Electromagnetic relay

Abstract

This electromagnetic relay includes a fixed contact, a movable contact piece, a base, a coil block, and a movable block. The movable contact piece includes a movable contact facing the fixed contact. The movable contact piece is movable between an open position where the movable contact is separated from the fixed contact and a closed position where the movable contact contacts the fixed contact. The coil block includes a coil and an iron core including a first attraction part. The movable block moves the movable contact piece between the open position and the closed position. The movable block includes an armature, a card, and an urging member. The armature is rotated by being attracted to the first attraction part of the iron core by the electromagnetic force of the coil. The card moves the movable contact piece to the closed position in accordance with the rotation of the armature. The urging member contacts the base or the coil block when the movable contact piece is in the open position, and generates an urging force in a direction toward the first attraction part with respect to the armature.

Description

electromagnetic relay

[0001] The present invention relates to an electromagnetic relay.

[0002] Electromagnetic relays are used to switch high-frequency signals. The electromagnetic relays disclosed in Patent Documents 1 and 2 include a movable contact piece, a fixed terminal, a movable block, and an electromagnet block. The electromagnet block includes a coil and generates an electromagnetic force that operates the movable block. The movable block presses the movable contact piece, causing the movable contact piece to contact the fixed terminal. The electromagnetic relay is mounted on a printed circuit board.

[0003] JP 2003-51234 A JP 2017-168249 A

[0004] In electromagnetic relays such as those described above, the spring load characteristics may be adjusted by bending the movable contact piece in order to adjust the operating voltage. However, in high-frequency relays such as those described in Patent Document 1, the movable contact piece is hidden by a structure, making bending difficult. Furthermore, both ends of the movable contact piece are free, making bending difficult. In high-frequency relays such as those described in Patent Document 2, bending is possible, but bending the movable contact piece may cause the impedance to deviate from the design value, resulting in a deterioration of high-frequency characteristics. An object of the present invention is to provide an electromagnetic relay that can suppress deterioration of high-frequency characteristics.

[0005] An electromagnetic relay according to one aspect of the present invention comprises a fixed contact, a movable contact piece, a base, a coil block, and a movable block. The movable contact piece includes a movable contact facing the fixed contact. The movable contact piece is movable between an open position in which the movable contact is separated from the fixed contact and a closed position in which the movable contact is in contact with the fixed contact. The coil block is disposed on the base. The coil block includes a coil and an iron core including a first attraction portion. The movable block moves the movable contact piece between the open position and the closed position. The movable block includes an armature, a card, and a biasing member. The armature rotates when attracted to the first attraction portion of the iron core by the electromagnetic force of the coil. The card moves the movable contact piece to the closed position in response to the rotation of the armature. The biasing member contacts the base or the coil block when the movable contact piece is in the open position, generating a biasing force on the armature in a direction toward the first attraction portion.

[0006] In the electromagnetic relay according to this aspect, the movable block includes a biasing member that contacts the base when the movable contact piece is in the open position and generates a biasing force on the armature in a direction toward the first attraction portion. Therefore, the spring load characteristics can be adjusted by adjusting the biasing force of the biasing member to adjust the operating voltage. This reduces deviation of the impedance value from the design value compared to adjusting the spring load characteristics by bending the movable contact piece. As a result, deterioration of the high-frequency characteristics can be suppressed.

[0007] The biasing member may be spaced apart from the base when the movable contact piece is in the closed position, which makes it easier to adjust the operating voltage.

[0008] The electromagnetic relay may further include a permanent magnet. The iron core may further include a second attraction portion. The armature may include a first end attracted to the first attraction portion by the electromagnetic force of the coil, and a second end attracted to the second attraction portion by the magnetic force of the permanent magnet.

[0009] The base may include an opening facing the biasing member, and the biasing member may include a free end visible through the opening. In this case, for example, the biasing force of the biasing member can be adjusted by inserting an adjustment tool through the opening.

[0010] The card may be disposed above the movable contact piece. The armature may be disposed above the card. The biasing member may be disposed above the lower end of the armature. In this case, for example, the biasing member is disposed at a position away from the transmission path, thereby preventing deterioration of high-frequency characteristics.

[0011] The movable block may further include an insulating member that supports the armature and the biasing member. In this case, the armature and the biasing member move integrally with the insulating member, making it easier to adjust the operating voltage.

[0012] The movable block may further include a hinge spring that functions as a rotation axis of the insulating member. The hinge spring may be integral with the biasing member and may protrude from the insulating member in a first direction. The biasing member may protrude from the insulating member in a second direction intersecting the first direction. In this case, for example, the hinge spring and the biasing member may be configured by a single leaf spring.

[0013] The electromagnetic relay may further include a transmission line base disposed below the movable contact piece. The movable block may be disposed above the movable contact piece. In this case, the biasing member is disposed at a position away from the transmission line base, thereby preventing deterioration of high-frequency characteristics.

[0014] The electromagnetic relay may further include a shield plate disposed above the movable contact. The biasing member may be disposed above the shield plate. In this case, the shield plate can suppress deterioration of high frequency characteristics. Furthermore, since the biasing member is disposed at a position farther from the transmission line base than the shield plate, deterioration of high frequency characteristics can be further suppressed.

[0015] The biasing member does not have to overlap with the movable contact piece when viewed from above. In this case, for example, when the movable contact piece forms part of a transmission path for transmitting an RF signal, deterioration of high-frequency characteristics can be suppressed compared to when the biasing member overlaps with the movable contact piece when viewed from above.

[0016] According to the present invention, it is possible to provide an electromagnetic relay that can suppress deterioration of high frequency characteristics.

[0017] 1 is a perspective view of an electromagnetic relay; 2 is a perspective view of an electromagnetic relay; 3 is an exploded perspective view of an electromagnetic relay; 4 is a perspective view of a transmission line base; 5 is a top view of the transmission line base; 6 is a perspective view of a base assembly and a stand as seen from below; 7 is a perspective view of a base assembly as seen from below; 8 is an exploded perspective view of a base assembly; 9 is a cross-sectional view of an electromagnetic relay in an open state; 10 is a cross-sectional view of an electromagnetic relay in a closed state; 11 is a perspective view of a movable block; 12 is a side view of an electromagnetic relay in an open state; 13 is a side view of an electromagnetic relay in a closed state;

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic relay according to an embodiment will now be described with reference to the drawings. The electromagnetic relay according to the present embodiment is used to switch between a high frequency RF signal and a low frequency DC signal.

[0019] 1 and 2 are perspective views of an electromagnetic relay 1 according to an embodiment. As shown in Fig. 1 and 2, the electromagnetic relay 1 includes a case 2, a transmission line base 3, a base assembly 4, and a stand 5. Note that the case 2 is omitted in Fig. 2. In the following description, the direction in which the base assembly 4 and the stand 5 are arranged relative to the transmission line base 3 is defined as "upward," and the opposite direction is defined as "downward."

[0020] As shown in Fig. 1, the case 2 is attached to the transmission line base 3. The case 2 covers the upper surface of the transmission line base 3, the base assembly 4, and the stand 5. Fig. 3 is an exploded perspective view of the electromagnetic relay 1. As shown in Fig. 3, the electromagnetic relay 1 includes a first movable contact piece 6A, a second movable contact piece 6B, and a shield plate 7. The first movable contact piece 6A, the second movable contact piece 6B, and the shield plate 7 are arranged on the transmission line base 3.

[0021] FIG. 4 is a perspective view of the transmission line base 3. Note that the shield plate 7 is omitted in FIG. 4. The transmission line base 3 is a printed circuit board. However, the transmission line base 3 may also be a ceramic substrate, a resin molded product, a metal molded product, an FPC (flexible printed circuit board), or an MID (molded circuit component). As shown in FIG. 4, the transmission line base 3 includes first to fourth conductor layers 11-14 and first to third dielectric layers 15-17. The first to fourth conductor layers 11-14 are made of an electrically conductive material such as copper. The first to third dielectric layers 15-17 are made of a dielectric material. The first to fourth conductor layers 11-14 and the first to third dielectric layers 15-17 are alternately stacked.

[0022] The first conductor layer 11 is provided on the upper surface of the transmission line base 3. Fig. 5 is a top view of the transmission line base 3. Note that the shield plate 7 and the movable contact pieces 6A and 6B are omitted in Fig. 5. As shown in Figs. 4 and 5, the first conductor layer 11 is provided with a first RF line 21A, a second RF line 21B, a first DC line 22A, a second DC line 22B, and a ground line 23.

[0023] The first RF line 21A and the second RF line 21B are transmission lines for transmitting RF signals. The first RF line 21A includes a first transmission line 24A and a second transmission line 25A. The first transmission line 24A and the second transmission line 25A are arranged apart from each other. The first transmission line 24A and the second transmission line 25A are electrically isolated from each other. The first transmission line 24A is connected to a first input terminal 26A. The second transmission line 25A is connected to a first RF terminal 27A. The first input terminal 26A and the first RF terminal 27A are each through-hole terminals provided on an end surface of the transmission line base 3.

[0024] The second RF line 21B includes a third transmission line 24B and a fourth transmission line 25B. The third transmission line 24B and the fourth transmission line 25B are arranged apart from each other. The third transmission line 24B and the fourth transmission line 25B are electrically isolated from each other. The third transmission line 24B is connected to a second input terminal 26B. The fourth transmission line 25B is connected to a second RF terminal 27B. The second input terminal 26B and the second RF terminal 27B are each a through-hole terminal provided on an end surface of the transmission line base 3.

[0025] The first DC line 22A and the second DC line 22B are transmission lines for transmitting DC signals. The first DC line 22A is connected to the first transmission line 24A and the ground line 23. A first inductor 28A and a first capacitor 29A are disposed on the first DC line 22A. Note that in the drawings, only a portion of the first inductor 28A is denoted by the reference numeral 28A, and the reference numerals for the remaining first inductors 28A are omitted.

[0026] The first DC line 22A is connected to a first DC terminal 30A between the first inductor 28A and the first capacitor 29A. The first DC terminal 30A is a through-hole terminal provided on an end surface of the transmission line base 3. The first DC line 22A, the first inductor 28A, and the first capacitor 29A function as a low-pass filter that passes DC signals but blocks RF signals. The first inductor 28A and the first capacitor 29A are set to block high-frequency signals, for example, of 1 kHz or higher.

[0027] The second DC line 22B is connected to the third transmission line 24B and the ground line 23. A second inductor 28B and a second capacitor 29B are arranged on the second DC line 22B. Note that in the drawing, only a portion of the second inductor 28B is denoted by the reference numeral 28B, and the reference numerals for the remaining second inductors 28B are omitted.

[0028] The second DC line 22B is connected to a second DC terminal 30B between the second inductor 28B and the second capacitor 29B. The second DC terminal 30B is a through-hole terminal provided on an end surface of the transmission line base 3. The second DC line 22B, the second inductor 28B, and the second capacitor 29B function as a low-pass filter that passes DC signals but blocks RF signals. The second inductor 28B and the second capacitor 29B are set to block high-frequency signals, for example, of 1 kHz or higher.

[0029] The second to fourth conductor layers 12-14 are ground layers. The second conductor layer 12 is disposed below the first conductor layer 11. The second conductor layer 12 is stacked on the first conductor layer 11 with a first dielectric layer 15 interposed therebetween. The third conductor layer 13 is stacked on the second conductor layer 12 with a second dielectric layer 16 interposed therebetween. The fourth conductor layer 14 is stacked on the third conductor layer 13 with a third dielectric layer 17 interposed therebetween.

[0030] A plurality of through-hole terminals 31 are provided on an end face of the transmission line base 3. In the drawings, only some of the through-hole terminals 31 are labeled with the reference numeral 31, and the reference numerals of the other through-hole terminals 31 are omitted. The through-hole terminals 31 connect the above-described ground line 23 to the second to fourth conductor layers 12-14.

[0031] 4, the first movable contact piece 6A and the second movable contact piece 6B are arranged on the transmission line base 3. The first movable contact piece 6A and the second movable contact piece 6B are arranged above the first conductor layer 11. The first movable contact piece 6A extends linearly between the first transmission line 24A and the second transmission line 25A. The first movable contact piece 6A is arranged above the first RF line 21A.

[0032] The first movable contact piece 6A includes a first joint portion 32A, a first contact portion 33A (an example of a movable contact), and a first intermediate portion 34A. The first joint portion 32A is a fixed end. The first joint portion 32A is joined to the first transmission line 24A. The first joint portion 32A is joined to the first transmission line 24A by joining means such as welding or soldering. The first contact portion 33A is a free end. The first contact portion 33A is disposed above the second transmission line 25A. The first intermediate portion 34A is located between the first joint portion 32A and the first contact portion 33A. The first intermediate portion 34A extends in a substantially linear manner parallel to the first transmission line 24A and the second transmission line 25A. The first contact portion 33A has a single-break structure.

[0033] As described below, the first movable contact piece 6A is movable between a closed position and an open position. When the first movable contact piece 6A is in the closed position, the first contact portion 33A contacts the second transmission line 25A. This causes the first movable contact piece 6A to connect the first transmission line 24A and the second transmission line 25A. When the first movable contact piece 6A is in the open position, the first contact portion 33A separates from the second transmission line 25A. This causes the first movable contact piece 6A to disconnect the first transmission line 24A and the second transmission line 25A. The first contact portion 33A faces a portion of the second transmission line 25A. In this embodiment, the portion of the second transmission line 25A facing the first contact portion 33A is an example of a fixed contact.

[0034] The second movable contact piece 6B is disposed above the second RF line 21B. The second movable contact piece 6B includes a second joint portion 32B, a second contact portion 33B (an example of a movable contact), and a second intermediate portion 34B. The second joint portion 32B is joined to the third transmission line 24B by joining means such as welding or soldering. The second contact portion 33B is disposed above the fourth transmission line 25B. The second intermediate portion 34B is located between the second joint portion 32B and the second contact portion 33B. The second intermediate portion 34B extends in a substantially straight line parallel to the third transmission line 24B and the fourth transmission line 25B. The second contact portion 33B has a single-break structure.

[0035] Like the first movable contact piece 6A, the second movable contact piece 6B is movable between a closed position and an open position. When the second movable contact piece 6B is in the closed position, the second contact portion 33B contacts the fourth transmission line 25B. This causes the second movable contact piece 6B to connect the third transmission line 24B and the fourth transmission line 25B. When the second movable contact piece 6B is in the open position, the second contact portion 33B separates from the fourth transmission line 25B. This causes the second movable contact piece 6B to disconnect the third transmission line 24B and the fourth transmission line 25B. The second contact portion 33B faces a portion of the fourth transmission line 25B. In this embodiment, the portion of the fourth transmission line 25B facing the second contact portion 33B is an example of a fixed contact.

[0036] The shield plate 7 is disposed on the transmission line base 3. The shield plate 7 is made of a conductive material. The shield plate 7 is disposed above the first contact portion 33A and the second contact portion 33B. The shield plate 7 is connected to the ground line 23. The shield plate 7 improves the isolation characteristics between the first RF line 21A and the second RF line 21B.

[0037] Fig. 6 is a perspective view of the base assembly 4 and the stand 5 as viewed from below. Fig. 7 is a perspective view of the base assembly 4 as viewed from below. Fig. 8 is an exploded perspective view of the base assembly 4. Figs. 9 and 10 are cross-sectional views of the electromagnetic relay 1. As shown in Figs. 6 to 9, the base assembly 4 includes a coil base 40 (an example of a base), a coil block 41, and a movable block 42.

[0038] The coil block 41 is disposed on the coil base 40. The coil block 41 includes a coil 43, a spool 44, and an iron core 45. The coil 43 is wound around the spool 44. The iron core 45 is disposed within the coil 43. The iron core 45 includes an intermediate portion 46, a first attraction portion 47, and a second attraction portion 48. The intermediate portion 46 is disposed within the coil 43 and extends in the axial direction of the coil 43. The first attraction portion 47 protrudes from the coil 43 in the axial direction of the coil 43. The first attraction portion 47 is disposed facing downward. The second attraction portion 48 protrudes from the coil 43 in the opposite direction to the first attraction portion 47 in the axial direction of the coil 43. The second attraction portion 48 is disposed facing downward.

[0039] The movable block 42 is operated by the electromagnetic force of the coil 43 to move the first movable contact piece 6A and the second movable contact piece 6B between the closed position and the open position. Fig. 11 is a perspective view of the movable block 42. As shown in Fig. 11, the movable block 42 includes an iron piece 50 (an example of an armature), a first hinge spring 51, a second hinge spring 52, a permanent magnet 53, a card 54, a movable insulating base 55 (an example of an insulating member), a first biasing member 56, and a second biasing member 57.

[0040] The iron piece 50 is supported by a movable insulating base 55. The iron piece 50 is attracted to the first attraction portion 47 of the iron core 45 by the electromagnetic force of the coil 43, thereby rotating around the first hinge spring 51 and the second hinge spring 52 as a rotation axis. The iron piece 50 is disposed above the card 54. The iron piece 50 includes a first end 501 and a second end 502. The first end 501 protrudes from the movable insulating base 55 in the axial direction of the coil 43. The first end 501 is disposed below the first attraction portion 47 of the iron core 45 and faces the first attraction portion 47. The second end 502 protrudes from the movable insulating base 55 in the opposite direction to the first end 501 in the axial direction of the coil 43. The second end 502 is disposed below the second attraction portion 48 of the iron core 45 and faces the second attraction portion 48.

[0041] The first hinge spring 51 is supported by the movable insulating base 55. The first hinge spring 51 protrudes from the movable insulating base 55 toward one side of the movable insulating base 55. The first hinge spring 51 is integral with a first biasing member 56. The second hinge spring 52 is supported by the movable insulating base 55. The second hinge spring 52 protrudes from the movable insulating base 55 toward the other side of the movable insulating base 55. The second hinge spring 52 is integral with a second biasing member 57. The permanent magnet 53 is attached to the upper surface of the movable insulating base 55.

[0042] The card 54 moves the first movable contact piece 6A and the second movable contact piece 6B to the closed position in response to the rotation of the iron piece 50. The card 54 is supported by the movable insulating base 55. The card 54 protrudes downward from the movable insulating base 55. The card 54 is disposed above the first movable contact piece 6A and the second movable contact piece 6B. More specifically, the card 54 is disposed above the first intermediate portion 34A of the first movable contact piece 6A and the second intermediate portion 34B of the second movable contact piece 6B. The card 54 is connected to the underside of the first end portion 501 of the iron piece 50. The card 54 protrudes downward from the underside of the first end portion 501.

[0043] The movable insulating base 55 is supported so as to be able to swing relative to the coil base 40. As shown in FIG. 8 , the coil base 40 includes support protrusions 58 and 59. As shown in FIG. 10 , the movable insulating base 55 includes support holes 60 and 61. The support protrusions 58 and 59 are disposed in the support holes 60 and 61 and support the movable insulating base 55 so as to be able to swing. Also, as shown in FIG. 8 , the coil base 40 includes a first support recess 62 and a second support recess 63. The first hinge spring 51 is disposed in the first support recess 62. The first hinge spring 51 is connected to the coil base 40 at the first support recess 62. The second hinge spring 52 is disposed in the second support recess 63. The second hinge spring 52 is connected to the coil base 40 at the second support recess 63. The movable insulating base 55 is supported by the coil base 40 so as to be swingable around the first hinge spring 51 and the second hinge spring 52 .

[0044] The first biasing member 56 is supported by the movable insulating base 55. The first biasing member 56 is a leaf spring. The first biasing member 56 is connected to the first hinge spring 51. The first biasing member 56 protrudes from the movable insulating base 55 in a direction different from that of the first hinge spring 51. The first biasing member 56 protrudes from the movable insulating base 55 in the axial direction of the coil 43. The first biasing member 56 is fixed to the movable insulating base 55 by insert molding. The first biasing member 56 is positioned above the lower end of the iron piece 50. The first biasing member 56 is positioned above the second end 502 of the iron piece 50. The first biasing member 56 is positioned above the shield plate 7. When viewed from above, the first biasing member 56 does not overlap with the first movable contact piece 6A and the second transmission line 25A.

[0045] 12 , when the first movable contact piece 6A and the second movable contact piece 6B are in the open position, the first biasing member 56 comes into contact with the coil base 40 and generates a biasing force on the iron piece 50 in a direction toward the first attraction portion 47. When the first movable contact piece 6A and the second movable contact piece 6B are in the open position, the first biasing member 56 generates a biasing force that biases the first end 501 of the iron piece 50 toward the first attraction portion 47.

[0046] 13 , the first biasing member 56 is separated from the coil base 40 when the first movable contact piece 6A and the second movable contact piece 6B are in the closed position. The first biasing member 56 does not apply a biasing force to the card 54 when the first movable contact piece 6A and the second movable contact piece 6B are in the closed position. In other words, the first biasing member 56 does not affect the pressing force with which the card 54 presses the first movable contact piece 6A and the second movable contact piece 6B when the first movable contact piece 6A and the second movable contact piece 6B are in the closed position.

[0047] The coil base 40 includes a first opening 401 that faces the first biasing member 56. The first opening 401 is open in the axial direction of the coil 43. The first biasing member 56 includes a first free end 561 that is visible through the first opening 401 when the case 2 is removed. The first free end 561 includes a pressing protrusion that can come into contact with the coil base 40. The pressing protrusion is located on the top surface of the tip of the first free end 561.

[0048] The second biasing member 57 has a shape symmetrical to the first biasing member 56 with respect to the axis of the coil 43. The second biasing member 57 is disposed above the lower end of the iron piece 50. The second biasing member 57 is disposed above the second end 502 of the iron piece 50. The second biasing member 57 is disposed above the shield plate 7. When viewed from above, the second biasing member 57 does not overlap with the second movable contact piece 6B and the fourth transmission line 25B.

[0049] The second biasing member 57 comes into contact with the coil base 40 when the first movable contact piece 6A and the second movable contact piece 6B are in the open position, and generates a biasing force on the iron piece 50 in a direction toward the first attraction portion 47. The second biasing member 57 has the same function as the first biasing member 56. That is, the second biasing member 57 generates a biasing force that biases the first end 501 of the iron piece 50 toward the first attraction portion 47 when the first movable contact piece 6A and the second movable contact piece 6B are in the open position.

[0050] The coil base 40 includes a second opening 402 that faces the second biasing member 57. The second opening 402 is open in the axial direction of the coil 43. The second biasing member 57 includes a second free end 571 that is visible through the second opening 402 when the case 2 is removed. The second free end 571 includes a pressing protrusion that can come into contact with the coil base 40. The pressing protrusion is located on the top surface of the tip of the second free end 571.

[0051] The stand 5 is disposed above the transmission line base 3 and supports the base assembly 4. More specifically, the stand 5 supports the coil base 40. The coil block 41 is supported by the stand 5 via the coil base 40. The movable block 42 is supported by the stand 5 via the coil base 40. The stand 5 includes a frame 70 and a plurality of legs 71-74. As shown in FIG. 6 , the frame 70 has an opening 75 in its center. The movable block 42 is disposed within the opening 75 of the frame 70. The card 54 extends downward through the opening 75.

[0052] A plurality of legs 71-74 protrude downward from the frame 70. The plurality of legs 71-74 each include a flat bottom surface 76-79. Specifically, the plurality of legs 71-74 includes a first leg 71, a second leg 72, a third leg 73, and a fourth leg 74. The first to fourth legs 71-74 are respectively disposed at corners of the frame 70.

[0053] Next, the operation of the electromagnetic relay 1 will be described. FIG. 9 shows the electromagnetic relay 1 in an open state. As shown in FIG. 9 , when no current flows through the coil 43, the coil 43 is not excited, and the iron piece 50 is not attracted to the iron core 45. Due to the magnetic force of the permanent magnet 53, the second end 502 of the iron piece 50 is attracted to and contacts the second attraction portion 48 of the iron core 45. Therefore, the card 54 is separated from the first movable contact piece 6A and the second movable contact piece 6B, and the first movable contact piece 6A and the second movable contact piece 6B are each in the disconnected position. Therefore, in the first RF line 21A, the first transmission line 24A and the second transmission line 25A are disconnected from each other. In addition, in the second RF line 21B, the third transmission line 24B and the fourth transmission line 25B are disconnected from each other. In the open state, the biasing force of the first biasing member 56 and the second biasing member 57 is set to be smaller than the magnetic force of the permanent magnet 53. In the open position, the first movable contact piece 6A and the second movable contact piece 6B come into contact with the insulating layer 20 arranged on the lower surface of the shield plate 7.

[0054] When current flows through the coil 43, the electromagnetic relay 1 is in the closed state shown in FIG. 10 . When the electromagnetic relay 1 is in the closed state, the electromagnetic force of the coil 43 causes the first end 501 of the iron piece 50 to be attracted to the first attraction portion 47 of the iron core 45 and rise. This causes the iron piece 50 to swing, and the second end 502 to descend. The card 54 descends together with the second end 502 and presses the first movable contact piece 6A and the second movable contact piece 6B, thereby moving the first movable contact piece 6A and the second movable contact piece 6B to their respective connected positions. This connects the first transmission line 24A and the second transmission line 25A to each other in the first RF line 21A. Furthermore, the third transmission line 24B and the fourth transmission line 25B to each other in the second RF line 21B.

[0055] When the current to the coil 43 is interrupted, the spring reaction forces of the first movable contact piece 6A, the second movable contact piece 6B, the first hinge spring 51, and the second hinge spring 52, as well as the magnetic force of the permanent magnet 53, rotate the iron piece 50 in the opposite direction, causing the first end 501 to descend and separate from the first attraction portion 47, and the second end 502 to rise. The card 54 rises together with the second end 502 and separates from the first movable contact piece 6A and the second movable contact piece 6B. As a result, the first movable contact piece 6A and the second movable contact piece 6B return to their respective disconnected positions due to the elastic forces of the first movable contact piece 6A and the second movable contact piece 6B. As a result, the first transmission line 24A and the second transmission line 25A are disconnected from each other in the first RF line 21A. In addition, in the second RF line 21B, the third transmission line 24B and the fourth transmission line 25B are isolated from each other.

[0056] For example, when an RF signal is input to the first input terminal 26A and the second input terminal 26B of the electromagnetic relay 1, the electromagnetic relay 1 is closed. In this case, the first transmission line 24A and the second transmission line 25A are connected to each other, and the third transmission line 24B and the fourth transmission line 25B are connected to each other. Therefore, the RF signal passes from the first input terminal 26A through the first RF line 21A and is output from the first RF terminal 27A. The RF signal passes from the second input terminal 26B through the second RF line 21B and is output from the second RF terminal 27B. Meanwhile, the RF signal is cut by the first DC line 22A and the second DC line 22B, respectively, and is therefore prevented from being output from the first DC terminal 30A and the second DC terminal 30B.

[0057] When a DC signal is input to the first input terminal 26A and the second input terminal 26B of the electromagnetic relay 1, the electromagnetic relay 1 is in an open state. In this state, the first transmission line 24A and the second transmission line 25A are disconnected from each other, and the third transmission line 24B and the fourth transmission line 25B are disconnected from each other. Therefore, the DC signal is output from the first input terminal 26A through the first DC line 22A and the first DC terminal 30A without passing through the first RF line 21A. The DC signal is output from the second input terminal 26B through the second DC line 22B and the second DC terminal 30B without passing through the second RF line 21B. This prevents the DC signal from flowing through the first movable contact 6A and the second movable contact 6B.

[0058] In the above-described electromagnetic relay 1, the movable block 42 includes a first biasing member 56 that contacts the coil base 40 when the first movable contact piece 6A is in the open position and generates a biasing force on the iron piece 50 in a direction toward the first attraction portion 47. Therefore, in order to adjust the operating voltage, the spring load characteristics can be adjusted by adjusting the biasing force of the first biasing member 56. This makes it possible to prevent the impedance value from deviating from the design value compared to when the spring load characteristics are adjusted by bending the first movable contact piece 6A. As a result, it is possible to prevent deterioration of the high-frequency characteristics.

[0059] Furthermore, since the first biasing member 56 can be seen through the first opening 401 when the case 2 is removed, it is possible to adjust the biasing force of the first biasing member 56, for example, by inserting an adjustment jig through the first opening 401. The biasing force of the second biasing member 57 can also be adjusted by inserting an adjustment jig through the second opening 402.

[0060] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

[0061] The configuration of the transmission line base 3 is not limited to that of the above embodiment and may be modified. The configuration of the transmission lines of the transmission line base 3 is not limited to that of the above embodiment and may be modified. For example, the second RF line 21B and the second DC line 22B may be omitted. The configuration of the terminals of the transmission line base 3 is not limited to that of the above embodiment and may be modified. For example, the second input terminal 26B, the second RF terminal 27B, and the second DC terminal 30B may be omitted. A signal may flow in the opposite direction to that of the above embodiment. The configuration of the base assembly 4 is not limited to that of the above embodiment and may be modified. For example, the stand 5 is not limited to being separate from the coil base 40 and may be integrated with it.

[0062] The first DC line 22A of the transmission line base 3 may be configured to be connected to the second transmission line 25A. The second DC line 22B of the transmission line base 3 may be configured to be connected to the fourth transmission line 25B.

[0063] The first biasing member 56 may be a separate member from the first hinge spring 51. Similarly, the second biasing member 57 may be a separate member from the second hinge spring 52.

[0064] When the first movable contact piece 6A and the second movable contact piece 6B are in the open position, the first biasing member 56 may come into contact with the spool 44 of the coil block 41 to generate a biasing force on the iron piece 50 in a direction toward the first attraction portion 47. Similarly, when the first movable contact piece 6A and the second movable contact piece 6B are in the open position, the second biasing member 57 may come into contact with the spool 44 of the coil block 41 to generate a biasing force on the iron piece 50 in a direction toward the first attraction portion 47.

[0065] 3: Transmission line base, 6A: First movable contact piece, 25A: Second transmission line (an example of a fixed contact), 33A: First contact portion (an example of a movable contact), 40: Coil base (an example of a base), 41: Coil block, 42: Movable block, 43: Coil, 47: First attraction portion, 48: Second attraction portion, 50: Iron piece, 55: Movable insulating base, 56: First biasing member, 401: First opening, First end 501, 502: Second end, 561: First free end

Claims

1. An electromagnetic relay comprising: a fixed contact; a movable contact piece including a movable contact facing the fixed contact, the movable contact piece being movable between a closed position in which the movable contact is in contact with the fixed contact and an open position in which the movable contact is separated from the fixed contact; a base; a coil block including a coil and an iron core including a first attraction portion and disposed on the base; an armature that rotates as it is attracted to the first attraction portion of the iron core by the electromagnetic force of the coil; a card that moves the movable contact piece to the closed position in response to the rotation of the armature; and a movable block including a biasing member that contacts the base or the coil block when the movable contact piece is in the open position, for generating a biasing force on the armature in a direction toward the first attraction portion, the movable contact piece moving between the open position and the closed position.

2. The electromagnetic relay according to claim 1, wherein the biasing member is spaced apart from the base when the movable contact piece is in the closed position.

3. An electromagnetic relay as described in claim 1, further comprising a permanent magnet, the iron core further including a second attraction portion, and the armature including a first end attracted to the first attraction portion by the electromagnetic force of the coil, and a second end attracted to the second attraction portion by the magnetic force of the permanent magnet.

4. The electromagnetic relay according to claim 1, wherein said base includes an opening facing said biasing member, and said biasing member includes a free end visible through said opening.

5. An electromagnetic relay as set forth in claim 1, wherein the card is disposed above the movable contact piece, the armature is disposed above the card, and the biasing member is disposed above a lower end of the armature.

6. The electromagnetic relay according to claim 1, wherein said movable block further includes an insulating member that supports said armature and said biasing member.

7. An electromagnetic relay as described in claim 6, wherein the movable block further includes a hinge spring that functions as a rotation axis of the insulating member, the hinge spring being integral with the biasing member and protruding from the insulating member in a first direction, and the biasing member protruding from the insulating member in a second direction intersecting the first direction.

8. The electromagnetic relay according to claim 1, further comprising a transmission line base disposed below said movable contact piece, and said movable block disposed above said movable contact piece.

9. The electromagnetic relay according to claim 8, further comprising a shield plate disposed above said movable contact, said biasing member being disposed above said shield plate.

10. An electromagnetic relay as set forth in claim 8, wherein the biasing member does not overlap the movable contact piece when viewed from above.

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