JP6287128B2 - Backflow prevention device - Google Patents

Description

  The present invention relates to a backflow prevention device.

Conventionally, a device including a diode and a relay is known as a backflow prevention device (see, for example, Patent Document 1). The relay includes a coil and a contact connected in parallel to the coil. The contact is closed when a current flows through the coil. The diode is connected in series with the coil.
The coil and the diode are connected in parallel with the contact. When a current flows in the forward direction with respect to the diode, the coil is excited and the contact is closed. Thereby, energy loss in the diode is suppressed. Further, even if a current is about to flow in the reverse direction with respect to the diode, the contact is kept open, so that the backflow of the current is prevented.

JP-A-6-70484

  When the backflow prevention device as described above is used in, for example, a solar power generation system, an overcurrent may occur due to a ground fault or a short circuit between solar panels. In this case, the diode and the contact of the backflow prevention device may be damaged by the overcurrent. The subject of this invention is preventing the damage of the backflow prevention apparatus by overcurrent.

  A backflow prevention device according to one embodiment of the present invention includes an input terminal, an output terminal, a circuit connecting the input terminal and the output terminal, a diode, a coil, a contact mechanism portion, and a fuse. The diode is disposed between the input terminal and the output terminal in the circuit. The diode allows a current flow from the input terminal to the output terminal and regulates a current flow from the output terminal to the input terminal. The coil is arranged in series with the input terminal and the diode in the circuit. The contact mechanism is connected in parallel to the diode in the circuit. The contact mechanism unit maintains a shut-off state when the current flowing through the coil is less than a predetermined operation threshold, and enters a connected state when a current equal to or greater than the operation threshold flows through the coil. The fuse is connected in series with the diode in the circuit.

  In the backflow prevention device according to this aspect, the fuse constitutes a protection circuit against overcurrent. For this reason, when an overcurrent flows into a circuit, it can prevent that a diode or a contact mechanism part is damaged. In addition, when an overcurrent flows through the circuit, an open failure is caused in the backflow prevention device, so that a system equipped with the backflow prevention device can be protected.

  Preferably, the overcurrent prevention device further includes a terminal block. The terminal block supports the coil and the contact mechanism unit, and the input terminal and the output terminal are attached to the terminal block. The fuse is housed inside the terminal block. In this case, even if a large fuse with a large breaking current is mounted, an increase in the overcurrent prevention device can be suppressed.

  Preferably, the input terminal is disposed at one end of the terminal block, and the output terminal is disposed at the other end of the terminal block. The fuse is disposed between the input terminal and the output terminal. In this case, the fuse can be accommodated in the terminal block in a compact manner.

  Preferably, the fuse is arranged along the longitudinal direction of the terminal block. In this case, the fuse can be accommodated in the terminal block in a compact manner.

  Preferably, the backflow prevention device further includes a terminal block. The terminal block supports the coil and the contact mechanism unit, and the input terminal and the output terminal are attached to the terminal block. The fuse and the diode are accommodated inside the terminal block. The input terminal is disposed at the first corner of the terminal block. An output terminal is arrange | positioned at the 2nd corner | angular part located in the diagonal of the 1st corner | angular part of a terminal block. The fuse is disposed along the longitudinal direction of the terminal block. The fuse is disposed between the input terminal and the output terminal in the longitudinal direction of the terminal block, and between the input terminal and the output terminal in the short direction of the terminal block. The diode is disposed between the fuse and the output terminal in the longitudinal direction of the terminal block and between the fuse and the output terminal in the short direction of the terminal block. In this case, the fuse and the diode can be accommodated in the terminal block in a compact manner.

  Preferably, the backflow prevention device further includes a connection member that connects the fuse and the coil. The connecting member is disposed so as to cross the fuse. In this case, it is possible to improve the degree of freedom of the layout of components arranged inside the terminal block.

  Preferably, the fuse includes a pair of base portions and a glass tube portion disposed between the pair of base portions. The connecting member is disposed so as to intersect with one of the pair of base portions. In this case, the glass tube portion having a lower strength than the base portion can be protected from the connection member.

  Preferably, the connection member is disposed so as to intersect with the base part having the same polarity as the connection member of the pair of base parts. In this case, even if the connecting member comes into contact with the base portion, a short circuit can be prevented.

  Preferably, the connection member has a plate shape. In this case, the heat dissipation effect of the connection member can be improved.

  Preferably, the fuse has a fuse body and a lead wire protruding from the fuse body. The lead wire is soldered to the connection member. The connecting member has a slit into which the lead wire is fitted. In this case, even if the soldered portion is melted by heat generation, it is possible to prevent the fuse from being detached from the connection member.

  Preferably, the fuse is connected to the input terminal or the output terminal via the lead wire without passing through the substrate. In this case, the fuse is connected directly to the terminal without going through the board, regardless of the board design, such as the board thickness, copper foil thickness, or pattern width. Can be improved.

  Preferably, the terminal block has a rib disposed so as to face the connection member. In this case, the shaking of the connecting member can be suppressed by the rib in the terminal block. In particular, even if the connecting member is long, contact with other members in the terminal block can be suppressed by suppressing the shaking of the connecting member.

  Preferably, the terminal block has a rib arranged to face the fuse. In this case, the movement of the fuse in the terminal block can be suppressed by the rib. In particular, even when the fuse is connected to the circuit without passing through the substrate, the movement of the fuse can be restricted by the rib.

  ADVANTAGE OF THE INVENTION According to this invention, damage to the backflow prevention apparatus by overcurrent can be prevented.

It is a perspective view of a backflow prevention device according to an embodiment. It is a top view of a backflow prevention device. It is a disassembled perspective view of a backflow prevention device. It is a disassembled perspective view of a backflow prevention device. It is VV sectional drawing in FIG. It is VI-VI sectional drawing in FIG. It is a bottom view which shows the structure inside a terminal block. It is a perspective view which shows the structure inside a terminal block. It is a perspective view which shows the structure inside a terminal block. It is an enlarged view of an input terminal. It is a bottom view of a terminal block. It is a top view of a base. It is a schematic diagram which shows the structure of the solar energy power generation system by which the backflow prevention apparatus was employ | adopted. It is a timing chart which shows operation | movement of the backflow prevention apparatus in a solar energy power generation system. It is a schematic diagram which shows the circuit structure of the backflow prevention apparatus which concerns on other embodiment.

  Hereinafter, a backflow prevention device according to an embodiment will be described with reference to the drawings. FIG. 1 is a perspective view of the backflow prevention device 1. FIG. 2 is a top view of the backflow prevention device 1. 3 and 4 are exploded perspective views of the backflow prevention device 1. FIG. As shown in FIGS. 1 to 4, the backflow prevention device 1 includes a base 2, a terminal block 3, a contact mechanism portion 4, an electromagnet block 5, and a case 6.

  The base 2 has a plate shape and is attached to the terminal block 3. A first mounting convex portion 21 is provided at one end of the base 2, and a second mounting convex portion 22 is provided at the other end of the base 2. The first mounting convex portion 21 is provided with a through hole 211. A through hole 221 is provided in the second mounting convex portion 22. By passing a screw (not shown) through the through hole 211 of the first mounting convex portion 21 and the through hole 221 of the second mounting convex portion 22, the backflow prevention device 1 can be mounted at a desired position.

  As shown in FIG. 4, a pair of engagement grooves 201 and 202 are provided on the bottom surface of the base 2. The pair of engagement grooves 201 and 202 are disposed so as to face each other with a space therebetween. The slide rail holder 7 is attached to the base 2 by engaging the slide rail holder 7 with the engagement grooves 201, 202.

  The terminal block 3 supports the contact mechanism portion 4, the electromagnet block 5, and the case 6. The terminal block 3 has a substantially box-like shape with an open bottom. In plan view, the terminal block 3 has a substantially rectangular shape. The terminal block 3 is larger than the case 6 in the longitudinal direction of the terminal block 3. In the present embodiment, the “longitudinal direction” means the longitudinal direction of the terminal block 3 unless otherwise specified.

  Specifically, the terminal block 3 includes a first side portion 31, a second side portion 32, and a terminal block body 33. The 1st side part 31, the 2nd side part 32, and the terminal block main body 33 are located in a line with the longitudinal direction. The terminal block body 33 is located between the first side portion 31 and the second side portion 32. The case 6 is attached to the terminal block main body 33. The first side portion 31 protrudes from the case 6 in one of the longitudinal directions. The second side portion 32 protrudes from the case 6 to the other side in the longitudinal direction.

  The opening at the bottom of the terminal block 3 is closed by the base 2. As shown in FIG. 3, a first mounting portion 331 and a second mounting portion 332 for mounting the electromagnet block 5 to the terminal block 3 are provided on the upper surface of the terminal block body 33. The first attachment portion 331 and the second attachment portion 332 protrude from the upper surface of the terminal block body 33.

  The first side portion 31 is provided with a first input recess 311 and a second input recess 312. The first input recess 311 and the second input recess 312 have a shape recessed downward from the upper surface of the first side portion 31. A first connection screw 71 is disposed so as to penetrate the bottom surface of the first input recess 311, and the first connection screw 71 is screwed into the input terminal 11 described later. The second side portion 32 is provided with a first output recess 321 and a second output recess 322. The first output recess 321 and the second output recess 322 have a shape recessed downward from the upper surface of the second side portion 32. A second connection screw 72 is disposed so as to penetrate the bottom surface of the first output recess 321, and the second connection screw 72 is screwed to the output terminal 12 described later. Thereby, the output terminal 12 and the input terminal 11 are attached to the terminal block 3.

  A first relay terminal 13, a diode 8, and a fuse 9 are attached to the terminal block 3. The first relay terminal 13, the diode 8, and the fuse 9 are disposed inside the terminal block 3. The internal structure of the terminal block 3 will be described in detail later.

  The electromagnet block 5 is disposed on the terminal block 3. The electromagnet block 5 is fixed to the first mounting portion 331 and the second mounting portion 332 of the terminal block 3 by the first screw 73 and the second screw 74. In the present embodiment, the direction in which the electromagnet block 5 is disposed with respect to the terminal block 3 is referred to as “upward”, and the opposite direction is referred to as “downward”. The contact mechanism unit 4 is attached to the electromagnet block 5. The contact mechanism unit 4 is disposed above the electromagnet block 5.

  The case 6 has a substantially box-like shape with an open bottom. The case 6 is made of, for example, a resin having translucency. An electromagnet block 5 and a contact mechanism unit 4 are disposed inside the case 6. The case 6 is attached to the terminal block 3. Specifically, a locking hole 601 is provided in the vicinity of the opening edge of the case 6. A locking projection 301 is provided on the side surface of the terminal block 3. The case 6 is attached to the terminal block 3 by the locking protrusions 301 of the terminal block 3 being locked in the locking holes 601 of the case 6. Further, a first groove 302 and a second groove 303 extending in the short direction of the terminal block 3 are provided on the upper surface of the terminal block 3. When the case 6 is attached to the terminal block 3, the opening edge of the case 6 is disposed in the first groove 302 and the second groove 303. In the present embodiment, the short direction means the short direction of the terminal block 3 unless otherwise specified.

  5 is a cross-sectional view taken along the line VV in FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. As shown in FIG. 5, the electromagnet block 5 includes a coil 51, a spool 52, a core 53, and a yoke 54. The coil 51 is wound around the spool 52. The core 53 is inserted into the center hole of the spool 52. The core 53 is made of a magnetic material such as iron. One end of the core 53 is fixed to the yoke 54. A magnetic pole portion 531 is provided at the other end of the core 53. The magnetic pole portion 531 protrudes from one end portion of the spool 52. The outer diameter of the magnetic pole portion 531 is larger than the inner diameter of the center hole of the spool 52. The magnetic pole portion 531 has a flat end face.

  The yoke 54 is made of a magnetic material. The yoke 54 has a bent plate shape. Specifically, the yoke 54 has an upper surface portion 541, a side surface portion 542, and a bottom surface portion 543. The top surface portion 541 and the bottom surface portion 543 are connected by a side surface portion 542. The coil 51 described above is disposed between the upper surface portion 541 and the bottom surface portion 543. The core 53 is fixed to the side surface part 542.

  As shown in FIG. 6, the contact mechanism unit 4 includes a movable contact member 41 and a fixed contact member 42. The movable contact member 41 is supported so as to be swingable with respect to the yoke 54. The fixed contact member 42 is fixed to the yoke 54. The movable contact member 41 includes an armature 43, a movable contact piece 44, and a movable contact piece support portion 45. The armature 43 is made of a magnetic material. The armature 43 is disposed so as to face the magnetic pole portion 531 of the core 53. The movable contact piece 44 is disposed above the yoke 54. The movable contact piece 44 is made of a conductive material. The movable contact piece 44 has a plate shape. A movable contact 441 is provided at the tip of the movable contact piece 44.

  The movable contact piece support portion 45 supports the movable contact piece 44. The movable contact piece support 45 is made of resin and is integrated with the movable contact piece 44 by insert molding. The upper part of the armature 43 is fixed to the movable contact piece support part 45. A lower portion of the armature 43 is disposed so as to face the magnetic pole portion 531 of the core 53. The armature 43 is supported so as to be swingable with respect to the yoke 54. As shown in FIG. 5, a return spring 46 is attached to the movable contact piece support portion 45. The return spring 46 urges the armature 43 in a direction in which the armature 43 moves away from the magnetic pole portion 531.

  The fixed contact member 42 includes a fixed contact piece 47, a fixed contact piece support portion 48, and a support base 49. The fixed contact piece 47 is disposed above the movable contact piece 44. The fixed contact piece 47 is made of a conductive material. The fixed contact piece 47 has a plate shape. A fixed contact 471 is provided at the tip of the fixed contact piece 47. The fixed contact 471 is located above the movable contact 441.

  The fixed contact piece support portion 48 supports the fixed contact piece 47. The fixed contact piece support 48 is made of resin. The fixed contact piece 47 is attached to the bottom surface of the fixed contact piece support 48. The second relay terminal 14 is attached to the fixed contact piece support 48. The return spring 46 described above is pressed against the bottom surface of the fixed contact piece support portion 48 in a state where the armature 43 is in contact with the magnetic pole portion 531 of the core 53. The second relay terminal 14 is connected to the movable contact piece 44 by a lead wire (not shown). The second relay terminal 14 is attached to the upper surface of the fixed contact piece support 48.

  As shown in FIG. 1, in the backflow prevention device 1 according to the present embodiment, two fixed contact pieces 47 and two second relay terminals 14 are provided. Although not shown, two movable contact pieces 44 are also provided. That is, the backflow prevention device 1 according to the present embodiment has two sets of fixed contact pieces 47 and movable contact pieces 44.

  The support base 49 is disposed below the fixed contact piece support portion 48. The support base 49 is disposed below the movable contact piece 44. The support base 49 is disposed above the yoke 54. The support base 49 is attached to the upper surface of the yoke 54 via the insulating sheet 40. As shown in FIG. 5, the support base 49 is attached to the yoke 54 by a screw 75 together with the fixed contact piece support portion 48. A contact support portion 491 is attached to the upper surface of the support base 49. The contact support portion 491 is located below the movable contact 441. In a state where the armature 43 is separated from the magnetic pole portion 531, the movable contact 441 contacts the contact support portion 491.

  The operation of the contact mechanism unit 4 is as follows. When the current flowing through the coil 51 is less than the predetermined operation threshold, the armature 43 is in a state of being separated from the magnetic pole portion 531. At this time, the movable contact 441 and the fixed contact 471 are not in contact with each other and are electrically disconnected (blocked state). When a current exceeding the operation threshold value flows through the coil 51, the electromagnet block 5 is excited to attract the armature 43 to the magnetic pole portion 531 against the urging force of the return spring 46, and the armature 43 becomes the magnetic pole portion 531. To touch. At this time, the movable contact 441 and the fixed contact 471 come into contact with each other and are electrically connected (connected state). When the current flowing through the coil 51 falls below a predetermined return threshold value, the armature 43 is separated from the magnetic pole portion 531 by the biasing force of the return spring 46. Thereby, when the movable contact 441 leaves | separates from the fixed contact 471, the contact mechanism part 4 returns to a interruption | blocking state.

  Next, the internal configuration of the terminal block 3 will be described in detail. FIG. 7 is a bottom view showing an internal configuration of the terminal block 3. 8 and 9 are perspective views showing the internal configuration of the terminal block 3. FIG. Inside the terminal block 3, an input terminal 11, an output terminal 12, a first relay terminal 13, a fuse 9, a connecting member 10, and a diode 8 are arranged.

  The input terminal 11 is disposed at the first corner 313 of the terminal block 3. The output terminal 12 is disposed at the second corner 323 of the terminal block 3. The first corner 313 is provided on the first side portion 31. The second corner portion 323 is provided on the second side portion 32. The second corner 323 is located on the opposite side of the first corner 313. Therefore, the input terminal 11 and the output terminal 12 are arranged with a gap in the longitudinal direction and the short direction.

  The first relay terminal 13 is disposed adjacent to the output terminal 12. The first relay terminal 13 is aligned with the output terminal 12 in the short direction of the terminal block 3. The first relay terminal 13 is disposed at the center of the terminal block 3 in the short direction.

  The fuse 9 is disposed between the input terminal 11 and the output terminal 12. The fuse 9 is disposed along the longitudinal direction. The fuse 9 is disposed between the input terminal 11 and the output terminal 12 in the longitudinal direction and between the input terminal 11 and the output terminal 12 in the short direction of the terminal block 3. The fuse 9 is disposed at the center of the terminal block 3 in the longitudinal direction. The fuse 9 is disposed at the center of the terminal block 3 in the short direction of the terminal block 3. The fuse 9 is arranged side by side with the first relay terminal 13 in the longitudinal direction.

  The terminal block 3 has a first boss portion 34 and a second boss portion 35. A first screw 73 for fixing the above-described electromagnet block 5 to the terminal block 3 is disposed on the first boss portion 34. A second screw 74 for fixing the above-described electromagnet block 5 to the terminal block 3 is disposed on the second boss portion 35. The 1st boss | hub part 34 and the 2nd boss | hub part 35 are arrange | positioned at intervals in a longitudinal direction. The first boss part 34 and the second boss part 35 are arranged with a gap in the short direction of the terminal block 3.

  The fuse 9 is disposed between the first boss portion 34 and the second boss portion 35. The fuse 9 is longer than the distance between the first boss part 34 and the second boss part 35 in the longitudinal direction. In the longitudinal direction, the fuse 9 is longer than the diode 8.

  The fuse 9 includes a fuse body 91, a first lead wire 92, and a second lead wire 93. The fuse body 91 has a substantially cylindrical shape. The fuse body 91 includes a first base part 94, a second base part 95, and a glass tube part 96. The first base portion 94 is disposed at a position closer to the input terminal 11 than the output terminal 12 in the longitudinal direction. The second base portion 95 is disposed at a position closer to the output terminal 12 than the input terminal 11 in the longitudinal direction. The glass tube portion 96 is disposed between the first base portion 94 and the second base portion 95.

  The first lead wire 92 and the second lead wire 93 protrude from the fuse body 91. The first lead wire 92 protrudes from the first base 94 in a direction perpendicular to the axis of the fuse body 91. The second lead wire 93 projects from the second base portion 95 in a direction perpendicular to the axis of the fuse body 91. The first lead wire 92 and the second lead wire 93 protrude from the fuse body 91 in the same direction. Specifically, the first lead wire 92 and the second lead wire 93 protrude from the fuse body 91 toward the input terminal 11 in the short direction of the terminal block 3.

  The first lead wire 92 is connected to the input terminal 11. FIG. 10 is an enlarged view of the input terminal 11. The input terminal 11 includes a terminal main body 111 and a connection portion 112. The terminal body 111 has a plate shape. The terminal body 111 is provided with a screw hole 113 into which the first connection screw 71 described above is screwed. The connection part 112 protrudes from the terminal body 111. The connection part 112 has a first connection hole 114, a second connection hole 115, and a third connection hole 116. The first connection hole 114 and the second connection hole 115 are connected by a slit 117. The slit 117 extends in the longitudinal direction of the connection portion 112 from the tip of the connection portion 112. The first connection hole 114 is located between the tip of the connection part 112 and the second connection hole 115. The third connection hole 116 is located between the slit 117 and the terminal body 111.

  As shown in FIG. 7, the first lead wire 92 is inserted into the first connection hole 114. The first lead wire 92 is fitted into the first connection hole 114 by being press-fitted into the slit 117. The first lead wire 92 is soldered to the connection portion 112 of the input terminal 11. As a result, the first lead wire 92 is connected to the input terminal 11. Thus, the fuse 9 is connected to the input terminal 11 without going through the substrate.

  Note that the output terminal 12 and the first relay terminal 13 have the same shape as the input terminal 11. For this reason, in the drawing, the same reference numerals are given to the configurations of the output terminal 12 and the first relay terminal 13 corresponding to the configuration of the output terminal 12.

  The connection member 10 connects the fuse 9 and the coil 51. The connecting member 10 has an elongated plate shape. The connection member 10 has a first connection end 101 and a second connection end 102. The first connection end 101 is provided with a slit 103. The second lead wire 93 of the fuse 9 described above is fitted into the slit 103 of the first connection end 101 by being press-fitted into the slit 103 of the first connection end 101. The second lead wire 93 is soldered to the first connection end 101. As a result, the second lead wire 93 is connected to the first connection end 101. Thus, the fuse 9 is connected to the connection member 10 without going through the substrate.

  The second connection end 102 is provided with a slit 104. FIG. 11 is a bottom view of the terminal block 3. As shown in FIG. 11, the terminal block 3 is provided with a through hole 333 through which the first lead wire 511 (see FIG. 6) of the coil 51 is passed. As shown in FIG. 7, the first lead wire 511 of the coil 51 is fitted into the slit 104 of the second connection end 102 by being press-fitted into the slit 104 of the second connection end 102. The first lead wire 511 is soldered to the second connection end portion 102. Thereby, the first lead wire 511 is connected to the second connection end portion 102.

  The first connection end portion 101 and the second connection end portion 102 are disposed on opposite sides with the fuse 9 interposed therebetween. Therefore, the connection member 10 is disposed so as to intersect the fuse 9 in the bottom view. Specifically, the first connection end portion 101 is located in the direction in which the first lead wire 92 and the second lead wire 93 protrude from the fuse body 91. The second connection end portion 102 is located in a direction opposite to the direction in which the first lead wire 92 and the second lead wire 93 protrude from the fuse body 91.

  The first connection end portion 101 is disposed at a position closer to the output terminal 12 than the input terminal 11 in the longitudinal direction. The first connection end portion 101 is arranged at a position closer to the input terminal 11 than the output terminal 12 in the short direction of the terminal block 3. The second connection end 102 is disposed at a position closer to the input terminal 11 than the output terminal 12 in the longitudinal direction. The second connection end 102 is disposed at a position closer to the output terminal 12 than the input terminal 11 in the short direction of the terminal block 3.

  The connecting member 10 is disposed so as to intersect with the second base part 95 in the bottom view. The second lead wire 93 protruding from the second base portion 95 is connected to the connection member 10 at the first connection end portion 101. Therefore, the connection member 10 is disposed so as to intersect with the second base portion 95 having the same polarity as the connection member 10 in the bottom view. Further, the connection member 10 is disposed so as to pass between the first boss portion 34 and the second boss portion 35 in a bottom view. As shown in FIG. 9, the connection member 10 has a shape bent in the vertical direction so as to get over the fuse 9.

  As shown in FIG. 11, the terminal block 3 is provided with a through hole 334 through which the second lead wire 512 of the coil 51 is passed. The second lead wire 512 of the coil 51 is inserted into the second connection hole 115 of the first relay terminal 13. The second lead wire 512 is soldered to the first relay terminal 13. As a result, the second lead wire 512 is connected to the first relay terminal 13.

  A relay lead wire 131 is connected to the first relay terminal 13. As shown in FIG. 11, the terminal block 3 is provided with a through hole 335 through which the relay lead 131 is passed. The relay lead 131 is inserted into the third connection hole 116 of the first relay terminal 13. The relay lead 131 is soldered to the first relay terminal 13. As a result, the second lead wire 512 is connected to the first relay terminal 13. The relay lead 131 is connected to the second relay terminal 14 described above.

  As shown in FIG. 1, the output lead wire 121 is connected to the fixed contact piece 47 described above. As shown in FIG. 11, the terminal block 3 is provided with a through hole 336 through which the output lead 121 is passed. The output lead 121 is inserted into the second connection hole 115 of the output terminal 12. The output lead wire 121 is soldered to the output terminal 12. As a result, the output lead 121 is connected to the output terminal 12.

  A diode 8 is connected to the first relay terminal 13 and the output terminal 12. The diode 8 includes a diode body 81, a first diode lead wire 82, and a second diode lead wire 83. The first diode lead wire 82 protrudes from the diode body 81 in one axial direction of the diode body 81. The second diode lead wire 83 projects from the diode body 81 to the other axial direction of the diode body 81.

  The first diode lead 82 is fitted into the first connection hole 114 of the first relay terminal 13 by being press-fitted into the slit 117 of the first relay terminal 13. The first diode lead wire 82 is soldered to the first relay terminal 13. Accordingly, the first diode lead wire 82 is connected to the first connection hole 114 of the first relay terminal 13. The second diode lead 83 is fitted into the first connection hole 114 of the output terminal 12 by being press-fitted into the slit 117 of the output terminal 12. The second diode lead 83 is soldered to the output terminal 12. Accordingly, the second diode lead wire 83 is connected to the first connection hole 114 of the output terminal 12.

  The diode 8 is disposed between the fuse 9 and the output terminal 12 in the longitudinal direction and between the fuse 9 and the output terminal 12 in the short direction. The diode 8 is disposed between the first relay terminal 13 and the output terminal 12 in the short direction. The diode 8 is disposed between the second boss portion 35 and the output terminal 12 in the longitudinal direction. As shown in FIG. 11, the terminal block 3 is provided with diode support ribs 309 that support the diode 8.

  As shown in FIG. 11, the terminal block 3 includes a first lateral support rib 304, a second lateral support rib 305, and a third lateral support rib 306. The first lateral support rib 304, the second lateral support rib 305, and the third lateral support rib 306 are disposed so as to face the fuse 9. The first lateral support rib 304, the second lateral support rib 305, and the third lateral support rib 306 support the fuse 9 from the side of the fuse 9.

  The first lateral support rib 304 and the second lateral support rib 305 are disposed so as to face each other. The fuse 9 is disposed between the first lateral support rib 304 and the second lateral support rib 305. Specifically, the first base portion 94 is disposed between the first lateral support rib 304 and the second lateral support rib 305.

  The third lateral support rib 306 is disposed so as to face the second boss portion 35. The fuse 9 is disposed between the third lateral support rib 306 and the second boss portion 35. Specifically, the second base portion 95 is disposed between the third lateral support rib 306 and the second boss portion 35.

  The terminal block 3 includes a first upper support rib 307 and a second upper support rib 308. The first upper support rib 307 is located on one side of the fuse 9. The second upper support rib 308 is located on the other side of the fuse 9. The first upper support rib 307 and the second upper support rib 308 are disposed so as to face the connection member 10. The first upper support rib 307 and the second upper support rib 308 support the connection member 10 above the connection member 10.

  FIG. 12 is a top view of the base 2. In FIG. 12, the positions of the fuse 9 and the connecting member 10 are indicated by a two-dot chain line. As shown in FIG. 12, the base 2 has a first lower fuse support rib 203 and a second lower fuse support rib 204. The first lower fuse support rib 203 is located below the first base portion 94. The first lower fuse support rib 203 is disposed so as to face the first base portion 94. The first lower fuse support rib 203 supports the first base portion 94. The second lower fuse support rib 204 is located below the second base part 95. The second lower fuse support rib 204 is disposed so as to face the second base portion 95. The second lower fuse support rib 204 supports the second base part 95.

  The base 2 has a first lower support rib 205 and a second lower support rib 206. The first lower support rib 205 is located below the first upper support rib 307. The second lower support rib 206 is located below the second upper support rib 308. The first lower support rib 205 and the second lower support rib 206 support the connection member 10 below the connection member 10.

  The base 2 has a first boss cover part 207 and a second boss cover part 208. The first boss cover part 207 is located below the first boss part 34. The first boss cover part 207 covers the first boss part 34 from below. The second boss cover portion 208 is located below the second boss portion 35. The second boss cover portion 208 covers the second boss portion 35 from below.

  The fuse 9 is disposed between the first boss cover portion 207 and the second boss cover portion 208. Further, the connecting member 10 is disposed so as to pass between the first boss cover part 207 and the second boss cover part 208.

  FIG. 13 is a schematic diagram illustrating a configuration of a solar power generation system 100 in which the backflow prevention device 1 according to the present embodiment is employed. The solar power generation system 100 includes a solar cell 200, a storage battery 300, and a backflow prevention device 1. The solar cell 200 is connected to the input terminal 11 of the backflow prevention device 1. The storage battery 300 is connected to the output terminal 12 of the backflow prevention device 1. Moreover, the circuit 15 which connects the input terminal 11 and the output terminal 12 is comprised by the structure of the backflow prevention apparatus 1 mentioned above, as shown in FIG.

  In this circuit 15, a diode 8 is disposed between the input terminal 11 and the output terminal 12. The diode 8 allows a current flow from the input terminal 11 to the output terminal 12 and restricts a current flow from the output terminal 12 to the input terminal 11. A coil 51 is arranged in series with the input terminal 11 and the diode 8. The contact mechanism unit 4 is connected to the diode 8 in parallel. The fuse 9 is disposed between the input terminal 11 and the coil 51 and is connected to the diode 8 in series. In FIG. 13, the coil 51 is disposed between the input terminal 11 and the diode 8, but the coil 51 may be disposed between the diode 8 and the output terminal 12.

  FIG. 14 is a timing chart showing the operation of the backflow prevention device 1 in the solar power generation system 100. FIG. 14A shows a change in the value of the current flowing through the backflow prevention device 1. FIG. 14B shows a change in the state of the contact mechanism unit 4 in the backflow prevention device 1.

  In the solar power generation system 100, when the solar cell 200 generates power, a current flows to the coil 51 through the input terminal 11. When sunlight is weak and the value of the current flowing through the coil 51 is less than a predetermined operation threshold I_th1 (eg, 3A) (from time t0 to time t1), the electromagnet block 5 is not excited. For this reason, the contact mechanism part 4 is maintained by the interruption | blocking state (OFF). Therefore, the current supplied from the solar battery 200 is charged to the storage battery 300 via the diode 8. In addition, when the amount of power generated by the solar battery 200 is small and the voltage of the storage battery 300 is higher than the voltage of the solar battery 200, the current tries to flow backward from the storage battery 300 to the solar battery 200. Therefore, the diode 8 prevents the current from flowing backward. Thereby, it is possible to prevent a reverse current from flowing into the solar cell 200 and to prevent the solar cell 200 from being damaged.

  On the other hand, when sunlight is strong and the current value flowing through the coil 51 becomes equal to or higher than the operation threshold value I_th1 (time point t1), the electromagnet block 5 is excited, and the contact mechanism unit 4 changes from the cut-off state (OFF) to the connected state (ON). Switch. Therefore, the current supplied from the solar battery 200 bypasses the diode 8 and charges the storage battery 300 via the contact mechanism unit 4 having a small electrical resistance value. For this reason, when the power generation amount in the solar cell 200 is large, a large current does not flow through the diode 8. Therefore, it is possible to suppress the occurrence of problems such as energy loss in the diode 8 or damage to the diode 8.

  Note that when the value of the current flowing through the coil 51 is equal to or greater than the predetermined return threshold I_th2 (from time t1 to time t2), the contact mechanism unit 4 is maintained in the connected state (ON). When the current value becomes less than the return threshold I_th2 (time point t2), the contact mechanism unit 4 is switched from the connection state (ON) to the cutoff state (OFF).

  As described above, in the backflow prevention device 1 according to the present embodiment, when an overcurrent flows in the circuit 15 due to a ground fault or a short circuit between panels of the solar battery 200, the fuse 9 is blown, so that the circuit 15 is protected. That is, the fuse 9 forms a protection circuit against overcurrent. For this reason, it is possible to prevent the diode 8 or the contact mechanism 4 from being damaged when an overcurrent flows through the circuit 15. Further, when the overcurrent flows through the circuit 15, the system 100 in which the backflow prevention device 1 is mounted can be protected by causing the backflow prevention device 1 to fail open.

  The fuse 9 is accommodated in the terminal block 3 and arranged along the longitudinal direction. The fuse 9 is disposed between the input terminal 11 and the output terminal 12 in the longitudinal direction and between the input terminal 11 and the output terminal 12 in the short direction of the terminal block 3. For this reason, the fuse 9 can be accommodated in the terminal block 3 in a compact manner. Further, the diode 8 is disposed between the fuse 9 and the output terminal 12 in the longitudinal direction and between the fuse 9 and the output terminal 12 in the short direction of the terminal block 3. For this reason, the fuse 9 and the diode 8 can be accommodated in the terminal block 3 in a compact manner.

  A connecting member 10 that connects the fuse 9 and the coil 51 is disposed so as to intersect the fuse 9. Therefore, the fuse 9 can be arranged in the terminal block 3 regardless of the protruding direction of the lead wires 92 and 93 from the fuse 9 or the positional relationship between the input terminal 11 and the output terminal 12. Thereby, the freedom degree of the layout of the components arrange | positioned inside the terminal block 3 can be improved.

  The connecting member 10 is disposed so as to intersect the second base part 95. For this reason, the glass tube part 96 having low strength can be protected from the connection member 10. Further, since the second base part 95 has the same polarity as the connection member 10, even if the connection member 10 comes into contact with the second base part 95, a short circuit can be prevented.

  The connecting member 10 has a plate shape. For this reason, the heat dissipation effect of the connection member 10 can be improved.

  The second lead wire 93 is fitted in the slit 103 of the connecting member 10. For this reason, even if the soldering portion that fixes the second lead wire 93 and the connection member 10 is melted by heat generation, the fuse 9 is prevented from being detached from the connection member 10.

  The fuse 9 is connected to the input terminal 11 via the first lead wire 92 without passing through the substrate. Further, the fuse 9 is connected to the coil 51 via the connection member 10 without passing through the substrate. For this reason, compared with the case where the fuse 9 is mounted on the substrate, the heat radiation effect can be improved regardless of the substrate design, such as the substrate thickness, the copper foil thickness, or the pattern width. .

  The terminal block 3 includes a first lateral support rib 304, a second lateral support rib 305, and a third lateral support rib 306 that support the fuse 9. The base 2 has a first lower fuse support rib 203 and a second lower fuse support rib 204. For this reason, the movement of the fuse 9 in the terminal block 3 can be suppressed by these ribs. Therefore, even if the fuse 9 is connected to the circuit 15 without a substrate as in the present embodiment, the movement of the fuse 9 can be restricted by these ribs. In particular, the movement of the fuse 9 in the lateral direction can be restricted by the first lateral support rib 304, the second lateral support rib 305, and the third lateral support rib 306. Further, the movement of the fuse 9 in the vertical direction can be restricted by the first lower fuse support rib 203 and the second lower fuse support rib 204.

  The terminal block 3 includes a first upper support rib 307 and a second upper support rib 308 that support the connection member 10. The base 2 includes a first lower support rib 205 and a second lower support rib 206. For this reason, it is possible to prevent the connecting member 10 from shaking up and down in the terminal block 3 by these ribs. In particular, as in the present embodiment, the connection member 10 is arranged so as to intersect the fuse 9, so that even if the length of the connection member 10 increases, the terminal block is suppressed by suppressing the shaking of the connection member 10. Contact with other members in 3 can be suppressed.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of invention.

  The input terminal 11, the relay terminal, the output terminal 12, the diode 8, and the fuse 9 are not limited to the positions and shapes of the above-described embodiments, and may be changed. For example, as shown in FIG. 15, the fuse 9 may be disposed between the diode 8 and the output terminal 12 in the circuit 15.

  The connecting member 10 is not limited to the position and shape of the above-described embodiment, and may be changed. For example, the connection member 10 may be disposed so as not to intersect the fuse 9. The connecting member 10 is not limited to a plate shape, and may be a linear shape.

  The contact mechanism unit 4 and the electromagnet block 5 are not limited to the configuration of the embodiment described above, and may be changed. For example, in the above embodiment, the number of sets of the movable contact 441 and the fixed contact 471 is two, but may be one or three or more.

  The terminal block 3 is not limited to the shape of the above embodiment, and may be changed. For example, the terminal block 3 may be substantially square when viewed from the bottom. Alternatively, the terminal block 3 may have a shape other than a square when viewed from the bottom. The ribs of the terminal block 3 may be omitted. Similarly, the rib of the base 2 may be omitted.

  ADVANTAGE OF THE INVENTION According to this invention, the damage of the backflow prevention apparatus by overcurrent can be prevented.

DESCRIPTION OF SYMBOLS 11 Input terminal 12 Output terminal 15 Circuit 8 Diode 51 Coil 4 Contact mechanism part 9 Fuse 1 Backflow prevention device 3 Terminal block 10 Connection member 94 1st cap part 95 2nd cap part 96 Glass tube part 91 Fuse main body 92 1st lead wire 93 Second lead wire 304 First lateral support rib 305 Second lateral support rib 306 Third lateral support rib 307 First upper support rib 308 Second upper support rib

Claims (10)

  An input terminal;
  An output terminal;
  A circuit for connecting the input terminal and the output terminal;
  A diode disposed between the input terminal and the output terminal in the circuit, allowing a current flow from the input terminal to the output terminal, and restricting a current flow from the output terminal to the input terminal; ,
  A coil disposed in series with the input terminal and the diode in the circuit;
  A contact mechanism that is connected in parallel to the diode in the circuit, maintains a shut-off state when a current flowing through the coil is less than a predetermined operating threshold value, and enters a connected state when a current greater than the operating threshold value flows through the coil. And
  A fuse connected in series with the diode in the circuit;
  A terminal block that supports the coil and the contact mechanism, and to which the input terminal and the output terminal are attached;
  A connecting member for connecting the fuse and the coil;
With
  The fuse is housed inside the terminal block;
  The fuse has a pair of base parts, and a glass tube part disposed between the pair of base parts,
  The connecting member is disposed so as to intersect with one of the pair of base parts.
Backflow prevention device. The input terminal is disposed at one end of the terminal block,
The output terminal is disposed at the other end of the terminal block;
The fuse is disposed between the input terminal and the output terminal;
The backflow prevention device according to claim 1. The fuse is disposed along a longitudinal direction of the terminal block;
The backflow prevention device according to claim 1 or 2. The fuse and the diode are housed inside the terminal block,
The input terminal is disposed at a first corner of the terminal block;
The output terminal is disposed at a second corner portion located diagonally to the first corner portion of the terminal block,
The fuse is disposed along the longitudinal direction of the terminal block,
The fuse is disposed between the input terminal and the output terminal in the longitudinal direction of the terminal block, and between the input terminal and the output terminal in the short direction of the terminal block,
The diode is disposed between the fuse and the output terminal in the longitudinal direction of the terminal block, and between the fuse and the output terminal in the short direction of the terminal block.
The backflow prevention device according to claim 1. The connection member is arranged so as to intersect the base part having the same polarity as the connection member among the pair of base parts.
The backflow prevention device according to any one of claims 1 to 4 . The connecting member has a plate shape,
The backflow prevention device according to any one of claims 1 to 5 . The fuse has a fuse body and a lead wire protruding from the fuse body,
The lead wire is soldered to the connection member,
The connection member has a slit into which the lead wire is fitted.
The backflow prevention device according to any one of claims 1 to 6 . The fuse is connected to the input terminal or the output terminal via the lead wire without going through a substrate.
The backflow prevention device according to claim 7 . The terminal block has a rib disposed so as to face the connection member.
The backflow prevention device according to any one of claims 1 to 8 . The terminal block has a rib arranged to face the fuse.
The backflow prevention device according to any one of claims 1 to 9 .

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