JP5428709B2 - Fuse holder - Google Patents

Description

  The present invention relates to a fuse holder.

  Conventionally, as a fuse holder mounted on a circuit board, one described in Patent Document 1 below is known. The fuse holder of Patent Document 1 is fixed to a circuit board by soldering and is electrically connected so that the fuse can be inserted and removed. Thereby, when the fuse is blown, the replacement work of the fuse can be easily performed.

JP 2005-100940 A

  In the above configuration, when the fuse is inserted or removed, a force in the insertion / extraction direction acts between the fuse holder and the circuit board due to friction between the fuse and the fuse holder. As a result, stress concentrates on the electrical connection portion (solder portion) between the fuse holder and the circuit board. For this reason, a solder part may be damaged and there exists a possibility that the electrical connection of a fuse holder and a circuit board may be disconnected. The present invention has been completed based on the above-described circumstances, and an object thereof is to provide a fuse holder that can further improve the reliability of electrical connection with a circuit board.

The present invention is a fuse holder that is mounted on a circuit board and in which a fuse is detachable, and is formed integrally with the fuse terminal connection portion, the fuse terminal connection portion into which the terminal portion of the fuse can be inserted and removed, and the circuit A holding leg that is fixed to a board and holds the fuse terminal connection part, a board connection leg that is conductively fixed to a conductive part formed on the surface of the circuit board, the fuse terminal connection part, and the board A stress relieving portion provided between the connecting leg portion and elastically deformable when the fuse is attached and detached, and the holding leg portion is formed at an end portion of the fuse terminal connecting portion on the circuit board side. The stress relaxation portion extends from the end of the fuse terminal connection portion opposite to the circuit board toward the circuit board, and the board connection leg portion is a front end of the stress relaxation portion. In particular with the features provided on the end portion of the circuit board side.

  When the terminal portion of the fuse is inserted into and removed from the fuse terminal connecting portion, the terminal portion comes into contact with the fuse terminal connecting portion, so that stress in the insertion / extraction direction acts between the fuse holder and the circuit board. In the present invention, an elastically deformable stress relaxation portion is provided between the board connection leg portion and the fuse terminal connection portion. With such a configuration, when the fuse is inserted and removed, the stress relaxing portion is elastically deformed, so that the stress acting on the board connecting leg portion is relaxed. As a result, it is possible to prevent the fixing portion between the board connection leg part and the conductive part of the circuit board from being damaged, and to increase the electrical connection reliability. By the way, if it is only for making electrical connection reliability high, what is necessary is just the structure provided only with the board | substrate connection leg part, without providing a holding | maintenance leg part. However, if the fuse terminal connection part and the circuit board are fixed only via the board connection leg part, the stress relaxation part will be elastically deformed when the fuse is inserted and removed, so that the fuse terminal connection part is difficult to hold and work. Sex is reduced. Therefore, in the present invention, a holding leg portion is provided in addition to the board connecting leg portion, and the fuse terminal connecting portion is held on the circuit board via the holding leg portion. In this way, the fuse terminal connection portion can be securely held when the fuse is inserted and removed, and the workability is improved.

  Further, the stress relaxation portion may have a bellows shape. If it is a bellows shape, compared with the shape which can be elastically deformed by a coil spring, for example, formation of a stress relaxation part will become easy. In particular, when the stress relaxation portion is formed from a plate material, it is only necessary to bend the plate material into a bellows shape, which is preferable.

  The fuse terminal connecting portion and a frame capable of accommodating the fuse may be provided, and the frame may be provided with a fuse support portion capable of coming into contact with the accommodated fuse from below. With such a configuration, it is possible to protect the connection portion between the terminal portion of the fuse and the fuse terminal connection portion by accommodating the fuse terminal connection portion and the fuse in the frame. Further, the accommodated fuse can be received by the fuse support. For this reason, the force at the time of fuse attachment can be received by the frame, and the stress acting on the board connecting leg can be further reduced.

  In addition, the fuse terminal connecting portion includes a pair of opposed flat plates, and both the flat plates are formed with contact portions that can contact the terminal portion of the fuse by protruding toward the fuse side. Can be.

  Further, the fuse terminal connecting portion has a substantially box shape having a terminal insertion hole through which the terminal portion is inserted, and a portion of the wall portion constituting the terminal insertion hole that faces the terminal portion is inward. By projecting, a pair of contact portions capable of sandwiching the terminal portion is formed, and the holding leg portion extends from the lower end of the fuse terminal connecting portion along the planar direction of the circuit board, and the stress relaxation The part extends from the upper end of the fuse terminal connection part to the circuit board side, and the board connection leg part extends from the lower end of the stress relaxation part along the planar direction of the circuit board. Can be.

  ADVANTAGE OF THE INVENTION According to this invention, the fuse holder which can make electrical connection reliability with a circuit board higher can be provided.

1 is an exploded perspective view showing a schematic configuration of a fuse holder according to Embodiment 1 of the present invention. Perspective view showing fuse holder Front sectional view showing the internal structure of the fuse holder Front sectional view showing fuse installation work Front view showing fuse holder Side view showing fuse holder Top view showing fuse holder Top view showing the frame Front view showing terminal contact piece Side view showing terminal contact piece The disassembled perspective view which shows schematic structure of the fuse holder which concerns on Embodiment 2 of this invention. Perspective view showing fuse holder Front view showing fuse holder Side view showing fuse holder Front sectional view showing the internal structure of the fuse holder Side sectional view showing the internal structure of the fuse holder Top view showing fuse holder Front sectional view showing fuse installation work Cross-sectional side view showing fuse installation work Front view showing terminal contact piece Plan view showing terminal contact piece Front sectional view showing terminal contact piece

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, a fuse holder 30 according to the present embodiment is configured such that a fuse 20 having a substantially rectangular parallelepiped shape is detachably attached to a circuit board 10, and a frame 40 having a box shape and the frame And a pair of terminal contact pieces 60 attached to 40. The fuse 20 includes a fusing part (not shown) sealed inside, and terminal parts 21 electrically connected to the fusing part and attached to both ends in the longitudinal direction of the fuse 20.

  Both terminal contact pieces 60 are in electrical contact with the terminal portion 21 of the fuse 20. Both terminal contact pieces 60 have the same shape, and are attached to both ends in the longitudinal direction of the frame 40 with one terminal contact piece 60 facing the other terminal contact piece 60. In the following description, the direction from the fuse holder 30 toward the circuit board 10 (lower side in FIG. 3) is the lower side, and the opposite direction (upper side in FIG. 3) is the upper side. Moreover, let the left-right direction in FIG. 3 be a length direction (longitudinal direction of the frame 40). Also, the vertical direction in FIG. 7 is the width direction, and in this width direction, the upper side in FIG. 7 is the rear side, and the lower side is the front side.

  Next, the configuration of the frame 40 will be described. The frame 40 accommodates the terminal contact piece 60 and the fuse 20, and is formed by transfer molding or injection molding of an insulating material such as epoxy resin or plastic. As shown in FIG. 1, the frame 40 has a substantially box shape with an upper opening, and can accommodate the terminal contact piece 60 and the fuse 20 from above. Further, as shown in FIG. 3, a substantially conical fuse support portion 41A having a flat upper surface protrudes from the center portion in the length direction and the width direction of the bottom wall 41 of the frame 40. . The fuse 20 accommodated in the frame 40 is configured to be supported on the upper surface of the fuse support portion 41A.

  As shown in FIGS. 1 and 8, in the bottom wall 41, contact piece accommodating portions 41 </ b> B are formed by vertically penetrating both end sides in the length direction (the direction in which the fuse 20 is attached and detached). Each contact piece accommodating portion 41 </ b> B can accommodate each main body portion 61 (described later) of each terminal contact piece 60. Further, side wall openings 42B that open downward by penetrating the lower side of both side walls 42 in the length direction are respectively formed, and each side wall opening 42B is communicated with each contact piece accommodating part 41B. . Also, as shown in FIGS. 4 and 5, the upper opening 45 is formed by opening upward the portion corresponding to the central portion in the longitudinal direction of the fuse 20 in the front wall 43 and the rear wall 44 of the frame 40. Has been. As shown in FIG. 5, the longitudinal center portion of the fuse 20 is exposed from the front side (and the rear side), and is inserted into the fuse holder 30 by inserting a finger through the upper opening portions 45. The fuse 20 can be gripped.

  As shown in FIG. 5, at both ends and the central portion of the front wall 43 and the rear wall 44 in the length direction, leg portions 46 are formed so as to protrude toward the circuit board 10 side. The leg 46 is close to (or may be in contact with) the circuit board 10. Thus, when the frame 40 is pressed from above, the frame 40 is supported on the circuit board 10 via the leg portions 46.

  Next, the configuration of the terminal contact piece 60 will be described. The terminal contact piece 60 is formed, for example, by punching and bending a thin metal plate, and has electrical conductivity. As shown in FIG. 1 and FIG. 9, the terminal contact piece 60 includes a main body portion 61 that is vertically long and flat, a pressing piece 71 and a pressing piece 65 that extend from the upper end of the main body portion 61, and the main body portion 61. The stress relaxation part 66 formed by folding downward from the upper end of the main part is mainly constituted. Since the left and right terminal contact pieces 60 have the same configuration, the right terminal contact piece 60 will be basically described in the following description.

  As shown in FIG. 3 and FIG. 9, in the main body 61, the contact portion 62 is formed by projecting a portion facing the terminal portion 21 of the fuse 20 in a curved shape inward (terminal portion 21 side). . As shown in FIG. 4, the facing interval A <b> 1 between the projecting ends of both contact portions 62 is set to be slightly smaller than the total length A <b> 2 of the fuse 20. Moreover, both the contact parts 62 can be elastically deformed outside (the side away from the terminal part 21). With the above configuration, the fuse 20 can be clamped from both sides in the longitudinal direction by the both contact portions 62. In other words, a pair of main body portions 61 (a pair of flat plates) arranged to face each other so as to sandwich the terminal portion 21 constitute a fuse terminal connection portion into which the terminal portion 21 of the fuse 20 can be inserted and removed.

  As shown in FIG. 3, the terminal portion 21 of the fuse 20 is configured to contact the protruding end of the contact portion 62. In this way, for example, the contact portion 62 has a flat shape, and the contact area between the contact portion 62 and the fuse 20 can be reduced as compared with a configuration in which the contact portion 62 and the fuse 20 come into contact with each other. Thereby, the frictional force between the fuse 20 and the contact part 62 at the time of insertion / extraction of the fuse is reduced, and the force required for insertion / extraction of the fuse 20 can be reduced.

  As shown in FIGS. 4 and 9, a holding leg 63 is formed integrally with the main body 61 by bending the lower end of the main body 61 at a right angle to the inside. Further, a locking claw 64 is formed by bending a part of the main body portion 61 so as to rise and incline outward (to the left and right sides in FIG. 4). The locking claw 64 can be elastically deformed in the length direction with the base end side as a fulcrum. As shown in FIG. 4, the locking claw 64 is configured to be locked to the lower surface 42 </ b> A of the side wall 42 of the frame (in other words, the upper side of the side wall opening 42 </ b> B), and the terminal contact piece 60 moves upward. The terminal contact piece 60 has a function of preventing the terminal contact piece 60 from coming off.

  As shown in FIGS. 3 and 9, the pressing piece 71 extends so as to be inclined upward toward the inner side (side toward the fuse 20). A tip 71 </ b> A of the pressing piece 71 is disposed above the fuse 20. Thereby, the end of the fuse 20 can be pressed from above by the lower surface of the pressing piece 71. The pressing piece 65 is extended from the tip (upper end) of the pressing piece 71 so as to be inclined upward, and the upper surface of the pressing piece 65 is a pressing surface 65A that is inclined upward. That is, the pressing piece 71 and the pressing piece 65 constitute a substantially V-shaped plate piece that is recessed inward. As shown in FIG. 4, the main body 61 is disposed to face the side wall 42 of the frame 40 with a slight gap. Thereby, by pressing the pressing surface 65A of the pressing piece 65 from above, it is possible to deform the main body portion 61 in the direction of opening outward by the amount of the gap, and to increase the facing distance between the contact portions 62. It has become.

  The stress relaxation part 66 includes a connecting part 67 that inclines downward and an extendable part 68 that extends downward from the lower end of the connecting part 67. The expansion / contraction part 68 is bent in a bellows shape, and is elastically deformable so as to expand and contract in the vertical direction of FIG. 3 (the direction in which the fuse 20 is attached to and detached from the fuse holder 30). Thereby, the expansion-contraction part 68 can be elastically deformed with insertion / extraction of the fuse 20.

  The board connection leg 69 is extended by bending the lower end of the expansion / contraction part 68 outward at a right angle. That is, the stress relaxation part 66 is provided between the main body part 61 (fuse terminal connection part) and the board connection leg part 69. The length of the stress relaxation part 66 is set so that the height of the board connection leg part 69 is arranged at the same height as the holding leg part 63. As shown in FIGS. 6 and 10, the pressing piece 65 and the stress relaxation part 66 are arranged adjacent to each other in the width direction. For this reason, when attached to the frame 40, as shown in a plan view of FIG. 7, the stress relaxation portion 66 in the other terminal contact piece 60 is arranged opposite to the pressing piece 65 in the one terminal contact piece 60. Is done.

  Next, assembly and mounting of the fuse holder 30 will be described. First, the both terminal contact pieces 60 are attached to the frame 40. Specifically, as shown in FIG. 1, the main body portions 61 are inserted into the contact piece accommodating portions 41 </ b> B from above, with the stress relaxation portions 66 of the terminal contact pieces 60 facing outward. At this time, the locking claw 64 of the main body 61 contacts the inner surface of the side wall 42 and deforms inward. Furthermore, when each main body portion 61 is inserted into each contact piece housing portion 41 </ b> B, the tip of the locking claw 64 reaches the lower side of the side wall 42. Then, as shown in FIG. 3, the locking claw 64 is elastically restored and locked to the lower surface 42 </ b> A of the side wall 42. Thereby, the attachment of the both terminal contact pieces 60 to the frame 40 is completed, and the assembly of the fuse holder 30 is completed.

  Next, the fuse holder 30 is disposed at a predetermined position of the circuit board 10, and the holding leg 63 and the board connection leg 69 are soldered to the lands 12 and 13 formed on the circuit board 10 in a surface mounted state, respectively. (A solder part is shown with the code | symbol 11 and refer FIG.4 and FIG.5.). Here, the land 12 to which the board connecting leg 69 is soldered is electrically connected to the wiring pattern 14 formed on the circuit board 10. In other words, the board connection leg 69 is fixed to the wiring pattern 14 (conductive part) formed on the surface of the circuit board 10 so as to be conductive, and the board connection leg 69 is electrically connected to the land 12. . On the other hand, the holding leg 63 is fixed to the land 13 of the circuit board 10 by soldering (solder part 11), whereby the terminal contact piece 60 is held on the circuit board 10. The land 13 to which the holding leg 63 is soldered is not electrically connected to the wiring pattern formed on the circuit board 10. That is, the electrical connection between the terminal contact piece 60 and the wiring pattern 14 of the circuit board 10 is performed only through the board connection leg 69.

  Next, an operation when the fuse 20 is attached to the fuse holder 30 mounted on the circuit board 10 will be described. First, the operator grasps the vicinity of the center in the longitudinal direction of the fuse 20 and inserts the fuse 20 from the opening above the frame 40. In this insertion process, as shown in FIG. 4, the pressing surfaces 65 </ b> A of both pressing pieces 65 are pressed from above at both ends of the fuse 20 (only the left pressing piece 65 is shown in FIG. 4). Then, both the pressing pieces 65 and both pressing pieces 71 are bent and deformed so as to open outward. As described above, the main body 61 is disposed with a slight gap between the main body 61 and the side wall 42 of the frame 40. For this reason, with the deformation of both pressing pieces 65, the facing distance between both contact portions 62 in both terminal contact pieces 60 is slightly larger than the length A1 in the natural state. As a result, the insertion force required to insert the fuse 20 between the contact portions 62 is reduced. When the pressing surface 65A is further pressed after the main body 61 comes into contact with the side wall 42, the pressing piece 71 is deformed outward with the base end as a fulcrum. Thus, by opening the pressing piece 71 outward, the tip 71A of the pressing piece 71 is displaced to a position where it is retracted from above the fuse 20 (shown by a two-dot chain line in FIG. 3). As a result, the fuse 20 can be inserted between the contact portions 62 from above.

  The fuse 20 is inserted between the contact portions 62 while pressing the curved surfaces on the upper side of the contact portions 62 with the terminal portion 21 of the fuse 20 so as to spread both the contact portions 62 outward. Eventually, the lower surface of the fuse 20 comes into contact with the fuse support portion 41A. Accordingly, the fuse 20 is supported by the fuse support portion 41 </ b> A and is held by being pressed by the both contact portions 62. And each contact part 62 contacts each terminal part 21, respectively, and the electrical connection of the fuse holder 30 and the fuse 20 is made.

  When the fuse 20 is inserted to the position shown in FIG. 3, the pressing of the pressing piece 65 by the fuse 20 is released, and the pressing piece 71 is elastically returned to the initial state (the state of FIG. 3). Accordingly, the terminal portions 21 of the fuse 20 are pressed from above by the lower surfaces of the pressing pieces 71, and the fuse 20 is prevented from being detached. With the above operation, the attachment of the fuse 20 is completed. Instead of pressing the pressing piece 65 with the fuse 20, the pressing piece 65 may be pressed by hand.

  In the mounting process described above, both terminal contact pieces 60 are pressed toward the circuit board 10 by the frictional force generated when the terminal portions 21 of the fuse 20 slide on the contact portions 62. For this reason, the stress in the direction in which the circuit board 10 is pressed acts on the holding leg 63 and the board connecting leg 69 which are the fixing points between the terminal contact piece 60 and the circuit board 10. Here, the board connection leg 69 is connected to the main body 61 via a stress relaxation part 66 that can be expanded and contracted in the fuse attaching / detaching direction. For this reason, when the fuse 20 is attached, the stress relaxing portion 66 contracts, so that the stress acting on the board connecting leg 69 is relaxed, and the stress acting on the solder portion 11 is relaxed. On the other hand, the holding leg 63 receives most of the force when the fuse 20 is inserted. As described above, by providing the stress relaxation portion 66, it is possible to prevent the stress caused by the insertion of the fuse from being concentrated on the holding leg portion 63 side and concentrated on the board connection leg portion 69 side. For this reason, it is possible to prevent damage to the solder portion 11, which is a connection portion between the board connection leg 69 and the circuit board 10, and to further increase electrical reliability.

  Next, an operation for removing the fuse 20 from the fuse holder 30 will be described. For example, when an overcurrent flows in a circuit pattern on the circuit board 10 and the fuse 20 is blown for circuit protection, it is necessary to remove the fuse 20 in order to replace it with another fuse. In such a case, first, the operator presses the pressing surfaces 65A of the pressing pieces 65 from above, and displaces the tip 71A of the pressing piece 71 to a position where it is retracted from above the fuse 20 when the fuse 20 is mounted. Thereby, it is possible to avoid the interference between the fuse 20 and the pressing piece 71 and to take out the fuse 20 from between the contact portions 62. Subsequently, with both pressing pieces 65 being pressed, a finger is inserted from the upper opening 45 of the frame 40, the vicinity of the center of the fuse 20 in the longitudinal direction is gripped, and the fuse 20 is removed.

  In this removal process, force is applied in a direction (upward direction in FIG. 5) in which both terminal contact pieces 60 are separated from the circuit board 10 due to frictional force generated when the terminal portions 21 of the fuse 20 slide on the contact portions 62. Works. When the pressing surface 65A is pressed from above, the terminal contact piece 60 is pressed against the circuit board 10 side. For this reason, if the fuse 20 is removed in a state where both the pressing pieces 65 are pressed as described above, the connection location between the terminal contact pieces 60 and the circuit board 10 (the holding leg 63 and the board connecting leg 69). ) Acting in the pulling direction (direction away from the circuit board 10) can be reduced.

  Furthermore, the stress relaxing portion 66 expands (elastically deforms) with the removal of the fuse, so that the stress acting on the board connecting leg 69 side and thus the solder portion 11 is relaxed. For this reason, even when the fuse 20 is removed, the stress acting on the connection portion (solder part 11) between the board connection leg 69 and the circuit board 10 can be relieved, and the breakage of the solder part 11 can be prevented. As a result, the electrical connection reliability between the fuse holder 30 and the circuit board 10 can be increased.

  As described above, in the present embodiment, the stress relaxation portion 66 that can be elastically deformed is provided between the board connection leg portion 69 and the main body portion 61. With such a configuration, when the fuse 20 is inserted and removed, the stress relaxing portion 66 is elastically deformed, so that the stress acting on the board connecting leg 69 is relaxed. As a result, it is possible to prevent the fixing portion between the board connection leg portion 69 and the solder portion 11 of the circuit board 10 from being damaged, and to improve the electrical connection reliability. By the way, if it is only for making electrical connection reliability high, what is necessary is just the structure provided only with the board | substrate connection leg part 69, without the holding leg part 63 being provided. However, if the main body 61, the circuit board 10, and the board connecting leg 69 are fixed only, the stress relieving part 66 is deformed when the fuse 20 is inserted and removed, so that the main body 61 is not held and workability is improved. Decreases. Therefore, in the present embodiment, a holding leg 63 is provided in addition to the board connecting leg 69, and the main body 61 is held on the circuit board 10 via the holding leg 63. In this way, the main body 61 can be reliably held when the fuse 20 is inserted and removed, and workability is improved.

  Further, the stress relaxation portion 66 has a bellows shape. If it is a bellows shape, compared with the shape which can be elastically deformed by a coil spring, for example, formation of the stress relaxation part 66 will become easy. In particular, when the stress relieving portion 66 is formed from a plate material as in the present embodiment, it is only necessary to bend the plate material into a bellows shape.

  Further, the frame 40 is provided with the terminal contact piece 60 and the fuse 20, and the frame 40 is formed with a fuse support portion 41 </ b> A capable of coming into contact with the stored fuse 20 from below. With such a configuration, the contact portion between the terminal portion 21 of the fuse 20 and the terminal contact piece 60 can be protected by housing the terminal contact piece 60 and the fuse 20 in the frame 40. Further, the accommodated fuse 20 can be received by the fuse support 41A. For this reason, the force at the time of attaching the fuse can be received also by the frame 40, and the force acting on the board connecting leg 69 can be further reduced.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the type of fuse is different from that of the first embodiment, and the configuration of the fuse holder is also different correspondingly. In the following description, the horizontal direction in FIG. 13 is the length direction, and the vertical direction in FIG. 17 is the width direction. Further, the upper side in FIG. 17 is the rear side, and the lower side is the front side. In the second embodiment, the same reference numerals are used for the portions having the same names as those in the first embodiment, and the description of the structure, operation, and effect is omitted.

  As shown in FIG. 11, the fuse 120 inserted into and removed from the fuse holder 130 of the present embodiment connects a pair of flat-plate-shaped terminal portions 121 with a fusing portion (not shown), and includes a terminal portion 121 including the fusing portion. This is a blade-type fuse in which the base end side is housed in an insulating housing 122. The distal end side of each terminal portion 121 protrudes downward from the insulating housing 122 and is inserted into and removed from the fuse holder 130. In the following description, the direction from the fuse holder 130 toward the circuit board 10 (the lower side in FIG. 13) is the lower side, and the opposite direction (the upper side in FIG. 13) is the upper side.

  As shown in FIG. 11, the fuse holder 130 according to the present embodiment includes a pair of terminal contact pieces 160 into which the terminal portions 121 are respectively inserted and extracted, and a frame 140 to which the both terminal contact pieces 160 are attached. Both terminal contact pieces 160 have the same shape, and are accommodated in the frame 140 in a state where one terminal contact piece 160 is rotated 180 degrees with respect to the other.

  First, the configuration of the frame 140 will be described. The frame 140 has a function of accommodating and holding the terminal contact piece 160 and the fuse 120, and is formed by transfer molding or injection molding of an insulating material such as epoxy resin or plastic. The frame 140 has a substantially box shape in which the inside is vertically penetrated, and the fuse 120 can be fitted from above. As shown in FIG. 15, a partition wall 141 is formed on the lower side in the frame 140 so as to connect the front wall 143 and the rear wall 144 of the frame 140. By this partition wall 141, the lower side in the internal space of the frame 140 is partitioned at the center in the width direction, and serves as a contact piece accommodating portion 141 </ b> B that can accommodate each terminal contact piece 160.

  The upper end of the partition wall 141 of the frame 140 is a fuse support portion 141A. In the state where the fuse 120 is housed in the frame 140, the lower surface of the insulating housing 122 in the fuse 120 abuts on the upper surface of the fuse support portion 141A, so that the fuse 120 can be supported. A side wall opening 142B is formed by penetrating the lower side of both side walls 142 of the frame 140 in the length direction (see FIG. 14). The side wall opening 142B communicates with the contact piece accommodating portion 141B, and a stress relaxation portion 166 of a terminal contact piece 160 described later protrudes outside the frame 140 through the side wall opening 142B (see FIGS. 12 and 12). 14).

  As shown in FIG. 13, upper openings 145 are formed in the front wall 143 and the rear wall 144 of the frame 140 by opening portions corresponding to the central portion in the length direction of the fuse 120 upward. . As shown in FIG. 13, the central portion in the length direction of the fuse 120 (insulating housing 122) is exposed from the front side (and the rear side), and the fuse 120 is inserted by inserting a finger through the upper opening portions 145. The (insulating housing 122) can be gripped.

  As shown in FIG. 13, on the front wall 143 and the rear wall 144, leg portions 146 are formed at both ends and the central portion in the length direction so as to protrude toward the circuit board 10. The leg portions 146 are in contact with (or close to) the circuit board 10. Thus, when the frame 140 is pressed from above, the frame 140 is supported on the circuit board 10 via the leg portions 146.

  Next, the configuration of the terminal contact piece 160 will be described. The terminal contact piece 160 is formed, for example, by punching and bending a thin metal plate, and has electrical conductivity. As shown in FIGS. 11, 20, and 21, the terminal contact piece 160 includes a main body portion 161 (fuse terminal connection portion) having a terminal insertion hole 161 </ b> E through which the terminal portion 121 of the fuse 120 can be inserted, and a main body portion 161. The extended stress relaxation part 166 is mainly used. Since the left and right terminal contact pieces 160 have the same configuration, the right terminal contact piece 160 will be basically described in the following description.

  As shown in FIG. 21, the main body portion 161 is formed in a substantially box shape by bending a single metal thin plate at a right angle. As a result, a space (terminal insertion hole 161 </ b> E) in which the four sides are surrounded by the wall portion in a plan view is formed inside the main body portion 161. In other words, the terminal insertion hole 161E penetrates in the vertical direction (the direction in which the fuse 120 is attached / detached) and has a rectangular shape in plan view. In addition, the right side wall of the main body 161 is formed in an overlapping manner (the outer side wall is denoted by reference numeral 161A1 and the inner side wall is denoted by reference numeral 161A2). The rear wall of the main body 161 is also formed so as to overlap two (reference numeral 161B1 on the outer rear wall and reference numeral 161B2 on the inner rear wall). The main body 161 is set to have a length in the width direction shorter than a length in the length direction.

  As shown in FIG. 22, in the front wall 161 </ b> D and the rear wall 161 </ b> B <b> 2 (the wall portion constituting the terminal insertion hole 161 </ b> E, a pair of opposed plates) facing the terminal portion 121 of the fuse 120, as shown in FIG. 22. A pair of contact portions 162 (clamping portions) are formed so as to face each other. As shown in FIG. 19, the facing interval B <b> 1 at the protruding ends of both contact portions 162 is set to be slightly smaller than the length B <b> 2 of the terminal portion 121 in the width direction. Moreover, both the contact parts 162 can be elastically deformed outward. With the above configuration, both contact portions 162 are configured to be able to clamp the terminal portion 121 of the fuse 120 from both sides in the width direction. As shown in FIG. 17, both contact portions 162 are arranged so as to face from above the frame 140 through the contact piece accommodating portion 141 </ b> B. Accordingly, the terminal portion 121 can be inserted between the contact portions 162 by inserting the terminal portion 121 from above the frame 140.

  As shown in FIGS. 11 and 19, a holding leg 163 is integrally formed on the front wall 161 </ b> D of the main body 161 by bending the lower end thereof at a right angle to the front. In other words, the holding leg 163 extends along the planar direction of the circuit board 10. Further, a locking claw 164 that is bent substantially at a right angle is extended from the upper end of the front wall 161D of the main body 161 to the outside (front side) of the terminal contact piece 160. As shown in FIG. 19, the locking claw 164 is configured to be locked to the upper surface of the step portion 147 formed on the inner surface of the front wall 143 (or the rear wall 144) of the frame 140. By restricting the downward movement of the terminal contact piece 160, the frame 140 is prevented from being detached from the terminal contact piece 160 upward.

  The stress relaxation portion 166 extends from the upper end of the outer side wall 161A1 so as to be folded downward (circuit board side), and further extends downward from the connecting portion 167 inclined downward and the lower end of the connecting portion 167. A telescopic portion 168 extending to the right. The expansion / contraction part 168 is bent so as to form an accordion shape, and can be elastically deformed in such a manner as to expand and contract in the vertical direction of FIG. 13 (the direction in which the fuse 120 is attached to and detached from the fuse holder 130). The stress relaxation portion 166 is set to a length at which the lower end reaches the same height as the holding leg portion 163. A board connection leg 169 is formed on the stress relaxation part 166 by bending the lower end of the stress relaxation part 166 outward at a right angle. In other words, the board connection leg 169 extends along the planar direction of the circuit board 10. As shown in FIG. 11, the board connecting leg 169 and the holding leg 163 are extended in a shape orthogonal to each other in a plan view (a surface viewed from the attaching / detaching direction of the fuse 120).

  As described above, the two terminal contact pieces 160 are respectively accommodated in the frame 140 in a state of being rotated 180 degrees with respect to the other. For this reason, in the left terminal contact piece 160, the front, rear, left and right are opposite to the configuration of the right terminal contact piece 160. Specifically, as shown in FIG. 17, in the terminal contact piece 160 on the left side, the holding leg 163 protrudes to the rear side. Further, in the terminal contact piece 160 on the left side, the locking claw 164 is locked to a step portion 147 formed on the rear wall 144.

  Next, assembly and mounting of the fuse holder 130 will be described. First, the both terminal contact pieces 160 are attached to the frame 140. Specifically, as shown in FIG. 11, the terminal contact pieces 160 are aligned so that the stress relaxation portions 166 of the terminal contact pieces 160 face outward, and the contact pieces are accommodated from below. Each main body part 161 is inserted into the part 141B. At this time, the locking claws 164 of the main body 161 abut against the inner surface of the side wall 142 and elastically deform inward. Furthermore, when each main body 161 is inserted into each contact piece housing 141B, the tip of each locking claw 164 reaches the upper side of each step 147. Then, the locking claw 164 is elastically restored and locked to the upper surface of the step portion 147 (FIG. 16). Moreover, in this state, each stress relaxation part 166 is distribute | arranged so that it may protrude outside from each side wall opening 142B. Thereby, the attachment of the both terminal contact pieces 160 to the frame 140 is completed, and the assembly of the fuse holder 130 is completed.

  Next, the fuse holder 130 is disposed at a predetermined position of the circuit board 10, and the holding leg 163 and the board connection leg 169 are soldered to the lands 12 and 13 formed on the circuit board 10 in a surface-mounted state, respectively ( A solder part is shown by the code | symbol 11 and refer FIG.13 and FIG.15). Here, the land 12 to which the board connecting leg 169 is soldered is electrically connected to the wiring pattern 14 formed on the circuit board 10. In other words, the board connection leg 169 is fixed to the wiring pattern 14 (conductive part) formed on the surface of the circuit board 10 so as to be conductive. On the other hand, the holding leg part 163 is fixed to the circuit board 10 via the solder part 11, whereby the terminal contact piece 160 is held on the circuit board 10. The land 13 to which the holding leg 163 is soldered is not electrically connected to the wiring pattern formed on the circuit board 10. That is, the electrical connection between the terminal contact piece 160 and the wiring pattern 14 of the circuit board 10 is performed only via the board connection leg 169.

  Next, an operation when the fuse 120 is attached to the fuse holder 130 mounted on the circuit board 10 will be described. First, the operator grasps the vicinity of the upper portion of the insulating housing 122 of the fuse 120 and aligns each terminal portion 121 of the fuse 120 with each terminal contact piece 160, and then opens the fuse 120 from the opening above the frame 140. Insert it (Figs. 18 and 19). Soon, the tip of each terminal portion 121 is inserted into the body portion 161 (terminal insertion hole 161E) of each terminal contact piece 160 and comes into contact with the upper curved surface of both contact portions 162. Furthermore, when the fuse 120 is inserted, each terminal portion 121 is inserted between the contact portions 162 while pushing the contact portions 162 outward. Soon, the lower surface of the insulating housing 122 comes into contact with the fuse support 141A. As a result, the fuse 120 is supported by the fuse support portion 141 </ b> A and each terminal portion 121 is sandwiched between the contact portions 162. Thereby, the fuse holder 130 and the fuse 120 are electrically connected. With the above operation, the attachment of the fuse 120 is completed.

  In the mounting process described above, the terminal contact pieces 160 are pressed toward the circuit board 10 by the frictional force generated when the terminal parts 121 of the fuse 120 slide on the contact parts 62 of the terminal contact pieces 160, respectively. The For this reason, stress in the direction in which the circuit board 10 is pressed acts on the holding leg 163 and the board connecting leg 169, which are fixing points between the terminal contact piece 160 and the circuit board 10. Also in the present embodiment, the substrate connection leg portion 169 is connected to the main body portion 161 via the stress relaxation portion 166, as in the first embodiment. For this reason, when the fuse 120 is attached, the stress relaxing portion 166 contracts, so that the stress acting on the connection portion (solder portion 11) between the board connecting leg 169 and the circuit board 10 is relaxed. The holding leg 163 receives most of the force when the fuse 120 is inserted. As a result, it is possible to prevent stress generated with the insertion of the fuse from concentrating on the board connection leg 169 which is an electrical connection location. For this reason, the connection part (solder part 11) between the board connection leg 169 and the circuit board 10 is not broken, and electrical reliability can be ensured.

  Next, an operation when the fuse 120 is removed from the fuse holder 130 will be described. In order to remove the fuse 120, the operator inserts a finger from the upper opening 145 of the frame 140, grasps the upper portion of the insulating housing 122 in the fuse 120, and pulls out the fuse 120 upward.

  Each terminal portion 121 of the fuse 120 is sandwiched between both contact portions 162. For this reason, in the detaching process, a force acts in a direction in which both terminal contact pieces 160 are pulled away from the circuit board 10 due to friction when the terminal portion 121 and the contact portion 162 slide. In this case, the stress acting on the board connecting leg 169 becomes smaller than the stress acting on the holding leg 163 due to the stress relaxation part 166 extending slightly. Therefore, even when the fuse 120 is removed, the stress acting on the connection portion (solder portion 11) between the board connection leg 169 and the circuit board 10 (land 12 and wiring pattern 14) can be alleviated, and the solder portion 11 is broken. Can be prevented. As a result, the electrical reliability between the fuse holder 130 and the circuit board 10 can be increased.

  Moreover, in this embodiment, it was set as the structure which distribute | arranges the both-terminal contact piece 160 of the same shape in the form rotated mutually 180 degree | times. For this reason, as shown in FIG. 17, both holding leg parts 163 are arranged so as to extend in the front-rear direction. With such a configuration, the front and rear inclination of the fuse holder 130 that may occur when the fuse 120 is attached and detached can be regulated by the two holding legs 163.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  (1) In each of the above embodiments, the expansion / contraction portions 68 and 168 of the stress relaxation portions 66 and 166 have a bellows shape so that they can be expanded and contracted in the fuse attaching / detaching direction. However, the present invention is not limited to this. For example, it is good also as a structure which can be expanded-contracted in a fuse attachment / detachment direction by forming the stress relaxation parts 66 and 166 in the shape of a coil spring.

  (2) In each of the above embodiments, the terminal contact piece 60 and the circuit board 10 (wiring pattern 14) are electrically connected via the board connection legs 69 and 169, and the holding legs 63 and 163 are configured. The circuit board is not electrically connected to the wiring pattern of the circuit board. The holding legs 63 and 163 may be electrically connected to the wiring pattern 14 of the circuit board 10. In short, the electrical connection between the terminal contact piece 60 and the circuit board 10 (wiring pattern 14) only needs to be made through at least the board connection leg 69.

  (3) In each of the above embodiments, the configuration in which the fuse holders 30 and 130 are surface-mounted on the circuit board 10 is illustrated, but the present invention is not limited to this. A configuration may be employed in which a through hole is formed in the circuit board 10 and mounting is performed through the through hole. In the case of mounting through a through hole, for example, the holding leg portions 63 and 163 and the board connection leg portions 69 and 169 may have a pin shape that can be inserted into the through hole instead of a flat plate shape.

  (4) In the above-described embodiment, the configuration in which the pressing piece 65 and the pressing piece 71 are formed in each of the pair of terminal contact pieces 60 (main body portion 61) is not limited to this. The pressing piece 65 and the pressing piece 71 may be formed only on either one of the main body portions 61.

  (5) In the above-described embodiment, the contact portion 62 is curved. However, the shape of the contact portion 62 is not limited to this. For example, it is good also as V shape which protrudes the contact part 62 inside.

10 ... Circuit board 14 ... Wiring pattern (conductive part)
20, 120 ... fuse 21, 121 ... terminal portion 30, 130 ... fuse holder 40, 140 ... frame 41A, 141A ... fuse support portion 61, 161 ... main body (fuse terminal connection portion, flat plate)
62 ... contact portions 63, 163 ... holding leg portions 66, 166 ... stress relieving portions 69, 169 ... substrate connection leg portions 161B2 ... rear wall (wall portion constituting the terminal insertion hole, flat plate)
161D: Front wall (wall portion and flat plate constituting terminal insertion hole)
161E ... Terminal insertion hole 162 ... Contact part (clamping part)

Claims (5)

A fuse holder mounted on a circuit board and having a removable fuse,
A fuse terminal connecting portion capable of inserting and removing the terminal portion of the fuse;
A holding leg that is formed integrally with the fuse terminal connection, and is fixed to the circuit board to hold the fuse terminal connection;
A board connection leg fixed to be conductively conductive to a conductive part formed on the surface of the circuit board;
A stress relieving part provided between the fuse terminal connection part and the board connection leg part and elastically deformable with the attachment and detachment of the fuse ;
The holding leg is formed at the end on the circuit board side in the fuse terminal connecting portion,
The stress relieving part extends from the end of the fuse terminal connecting part opposite to the circuit board toward the circuit board,
The fuse holder, wherein the board connection leg is provided at an end of the stress relaxation part on the circuit board side .   The fuse holder according to claim 1, wherein the stress relaxation portion has a bellows shape. A frame capable of accommodating the fuse terminal connecting portion and the fuse;
3. The fuse holder according to claim 1, wherein a fuse support portion capable of supporting the fuse accommodated in the frame is formed in the frame. 4. The fuse terminal connecting portion includes a pair of flat plates arranged to face each other with the terminal portion interposed therebetween.
Each of the said flat plates is formed with the contact part which can contact the said terminal part by protruding to the said terminal part side, The Claim 1 characterized by the above-mentioned. Fuse holder. The fuse terminal connection portion has a substantially box shape having a terminal insertion hole through which the terminal portion is inserted,
In the wall portion constituting the terminal insertion hole, a pinching portion capable of pinching the terminal portion is formed by projecting inward a portion facing the terminal portion,
The holding leg is extended from the lower end of the fuse terminal connecting portion along the planar direction of the circuit board,
The stress relaxation part is extended from the upper end of the fuse terminal connection part to the circuit board side,
4. The fuse according to claim 1, wherein the board connection leg portion extends from a lower end of the stress relaxation portion along a planar direction of the circuit board. 5. holder.

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