG.

19

.

FIG.

26

(

a

) is a side view showing a contact abutting state according to the embodiment of the invention.

FIG.

26

(

b

) is a partially enlarged view of FIG.

26

(

b

) and a current flow of electromagnetic repulsion)

FIG.

27

(

a

) is a sectional view taken along the line Y—Y in FIG.

26

(

a

).

FIG.

27

(

b

) is a side view showing the contact position.

FIG.

27

(

c

) shows a relationship between a contact position and a contact pressure which is obtained with or without application of the prepresssure

FIG. 28

is a front view showing the moving terminal block provided with a movable spring having no cut portion.

FIG. 29

is a front view showing g the moving terminal block provided with the movable spring having a notch-shaped cut portion.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

First Embodiment

FIG. 4

is a perspective view showing an electromagnetic relay according to a first embodiment of the invention, which is partially taken away,

FIG. 5

is a perspective view showing a fixed contact spring block, a moving contact spring block, a yoke and a card which are illustrated in

FIG. 4

,

FIG. 6

is an exploded perspective view showing an armature block illustrated in

FIG. 4

,

FIG. 7

is a view showing an electromagnet block and an armature block illustrated in

FIG. 4

as seen from the front and the right, and

FIG. 8

is a partial front view of

FIG. 4 and a

sectional view taken along the line A—A. With reference to these drawings, the first embodiment will be described below. In FIG.

7

(

a

), B denotes a magnetic pole position and C denotes a center of rotation. In FIG.

7

(

b

), D in a hinge spring denotes a twisted portion.

The electromagnetic relay shown in

FIG. 4

belongs to a so-called latch type, and is roughly divided into a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, an armature block

14

, a card

15

and a device body

16

for accommodating each part therein.

As shown in FIG.

5

(

a

), the fixed contact spring block

11

is constituted by a fixed side terminal

111

formed by bending a metal plate, a leaf spring

112

made of metal which has a lower end fastened to the upper end of the fixed side terminal

111

through a rivet, and a fixed contact made of metal which is fastened to the upper portion of the leaf spring

112

. The fixed contact is fastened to a cylindrical bottomed groove which is formed on the left surface (the back face in FIG.

5

(

a

)) of the leaf spring

112

and has a contact portion protruded toward the left.

As shown in FIG.

5

(

b

), the moving contact spring block

12

is constituted by a moving side terminal

121

made of a metal plate, a leaf spring

122

made of metal which has a lower end fastened to the upper end of the moving side terminal

121

through a rivet, and a moving contact

123

made of metal which is fastened to the upper portion of the leaf spring

122

. A protruded piece

122

a

for attaching the card

15

is protruded upward from the upper end of the leaf spring

122

.

As shown in

FIG. 4

, the electromagnet block

13

is constituted by a yoke

131

formed to take such a shape as to have both T-shaped ends

131

a

bent to the right (see FIG.

5

(

c

)), a bobbin

132

made of a resin, a coil portion

133

having a coil wire wound onto a central portion between both ends

131

a

of the yoke

131

through the bobbin

132

, and a pair of coil terminals

134

fastened integrally with the lower end side of the bobbin

132

to which both ends of the coil portion

133

are connected (through soldering, for example). Moreover, a groove (not shown) for inserting the yoke

131

is formed on the rear face side of the bobbin

132

.

The procedure for manufacturing the electromagnet block

13

will be described. First of all, the yoke

131

is inserted in the groove of the bobbin

132

and the coil wire is wound onto the bobbin

132

to provide the coil portion

133

. Subsequently, both ends of the coil portion

133

are connected to the coil terminals

134

, respectively. Consequently, the electromagnet block

13

is obtained.

The armature block

14

is constituted by a permanent magnet

141

, an armature

142

, an auxiliary yoke

143

and a hinge spring

144

as shown in

FIGS. 4 and 6

.

The permanent magnet

141

is formed to take a plate shape (a rectangular parallelepiped in the example of FIG.

6

(

b

)) having a smaller vertical length than that between both ends

131

a

of the yoke

131

and is provided such that the right face side is slightly protruded from both ends

131

a

of the yoke

131

. Moreover, the permanent magnet

141

is polarized such that the right face side has an S pole and the left face side has an N pole or the right face side has the N pole and the left face side has the S pole before/after the assembly of the electromagnetic relay. For example, if the permanent magnet

141

is polarized after the assembly of the electromagnetic relay, it is possible to prevent iron powder from being stuck and mixed into the electromagnetic relay.

The armature

142

is formed like a plate to have a greater vertical length than that between both ends

131

a of the yoke

131

. As shown in FIG.

6

(

b

), the armature

142

includes a protrusion

142

a

for attaching the card

15

protruded toward the upper end, a protrusion

142

b

protruded toward the center on the left face (see FIG.

7

(

a

)), and a pair of shaft portions

142

c

protruded toward the upper and lower sides on the right face for rivet fastening, and is provided on the right side with respect to the permanent magnet

141

as shown in FIG.

7

.

The auxiliary yoke

143

is formed like a plate to have a slightly smaller vertical length than that between the ends

131

a

of the yoke

131

, includes a protrusion

143

a

serving to fix the hinge spring

144

and protruded toward the center of each of the front and rear side walls, a pair of protrusions

143

b

serving to fix the auxiliary yoke

143

to the device body

16

and protruded between both end sides of the rear side wall, and two holes

143

c

penetrating in a transverse direction, and is provided on the left side with respect to the permanent magnet

141

as shown in FIG.

7

(

a

).

The hinge spring

144

has a central portion

144

a

which serves to fix the permanent magnet

141

, the armature

142

and the auxiliary yoke

143

integrally, is formed of a thin metallic plate having elasticity, is formed like a cross extended in longitudinal and vertical directions and is attached to the right face of the armature

142

, and both side portions

144

b

formed like a cross extended in vertical and horizontal directions, extended toward the left from the front and rear ends of the central portion

144

a

and attached to the front and rear side faces of the auxiliary yoke

143

as shown in FIG.

6

(

b

). Moreover, a hole

144

d in which the shaft portion

142

c

of the armature

142

is to be inserted is formed in each portion extended in the vertical direction of the central portion

144

a

. Furthermore, a hole

144

e

in which the protrusion

143

a

of the auxiliary yoke

143

is to be fitted is formed in a portion extended toward the left of each side portion

144

b

. In addition, a protruded piece

144

f

for preventing the vertical movement of the permanent magnet

141

is formed on the upper and lower ends of the side portion

144

b.

The procedure for assembling the armature block

14

will be described. First of all, the corresponding shaft portion

142

c

of the armature

142

is inserted into the hole

144

d

of the hinge spring

144

. Subsequently, the tip side of the shaft portion

142

c

is caulked. Consequently, the armature

142

and the hinge spring

144

are fastened to each other. Then, the permanent magnet

141

is interposed between both side portions

144

b

and the corresponding protrusion

143

a

of the auxiliary yoke

143

is thereafter fitted in the hole

144

e

of the hinge spring

144

. Consequently, it is possible to obtain the armature block

14

having the permanent magnet

141

, the armature

142

and the auxiliary yoke

143

fixed integrally with the hinge spring

144

.

As shown in FIG.

5

(

d

), the card

15

is formed of a resin like a plate, and has a hole

15

a

formed on the right end side for fitting the protruded piece

122

a

of the moving contact spring block

12

therein, a hole

15

b

formed on the left end side for fitting the protrusion

142

a

of the armature

142

therein, and a hole

15

c

extended in a transverse direction.

The device body

16

is constituted by a body

161

made of a resin and a cover

162

as shown in FIG.

4

. The body

161

has partition walls

161

a

to

161

e

serving to accommodate and fix the fixed contact spring block

11

and the moving contact spring block

12

and protruded from the right side portion in a forward direction, a groove

161

f

in which each protrusion

143

b

of the auxiliary yoke

143

is to be fitted (see FIG.

5

(

b

)), a groove

161

g

in which the lower end side of each end

131

a

of the yoke

131

is to be fitted (see FIG.

5

(

b

)), a protrusion (not shown) which is inserted in the hole

15

c

of the card

15

to regulate the transverse movement of the card

15

and is protruded toward the upper face of the partition wall

161

e

, and a pair of holes (not shown) in which a pair of coil terminals

134

of the electromagnet block

13

are to be inserted. The grooves

161

f

and

161

g

for fitting are provided to have such shapes as to correspond to the outer shapes of the fitting portions of the protrusion

143

b

and the end

131

a

respectively, for example. Consequently, the relationship of arrangement between the electromagnet block

13

and the armature block

14

can be managed with predetermined precision. On the other hand, the cover

162

is formed to have the shape of a box for blocking the front face side of the body

161

.

Next, description will be given to an example of the procedure for assembling the electromagnetic relay having such a structure. First of all, the fixed contact spring block

11

and the moving contact spring block

12

are accommodated and fixed into a predetermined position of the body

161

. At this time, it is more desirable that an adhesive should be used.

Then, each protrusion

143

b

of the armature block

14

is fitted in the corresponding groove

161

f

of the body

161

to fix the armature block

14

to the body

161

. At this time, it is more desirable that an adhesive should be used.

Thereafter, each coil terminal

134

of the electromagnet block

13

is inserted in the corresponding hole of the body

161

. Subsequently, the lower end side of each end

131

a

of the yoke

131

is fitted in the corresponding groove

161

g

to fix the electromagnet block

13

to the body

161

. At this time, it is more desirable that an adhesive should be used.

Then, the protruded piece

122

a

of the moving contact spring block

12

and the protrusion

142

a

of the armature

142

are fitted in the holes

15

a

and

15

b

of the card

15

, respectively. Subsequently, the cover

162

is put and fixed onto the body

161

. Thus, the electromagnetic relay is obtained.

In the electromagnetic relay thus assembled, the position of the armature

142

is determined by two points of the protrusion

142

b

and the position of a magnet pole (B in the example of FIG.

7

(

a

)) as shown in FIG.

7

(

a

). Therefore, an unnecessary clearance is not generated so that a magnetic gap is not caused. Consequently, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

In addition to the integral structure of the armature block

14

, furthermore, the protrusion

143

b

for fixing the armature block

14

to the body

161

is provided on the auxiliary yoke

143

as well as the function of a magnetic path for causing a magnetic flux to flow. Thus, the electromagnetic relay can be assembled easily.

While a pair of protrusions

143

a

are provided on the auxiliary yoke

143

to attach the hinge spring to the auxiliary yoke in the first embodiment, it is also possible to employ another structure for attaching the hinge spring to the auxiliary yoke without the protrusion

143

a

provided, for example. An example of the structure is shown in FIG.

9

. In

FIG. 9

, an auxiliary yoke

243

is formed to have the same shape as that of the auxiliary yoke

143

except that the protrusion

143

a

is removed. On the other hand, a hinge spring

244

is formed to have the same shape as that of the hinge spring

144

except that an engagement protrusion

244

g

with the auxiliary yoke

243

is formed on the left of the hole

144

e.

Second Embodiment

FIG. 10

is a view showing an electromagnet block and an armature block in an electromagnetic relay according to a second embodiment of the invention as seen from the front and the right. With reference to

FIG. 10

, the second embodiment will be described below.

The electromagnetic relay comprises a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, a card

15

and a device body

16

in almost the same manner as those in the first embodiment, and furthermore, comprises an armature block

34

differently from the first embodiment. Each groove

161

f

of a body

161

is provided in a position corresponding to a protrusion

341

b

of a permanent magnet

341

to be fitted in the groove

161

f

, which will be described below.

As shown in

FIG. 10

, the armature block

34

is constituted by the same armature

142

as that in the first embodiment and a permanent magnet

341

and a hinge spring

344

which are different from those in the first embodiment.

The permanent magnet

341

is formed like a plate to have a slightly smaller vertical length than that between the ends

131

a

of the yoke

131

, and includes a protrusion

341

a

serving to fix the hinge spring

344

and protruded toward the center of each of the front and rear side walls, and a pair of protrusions

341

b

serving to fix the permanent magnet

341

to a body

161

of the device body

16

and protruded between both end sides of the rear side wall, and is provided such that a right face is on a level with the right end faces of both ends

131

a

of the yoke

131

. Moreover, the permanent magnet

341

is polarized such that an upper end, a central portion and a lower end are set to have S, N and S poles or N, S and N poles before/after the assembly of the electromagnetic relay, respectively.

The hinge spring

344

serves to fix the permanent magnet

341

and the armature

142

integrally and is formed of a thin metallic plate having elasticity, and has a central portion

144

a

in the same manner as that in the first embodiment. In addition, the hinge spring

344

has both side portions

344

b

extended toward the left from the front and rear ends of the central portion

144

a

and attached to both side faces of the permanent magnet

341

in a longitudinal direction differently from the first embodiment. Moreover, each side portion

344

b

is provided with a hole

344

e

in which the protrusion

341

a

of the permanent magnet

341

is to be fitted.

The procedure for assembling the armature block

34

will be described. First of all, the corresponding shaft portion

142

c

of the armature

142

is inserted into the hole

144

d

of the hinge spring

344

. Subsequently, the tip side of the shaft portion

142

c

is caulked. Consequently, the armature

142

and the hinge spring

344

are fastened to each other. Then, the corresponding protrusion

341

a

of the permanent magnet

341

is fitted in each hole

344

e

of the hinge spring

344

. Thus, it is possible to obtain the armature block

34

having the permanent magnet

341

and the armature

142

fixed integrally with the hinge spring

344

.

The electromagnetic relay having such a structure is assembled in the same procedure as that in the first embodiment. Also in the electromagnetic relay, moreover, the position of the armature

142

is determined by two points of the protrusion

142

b

and either of the positions of a magnet pole. Therefore, an unnecessary clearance is not generated so that a magnetic gap is not caused. Consequently, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

Furthermore, an auxiliary yoke is not used. Therefore, the number of parts is decreased and a size can be reduced still more.

Third Embodiment

FIG. 11

is a view showing an electromagnet block and an armature block in an electromagnetic relay according to a third embodiment of the invention as seen from the front and the right, and

FIG. 12

is a view showing a hinge spring of

FIG. 11

see from the front and the right. With reference to these drawings, the third embodiment will be described below. In FIG.

11

(

a

), E denotes a center of rotation.

The electromagnetic relay comprises a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, a card

15

and a device body

16

in the same manner as those in the first embodiment, and furthermore, an armature block

44

differently from the first embodiment.

As shown in

FIG. 11

, the armature block

44

is constituted by the same permanent magnet

141

and auxiliary yoke

143

as those in the first embodiment and an armature

442

and a hinge spring

444

differently from those in the first embodiment.

The armature

442

is formed like a plate having a greater vertical length than that between both ends

131

a

of a yoke

131

and has protrusions

142

a

and

142

b

in the same manner as those in the first embodiment. In addition, the armature

442

has a pair of shaft portions

442

c

for rivet fastening which are protruded toward the upper and lower sides on the left face differently from the first embodiment, and is provided on the right side with respect to the permanent magnet

141

.

The hinge spring

444

has a central portion

444

a

which serves to fix the permanent magnet

141

, the armature

442

and the auxiliary yoke

143

integrally, is formed of a thin metallic plate having elasticity, is formed like a cross extended in longitudinal and vertical directions and is attached to the left face of the armature

442

, and both side T-shaped portions

444

b

extended toward the left from the front and rear ends of the central portion

444

a

and attached to the front and rear side faces of the auxiliary yoke

143

as shown in FIG.

12

. Moreover, a hole

444

d

in which the shaft portion

442

c

of the armature

442

is to be inserted is formed in each portion extended in the vertical direction of the central portion

444

a

. Furthermore, a hole

444

e

in which the protrusion

143

a

of the auxiliary yoke

143

is to be fitted is formed in each side portion

444

b

. In addition, a protruded piece

444

f

for preventing the vertical movement of the permanent magnet

141

is formed on the upper and lower ends of the side portion

444

b.

The procedure for assembling the armature block

44

will be described. First of all, the corresponding shaft portion

442

c

of the armature

442

is inserted into the hole

444

d

of the hinge spring

444

. Subsequently, the tip side of the shaft portion

442

c

is caulked. Consequently, the armature

442

and the hinge spring

444

are fastened to each other. Then, the permanent magnet

141

is interposed between both side portions

444

b

and the corresponding protrusion

143

a

of the auxiliary yoke

143

is thereafter fitted in the hole

444

e

of the hinge spring

444

. Consequently, it is possible to obtain the armature block

44

having the permanent magnet

141

, the armature

442

and the auxiliary yoke

143

fixed integrally with the hinge spring

444

.

The electromagnetic relay having such a structure is assembled in the same procedure as that in the first embodiment. Also in the electromagnetic relay, moreover, the position of the armature

442

is determined by two points of the protrusion

142

b

and either of the positions of a magnet pole. Therefore, an unnecessary clearance is not generated so that a magnetic gap is not caused. Consequently, a fluctuation in a magnetic characteristic is reduced so that a shock resistance can be enhanced. Moreover, a sensitivity can be regulated easily.

Furthermore, it is possible to suitably prevent wear from being caused by the toggle motion of the armature block

44

. In the first embodiment, the hinge spring

144

is twisted in the twisted portion D as shown in FIG.

7

. Consequently, the rotational motion of the armature

142

is generated. However, since the center C of rotation is shifted from the protrusion

142

b

in the height direction (transverse direction), the protrusion

142

b

of the armature

142

carries out a toggle motion on the permanent magnet

141

. Therefore, a great friction is caused between the protrusion

142

b

of the armature

142

and the permanent magnet

141

so that both of them are worn easily. On the other hand, in the third embodiment, the center E of rotation of the armature

442

is rarely shifted from the protrusion

142

b

of the armature

442

in the height direction as shown in FIG.

11

. Therefore, the protrusion

142

b

of the armature

442

carries out a rolling motion on the hinge spring

444

or the permanent magnet

141

. Consequently, smaller frictional force is generated between the protrusion

142

b

of the armature

442

and the hinge spring

444

or permanent magnet

141

so that their wear can be prevented.

Fourth Embodiment

FIG. 13

is a view showing an armature block of an electromagnetic relay according to a fourth embodiment of the present invention, and

FIG. 14

is a view showing an auxiliary yoke of the electromagnetic relay according to the fourth embodiment. With reference to these drawings, the fourth embodiment will be described below. FIGS.

13

(

a

) and

13

(

b

) are views showing the armature block seen from the front and the right respectively, and FIG.

13

(

c

) is a sectional view taken along the line A—A of FIG.

13

(

a

). FIGS.

14

(

a

) and

14

(

b

) are views showing the auxiliary yoke seen from the left and the front respectively, and FIG.

14

(

c

) is a sectional view taken along the line B—B of FIG.

14

(

a

).

The electromagnetic relay according to the fourth embodiment is constituted by a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, an armature block

14

, a card

15

and a device body

16

for accommodating these parts therein in the same manner as the electromagnetic relay described with reference to

FIGS. 4

to

9

except that an auxiliary yoke

143

has a concavo-convex disengagement prevention structure.

More specifically, a hinge spring

144

has a hole

144

e

formed on each of both ends

144

b

, and the auxiliary yoke

143

has a protrusion

143

a

′ to be fitted in each of the holes

144

e

formed on both ends

144

b

. The electromagnetic relay is different from the electromagnetic relay described with reference to

FIGS. 4

to

9

in that the protrusion

143

a

′ is bent to the left as the disengagement prevention structure.

With such a disengagement prevention structure, the protrusion

143

a

′ bent to the left engages the peripheral portion of the hole

144

e

of the hinge spring

144

as shown in FIG.

14

(

c

) even if a longitudinal vibration or impact is applied to the electromagnetic relay. Therefore, the protrusion

143

a

′ slips off from the hole

144

e

of the hinge spring

144

with difficulty. Consequently, it is possible to provide an electromagnetic relay which changes a characteristic with difficulty even if the vibration or impact is applied.

Fifth Embodiment

FIG. 15

is a view showing an auxiliary yoke of an electromagnetic relay according to a fifth embodiment of the invention, and

FIG. 4

is a view showing an armature block of the electromagnetic relay according to the second embodiment. With reference to these drawings, the fifth embodiment will be described below. FIGS.

15

(

a

) and

15

(

b

) are views showing the auxiliary yoke seen from the left and the front respectively, and FIG.

15

(

c

) is a sectional view taken along the line C—C of FIG.

15

(

a

). FIGS.

16

(

a

) and

16

(

b

) are views showing the armature block seen from the front and the right respectively, and FIG.

16

(

c

) is a sectional view taken along the line D—D of FIG.

16

(

a

).

The electromagnetic relay according to the fifth embodiment is constituted by a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, an armature block

14

, a card

15

and a device body

16

for accommodating these parts therein in the same manner as the electromagnetic relay described with reference to

FIGS. 4

to

9

except that an auxiliary yoke

143

has a concavo-convex disengagement prevention structure.

More specifically, a hinge spring

144

has a hole

144

e

formed on each of both ends

144

b

, and the auxiliary yoke

143

has a protrusion

143

a

to be fitted in each of the holes

144

e

formed on both ends

144

b

. The electromagnetic relay is different from the electromagnetic relay described with reference to

FIGS. 4

to

9

in that the protrusion

143

a

has a V-shaped groove

143

d

for fitting the peripheral portion of the corresponding hole

144

e

of the ends

144

b

provided on the left surface as the disengagement prevention structure.

With such a disengagement prevention structure, the peripheral portion of the corresponding hole

144

e

is fitted in the V-shaped groove

143

d

as shown in FIG.

16

(

c

) even if a longitudinal vibration or impact is applied to the electromagnetic relay. Therefore, the protrusion

143

a

slips off from the hole

144

e

of the hinge spring

144

with difficulty. Consequently, it is possible to provide an electromagnetic relay which changes a characteristic with difficulty even if the vibration or impact is applied. Moreover, since the V-shaped groove

143

d

has a greater angle of a slant face than that of the protrusion

143

a

′ according to the fourth embodiment, it is possible to expect the disengagement prevention effect which is more suitable than that of the fourth embodiment.

Sixth Embodiment

FIG. 17

is a view showing an auxiliary yoke of an electromagnetic relay according to a sixth embodiment of the invention, and

FIG. 18

is a view showing an armature block of the electromagnetic relay according to the six embodiment. With reference to these drawings, the sixth embodiment will be described below. FIGS.

17

(

a

) and

17

(

b

) are views showing the auxiliary yoke seen from the left and the front respectively, and FIG.

17

(

c

) is a sectional view taken along the line E—E of FIG.

17

(

a

). FIGS.

18

(

a

) and

18

(

b

) are views showing the armature block seen from the front and the right respectively, and FIG.

18

(

c

) is a sectional view taken along the line F—F of FIG.

18

(

a

).

The electromagnetic relay according to the six embodiment is constituted by a fixed contact spring block

11

, a moving contact spring block

12

, an electromagnet block

13

, an armature block

14

, a card

15

and a device body

16

for accommodating these parts therein in the same manner as the electromagnetic relay described with reference to

FIGS. 4

to

9

except that an auxiliary yoke

143

has a concavo-convex disengagement prevention structure.

More specifically, a hinge spring

144

has a hole

144

e

formed on each of both ends

144

b

, and the auxiliary yoke

143

has a protrusion

143

a

to be fitted in each of the holes

144

e

formed on both ends

144

b

. The electromagnetic relay is different from the electromagnetic relay described with reference to

FIGS. 4

to

9

in that the protrusion

143

a

has a hook-shaped click portion

143

e

extended to the left as the disengagement prevention structure.

With such an disengagement prevention structure, the click portion

143

e

provided on each protrusion

143

a

engages the peripheral portion of the hole

144

e

of the hinge spring

144

as shown in FIG.

18

(

c

) even if a longitudinal vibration or impact is applied to the electromagnetic relay. Therefore, the protrusion

143

a

slips off from the hole

144

e

of the hinge spring

144

with difficulty. Consequently, it is possible to provide an electromagnetic relay which changes a characteristic with difficulty even if the vibration or impact is applied.

Seventh Embodiment

The electromagnetic relay comprises an electromagnet block

13

, a card

15

and a device body

16

in the same manner as those in the first embodiment, and furthermore, a fixed contact spring block

11

′, a moving contact spring block

12

′ differently from the first embodiment.

The reference numeral

121

′ denotes a movable terminal formed of a metal material to be plate-shaped. A base end of a movable spring

122

′ which will be described below is caulked and fixed to the tip portion in the longitudinal direction. The movable terminal

121

′ has an arm-shaped pressing portion

8

a

extended from one of sides of the tip portion in the longitudinal direction such that it is positioned in the vicinity of the movable spring

122

′. A tip portion of the pressing portion

8

a

can press the movable spring

122

′ to be elastically deformed in a direction of displacement. The pressing portion

8

a

is almost arcuate such that a middle potion keeps away from the movable spring

122

′ and a pressing face of the tip portion for pressing the movable spring

122

′ is curved.

The reference numeral

122

′ denotes a movable spring formed of a metal material like an almost rectangular thin plate. The movable spring

122

′ has a base end caulked and fixed to the tip portion of the movable terminal

121

′ and constitutes a movable terminal block

12

′ together with the movable terminal

121

′. A tip of the movable spring

122

′ is provided with an insertion portion

122

a

′ to be inserted in an insertion hole

15

a

of a card

15

which will be described below, and a moving contact

123

′ is caulked into a tip portion slightly closer to a central part than the tip.

One of sides which is close to the moving contact

123

′ of the movable spring

122

′ acts as a pressed portion

9

c

capable of being pressed by the pressing portion

8

a

of the movable terminal

121

′. A slit-shaped cut portion

9

d

is provided between the pressed portion

9

c

and the moving contact

123

′. The cut portion

9

d

causes the spring force of the pressed portion

9

c

to be locally reduced. Furthermore, when the pressed portion

9

c

is raised and bent, it is elastically deformed in the direction of the displacement of the movable spring

122

′. The pressed portion

9

c

of the movable spring

122

′ is placed in the outermost position together with the pressing portion

8

a

of the movable terminal

121

′ as shown in

FIG. 20

in a state in which the movable terminal block

12

′ is provided on a body

161

to be described below.

The reference numeral

111

′ denotes a fixed terminal formed of a metal material to be plate-shaped. A base end of a fixed contact plate

112

′ which will be described below is caulked and fixed into a tip portion in a longitudinal direction. The fixed terminal

111

′ has a contact portion

10

a

from one of sides of the tip portion in the longitudinal direction such that the tip portion is positioned in the vicinity of a fixed contact

11

b

of the fixed contact plate

11

in the same manner as the movable terminal

121

′ having the arm-shaped pressing portion

8

a

extended. The contact portion

10

a

has a tip portion in contact with the fixed contact plate

112

′. The contact portion

10

a

has the same shape as that of the pressing portion

8

a

, that is, an almost arcuate arm shape to cause a middle portion to be kept away from the fixed contact plate

112

′, and a contact face of the tip portion coming in contact with the vicinity of the fixed contact

11

b

of the fixed contact plate

112

′ is curved.

The contact portion

10

a

has another function such that when a short-circuit is generated, a short-circuit current of several hundreds amperes instantaneously flows to a contact of a relay and a spring. At this time, electromagnetic force (which is proportional to a square of the short-circuit current) acts on the contact and the spring in such a direction as to separate the contact as shown in FIG.

26

(

b

) (this force is referred to as electromagnetic repulsion). If a contact portion

10

a

serving as a shunt plate is provided, the following effects can be obtained.

Since a movable contact

123

′ and a fixed contact

11

b

are interposed between a card

15

and the contact portion

10

a

(shunt plate) through the spring, greater electromagnetic repulsion can be suppressed in the contact portion.

Since a current flowing to a fixed contact plate

112

′ shunts to the contact portion

10

a

(shunt plate) and is decreased, the electromagnetic repulsion to the spring can be reduced.

The fixed terminal

111

′ has the same shape as that of the movable terminal

121

′ except that the base end side is bent. Before bending, the fixed terminal

111

′ has a compatibility with the movable terminal

121

′. Therefore, parts can be shared.

The reference numeral

112

′ denotes a fixed contact plate formed of a metal material like an almost rectangular thin plate with elasticity. The fixed contact plate

112

′ has a base end caulked and fixed into the tip portion of the fixed terminal

111

′ and constitutes a fixed terminal block

11

′ together with the fixed terminal

111

′. The fixed contact plate

112

′ has a pressed portion

11

a

extended from one of sides and a fixed contact

11

b

caulked into a tip portion. The pressed portion

11

a

is pressed from a prepressure rib portion

1001

positioned at the inner side face of the body

161

to be described below as reaction of spring force of the fixed contact plate

112

′ itself. The fixed contact plate

112

′ has a spring load in the direction of the displacement of the movable spring

122

′ by pressing the pressed portion

11

a

from the inner side face of the body

161

. Thus, prepressures of the contacts

123

′ and

11

b

are obtained.

AS shown in FIG.

27

(

b

), the fixed contact plate

112

′ is preliminarily bent from a base toward the left side (moving contact side. When a fixed contact spring block

12

′ is incorporated into the body

161

, the fixed contact plate

112

′ is set to a predetermined position (as shown in FIG.

27

(

a

) through a prepressure rib portion

1001

for a prepressure.

If the pressed portion

11

a

for a prepressure is not provided, in this case, the fixed contact plate

112

′ is not bent differently from that in FIG.

27

(

b

).

FIG.

27

(

c

) shows a relationship between a contact position and a contact pressure which is obtained with or without application of the prepresssure. In the case in which the prepressure is applied, a great contact pressure is generated immediately after the contact. Therefore, it is possible to reduce the maintenance of an unstable contact state in which a small contact pressure is generated.

The reference numeral

15

denotes a card formed of a non-conductive material such as plastics to have a rectangular plate shape, for example, and has an insertion hole

12

a

for insertion in an insertion portion

142

c

of the armature

4

provided on one of ends in a longitudinal direction thereof and an insertion hole

15

a

for insertion in an insertion portion

122

a

′ of the movable spring

122

provided on the other end. Thus, the card

15

links the armature

4

and the movable spring

122

′ by inserting the insertion portion

142

c

of the armature

4

in the insertion hole

15

b

and inserting the insertion portion

122

a

′ of the movable spring

122

′ in the insertion hole

15

a.

The reference numeral

161

denotes a body formed of plastics to have an almost box shape having one of sides opened, for example, and is provided with the above-mentioned parts. In the state of the provision, the movable terminal

121

′ and the fixed terminal

111

′ are protruded outward and the coil terminal

134

fixedly penetrating through the body

161

is also protruded outward. The coil terminal

134

is connected to the coil

13

.

Next, description will be given to the sensitivity regulation of the abutting and separating operation of both contacts

122

′ and

11

b

. In the case in which a sensitivity is to be increased, the arm-shaped pressing portion

8

a

of the movable terminal

121

′ is more bent and plastic deformed toward the movable spring

122

′ side as compared with the present conditions, thereby increasing the pressing force of the pressing portion

8

a

against the pressed portion

9

c

and the movable spring

122

′ is elastically deformed toward the fixed contact plate

112

′ in the direction of the displacement thereof, thereby reducing an opposed distance between both contacts

123

′ and

11

b

. At this time, if the pressed portion

9

c

of the movable spring

122

′ is raised and elastically deformed toward the pressing portion

8

a

in the direction of the displacement the pressing force of the pressing portion

8

a

against the pressed portion

9

c

of the movable spring

122

′ is more increased. Consequently, the amount of elastic deformation of the whole movable spring

122

′ is more increased. Thus, the sensitivity can be more increased.

To the contrary, if the sensitivity is to be reduced, the arm-shaped pressing portion

8

a

of the movable terminal

121

′ is bent and elastically deformed toward the opposite side of the movable spring

122

′ as compared with the present conditions, thereby reducing the pressing force of the pressing portion

8

a

against the pressed portion

9

c

to more increase the opposed distance between the contacts

123

′ and

11

b

. At this time, if the pressed portion

9

c

of the movable spring

122

′ is raised and elastically deformed in such a direction as to go away from the pressing portion

8

a

in the direction of the displacement, the pressing force of the pressing portion

8

a

against the pressed portion

9

c

of the movable spring

122

′ is more reduced so that the amount of elastic deformation of the whole movable spring is more decreased. Therefore, the sensitivity can be more reduced.

Next, the operation will be described. When a current is caused to flow in a preset direction so that the coil

13

is excited, the other end of the armature

4

is attracted into the magnetic pole portion on the other end of the yoke

1

such that a closed magnetic circuit is formed. Consequently, the armature

4

is rotated clockwise in

FIG. 19

by using the central piece of the hinge spring

144

as a rotating fulcrum. As a result, the card

15

linked to the armature

4

is driven toward the movable spring

122

′, and the movable spring

122

′ linked to the driven card

15

is displaced toward the fixed contact plate

112

′ so that the moving contact

123

′ of the movable spring

122

′ abuts on the fixed contact

11

b

of the fixed contact plate

112

′. Consequently, the state shown in FIG.

26

(

a

) is obtained. When the excitation of the coil

13

is stopped, this state is held.

When a current is caused to flow in a direction reverse to the above-mentioned direction so that the coil

13

is excited in this state, one of the ends of the armature

4

is attracted into the magnetic pole portion on one of the ends of the yoke

1

such that a closed magnetic circuit is formed. Consequently, the armature

4

is rotated counterclockwise in

FIG. 26

by using the central piece of the hinge spring

144

as a rotating fulcrum. As a result, the card

15

linked to the armature

142

is driven in such a direction as to go away from the movable spring

122

′, and the movable spring

122

′ linked to the driven card

15

is displaced apart from the fixed contact plate

112

′ so that the moving contact

123

′ of the movable spring

122

′ is separated from the fixed contact

11

b

of the fixed contact plate

112

′. When the excitation of the coil

13

is stopped, this state is held.

In such an electromagnetic relay, if the opposed distance between the contacts

123

and

11

b

is adjusted to be smaller by the elastic deformation of the movable spring

122

in the direction of the displacement, the sensitivity of the abutting and separating operation of the contacts

123

and

11

b

is increased. To the contrary, if the opposed distance between the contacts

123

′ and

11

b

is adjusted to be longer, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

is reduced. Thus, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

can be regulated. Thus, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

is regulated by the elastic deformation of the movable spring

122

′ in the direction of the displacement. Therefore it is not necessary to provide a clearance for sensitivity regulation between the magnetic pole portions of the yoke

1

and the armature

4

. Consequently, suction force is not varied so that the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

can be regulated easily.

Moreover, the movable spring

122

′ is elastically deformed by the pressing portion

8

a

in the direction of the displacement. Therefore, the amount of elastic deformation can be regulated by increasing or reducing the pressing force of the pressing portion

8

a

. Furthermore, the sensitivity of the abutting and separating operation of the contacts

122

a

′ and

11

a

can be regulated easily.

Furthermore, the pressing portion

8

a

is provided on the movable terminal

121

′ itself. Therefore, it is not necessary to provide the pressing portion

8

a

on the body

161

, for example, by particularly paying attention such that the pressing portion

8

a

does not abut on the movable terminal

121

′ to cause a mutual interference. Thus, assembly can be carried out easily.

Moreover, the spring force of the pressed portion

9

c

of the movable spring

122

′ is locally reduced. Therefore, the whole movable spring

122

′ can be slightly elastically deformed in the direction of the displacement. Consequently, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

can be regulated with high precision.

Furthermore, the press state of the pressing portion

8

a

can be adjusted by elastically deforming the pressed portion

9

c

of the movable spring

122

′ in the direction of the displacement. Therefore, the elastic deformation can be slightly adjusted in the direction of the displacement. Thus, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

can be regulated with high precision.

Moreover, the current also flows to the contact portion

10

a

extended from the fixed terminal

111

′ as well as the fixed contact plate

11

when the contacts

123

′ and

11

b

abut. Therefore, the current flowing to the fixed contact plate

112

′ can be reduced so that heat generation can be suppressed. In addition, the contact portion

10

a

is not in contact with the base end of the fixed contact plate

112

′ but the vicinity of the fixed contact

11

b

and constitutes a parallel circuit together with the fixed contact plate

112

over the almost whole fixed contact plate

112

in a longitudinal direction thereof. Consequently, it is possible to enhance the effect of suppressing the heat generation of the fixed contact plate

112

.

Furthermore, when the contact portion

10

a

extended from the fixed terminal

111

is elastically deformed in the direction of the displacement of the movable spring

122

′ to shift a contact position and the fixed contact plate

112

′ is thus elastically deformed in the direction of the displacement of the movable spring

122

′, the opposed distance between the contacts

123

′ and

11

b

can be regulated. Consequently, it is also possible to regulate the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b.

Moreover, the fixed contact plate

112

′ comes in contact with the contact portion

10

a

of the fixed terminal

111

′ on the opposite side of the moving contact

123

′ during the abutment of the contacts. Therefore, a contact bounce can be decreased.

Furthermore, the fixed contact plate

112

′ obtains the prepressures of the contacts

123

′ and

11

b

. Therefore, a contact pressure can be obtained through the abutment of the contacts

123

′ and

11

b.

Moreover, in a state in which the movable terminal block

12

′ is provided on the body

161

, the pressed portion

9

c

of the movable spring

122

′ and the pressing portion

8

a

of the movable terminal

121

′ are placed in outermost positions as shown in FIG.

20

. Therefore, it is possible to easily carry out a deforming work for regulating the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b.

Furthermore, both the pressing portion

8

a

of the movable terminal

121

and the contact portion

10

a

of the fixed terminal

111

′ are almost arcuate arm-shaped. Therefore, it is possible to easily carry out elastically deformation in the direction of the displacement of the movable spring

122

′.

Moreover, both the pressing surface of the pressing portion

8

a

of the movable terminal

121

′ and the contact surface of the contact portion

10

a

of the fixed terminal

111

′ are curved. Therefore, the movable spring

122

′ and the fixed contact plate

111

′ are worn with difficulty so that metal powder is generated with difficulty. Consequently, the metal powder is rarely stuck to the contacts

123

′ and

11

b

so that contact failures are caused with difficulty.

While the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

is regulated by the elastic deformation of the pressing portion

8

a

of the movable terminal

121

′ and the pressed portion

9

c

of the movable spring

122

′ in the present embodiment, the sensitivity can also be regulated by the elastic deformation of one of them.

Although the fixed contact plate

112

′ has elasticity in the present embodiment, the sensitivity of the abutting and separating operation of the contacts

123

′ and

11

b

can be regulated by the elastic deformation of the movable spring

122

′ in the direction of the displacement even if the fixed contact plate

112

′ does not have the elasticity.

While the cut portion

9

d

is provided on the movable spring

122

′ to locally reduce the spring force of the pressed portion

9

c

in the present embodiment, the movable spring

122

′ having no cut portion

9

d

may be used as shown in

FIG. 28

if the sensitivity does not need to be regulated slightly, for example.

Although the slit-shaped cut portion

9

d

of the movable spring

122

′ is provided and the pressed portion

9

c

can be raised and elastically deformed in the present embodiment, the movable spring

122

′ having a simply notch-shaped cut portion

9

d

may be used as shown in

FIG. 29

if the sensitivity does not need to be regulated slightly, for example.

While a polarized relay including the permanent magnet

7

is used in the present embodiment, a so-called non-polarized relay including no permanent magnet

7

can obtain the same effects.

Number	Date	Country	Kind
11-304734	Oct 1999	JP
11-322700	Nov 1999	JP

Number	Name	Date	Kind
4703293	Ono et al.	Oct 1987	A
5515019	Schedele	May 1996	A

Electromagnetic relay

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

Priority Claims (2)

US Referenced Citations (2)