JP2013034379A - Engagement structure of terminal for screw tightening - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent imperfect engagement between a terminal and an engagement part of a connection box body and engage the terminal with the engagement part securely and smoothly.SOLUTION: A peripheral wall 18 for housing a terminal and a pair of flexible engagement parts 19 located in the peripheral wall are provided at a connection box body 2 made of an insulation resin. A flame like part 34 for inserting a bolt head of a terminal 7 with an electric wire is engaged with the pair of engagement parts in the peripheral wall and the terminal is connected with a circuit, the other side of the connection, by tightening a screw. In the structure, a pair of ribs 32 is provided in the peripheral wall so as to be located adjacent to the pair of engagement parts, and a pair of ribs 35 is provided at both sides of the frame like part. In the engagement state of the terminal, inner surfaces of the ribs on the peripheral wall side are respectively placed in contact with outer surfaces of the ribs on the frame like part side. A curved surface 35c allows an outer surface of the frame like part 34 to continue into the outer surface of each rib 35 on the frame like part side.

Description

  The present invention relates to a screw fastening terminal locking structure in which a terminal with an electric wire for power supply or the like is locked in an electrical connection box, and in that state, the terminal is screwed and connected to a circuit such as a bus bar.

FIG. 6 shows one form of a conventional locking structure for a screw fastening terminal (see Patent Document 1).

  In this structure, a bus bar (not shown) is arranged on a terminal block 62 of a junction box main body (fuse block main body) 61 made of insulating resin, and a horizontal plate portion of a screw fastening terminal 63 with an electric wire on the bus bar. 68, and with the vertical frame-like portion 64 temporarily fixed by the pair of left and right engaging claws 65 of the connection box body 61, the bolt 66 is inserted through the slot hole of the terminal 63 and the hole portion of the bus bar. The terminal 63 is connected to the bus bar by being screwed into an inner nut (not shown).

  The frame-like portion 64 of the terminal 63 is raised vertically, the opening 67 in the frame-like portion follows the slot hole of the horizontal plate portion 68 of the terminal 63, and the wire crimping portion is formed on the base side bent vertically of the plate portion 68. 69 is formed. The head portion of the temporarily tightened bolt 66 passes through the opening 67 and the bolt shaft portion is slidably engaged with the slot hole. In this state, the bolt 66 is finally tightened. The locking claws 65 are provided on the vertical wall portion of the junction box main body 61 so as to protrude horizontally on the left and right sides, enter the opening 67 of the frame-shaped portion 64 and engage with the left and right ends of the frame-shaped portion 64. The upper end of the frame-like portion 64 is abutted and stopped by a rib 70 on the wall side.

  The electric wire 71 following the crimping part 69 of the terminal 63 is connected to an alternator or the like of the automobile. The bus bar is connected to a fusible link (not shown) in the junction box body 61, and the fusible link is connected to the load side by another electric wire 72 with a terminal. The junction box body 61 is mounted together with a relay, a fuse and a connector in an outer junction box body (frame) made of synthetic resin (not shown), and a cover (not shown) is attached to the outer junction box body (not shown). To constitute an electrical junction box.

JP 2006-4733 A (FIG. 1)

  However, in the conventional locking structure of the screw fastening terminal, when the terminal 63 is slidably engaged with the temporarily tightened bolt 66, the terminal 63 is not sufficiently pushed in (the locking claw 65). Is incompletely fitted to the frame-like portion 64), the contact area between the terminal 63 and the bus bar is reduced, causing trouble in electrical conduction, or the terminal 63 is rotated when the bolt 66 is tightened. There was a concern that positional displacement or interference would occur, or that the terminal 63 after tightening would be easily detached from the bolt 66 due to vibration or the like.

  Further, when the frame portion 64 is engaged with the locking claw (locking portion) 65 while sliding the terminal 63 along the bolt 66, the frame-shaped portion 64 abuts against the locking claw 65 and the engagement is smooth. There is a concern that it may cause the locking to be disengaged when the frame-shaped portion 64 is not carried out at the same time, or when the frame-like portion 64 is inserted into the locking claw 65 from an oblique direction, or when it is twisted.

  In view of the above, the present invention can prevent incomplete engagement between the terminal and the locking portion of the connection box body, and can securely lock (temporarily fix) the terminal to the locking portion. An object of the present invention is to provide a screw fastening terminal locking structure capable of smoothly and firmly engaging a terminal with a locking portion with good workability.

  In order to achieve the above-described object, a screw fastening terminal locking structure according to claim 1 of the present invention comprises a connection box body made of insulating resin, a terminal storage peripheral wall, and a pair of flexible terminals in the peripheral wall. A structure in which a locking portion is provided, a frame-like portion for inserting a bolt head of a terminal with an electric wire is locked in the peripheral wall by the pair of locking portions, and the terminal is screwed and connected to a mating circuit And a pair of ribs are provided on the peripheral wall adjacent to the pair of locking portions, and a pair of ribs are provided on both sides of the frame-shaped portion. The inner surface of the rib is in contact with the outer surface of the rib on the frame-like portion side.

  With the above configuration, in a state where the terminal is completely inserted into the peripheral wall and completely locked to the locking portion, the inner surface of the rib on the peripheral wall side and the outer surface of the rib on the frame-shaped portion side are in surface contact, The rib on the frame-shaped part side is stably supported by the rib on the peripheral wall side, the terminal is firmly locked in the bolt tightening direction, and is accurately positioned in the peripheral wall, and the locking to the locking part is strong Surely done.

  The screw tightening terminal locking structure according to claim 2 is the screw tightening terminal locking structure according to claim 1, wherein the frame-shaped portion and the outer surface of the rib on the frame-shaped portion side are curved surfaces. It is characterized by that.

  With the above configuration, the intersection between the frame portion of the terminal and the rib continues smoothly on the curved surface, so that when the terminal is inserted into the peripheral wall, the curved surface smoothly slides on the locking portion with a small frictional force. The terminals are smoothly inserted and locked.

  The screw tightening terminal locking structure according to claim 3 is the screw tightening terminal locking structure according to claim 1 or 2, wherein the peripheral wall comprises right and left and rear vertical wall portions, Each inner wall is formed inside the wall portion, each pair of vertical slits is provided in each inner wall, and the pair of locking portions are formed between the pair of slits, the left and right wall portions and the A bending space of the pair of locking portions is formed between the inner walls, a cover that covers the terminals is attached to the junction box body, and each protruding plate portion of the cover is placed in the bending space of the pair of locking portions. It is characterized by entering.

  With the above configuration, when the terminal is slidably inserted into the peripheral wall and the frame-like portion is engaged with the locking portion, the cover is removed when the insertion is incomplete and the locking portion is bent and stopped. When mounting on the junction box body, the protruding plate portion of the cover hits the locking portion, and the cover cannot be mounted. Thereby, the assembly operator can detect incomplete locking, and after the locking is completely performed, the cover is remounted. The terminal is inserted into the peripheral wall along the bus bar which is the counterpart circuit.

  According to the first aspect of the present invention, when the terminal is in the locked state, the frame-side rib is in contact with the peripheral wall-side rib by surface contact, so that the terminal is prevented from moving in the swing direction and the locking force is ensured. This prevents the terminal from coming off before bolting.

  According to the second aspect of the present invention, the terminal can be smoothly slidably contacted with the engaging portion with the curved surface, and can be easily engaged with a small force, and the assembling property of the terminal to the junction box body is improved. To do.

  According to the third aspect of the present invention, since the cover cannot be mounted when the terminal locking is incomplete, the terminal locking incompleteness is reliably detected, and the operator completely engages the terminal. By re-stopping, locking failure is prevented, thereby ensuring a contact area between the terminal and the bus bar which is the counterpart circuit, good electrical continuity is achieved, and the terminal due to insufficient insertion of the terminal Anxiety such as unexpected disconnection is eliminated, and the reliability of electrical connection is improved.

It is a disassembled perspective view which shows one Embodiment of the electrical-connection box containing the latching structure of the terminal for screw fastening which concerns on this invention. It is a perspective view of the assembly state which similarly shows the principal part of an electrical-connection box. It is a perspective view which shows the principal part of the flame | frame of an electrical junction box. It is a perspective view which shows the state which latched and screwed the terminal to the flame | frame. It is a top view which shows the state which similarly latched and screwed the terminal to the flame | frame. It is the perspective view of the state which looked at one form of the side cover for covering a terminal from the inner side. It is a perspective view which shows one form of the latching structure of the conventional screw fastening terminal.

  1 to 2 show an embodiment of an electrical connection box including a screw fastening terminal locking structure according to the present invention, and FIGS. 3 to 6 show an embodiment of a screw fastening terminal locking structure. Is.

As shown in FIG. 1, the electrical junction box 1 includes an insulating resin frame (a junction box body) 2, a fuse block 3 to be inserted inside the frame 2, and an opening 5 provided on a side wall 4 a of the frame 2. Screw fastening terminal 7 with electric wire 8 which is fastened and fixed with bolt 6 on the fuse block 3 side inside
And a side cover (cover) 9 made of insulating resin that closes the opening 5.

  The frame 2 has a rectangular frame-shaped vertical outer peripheral wall (enclosure wall) 4 and each accommodating portion (accommodating space) 11 penetrating vertically inside the outer peripheral wall 4 and partitioned by a partition wall. A part of the side wall 4a of the outer peripheral wall 4 is notched in the vertical direction to form an opening 5, and a pair of guide rails having a L-shaped cross section (guides) for slidingly engaging the side cover 9 from above on both ends of the opening 5 Part) (FIG. 2) 12 is formed to project outward. The fuse block 3 is accommodated and locked in each accommodating portion 11 from below, and an electronic board unit or the like (not shown) is accommodated from above.

  The fuse block 3 is connected between a block main body (junction box main body) 13 made of insulating resin, each bus bar 14 made of conductive metal inserted into the block main body 13 (only a part of which is shown), and the bus bar. Connected to fusible link 15, exposed horizontal plate portion (substitute with reference numeral 14) of bus bar (mating circuit) 14 arranged on terminal block 16 of block body 13, and clamping terminals (not shown) of each bus bar And a connector housing 17 for accommodating a tab terminal (not shown) of each bus bar.

  A nut (not shown) is accommodated inside the terminal block 16, and a bolt 6 is inserted from above into a hole provided in the plate portion of the bus bar 14 and temporarily tightened to the nut. In this state, the fuse block 3 is attached to the frame 2. The terminal block 16, the plate portion of the bus bar 14 and the bolt 6 are located inside the side opening 5 of the frame 2, and the plan view as a member in the opening 5 of the frame 2 is located above the terminal block 16. A substantially U-shaped peripheral wall 18 (FIGS. 2 and 3) is located, and a pair of left and right flexible locking pieces (locking portions) for locking the screw fastening terminal 7 inside the peripheral wall 18. 19 (FIG. 3) is provided.

  As shown in FIG. 3, the peripheral wall 18 is composed of right and left and rear vertical wall portions 22 to 24. A small rectangular opening 25 is provided on the front side of the peripheral wall 18, and the space inside the peripheral wall 18 is vertically and forwardly. It penetrates (communication), and the peripheral wall 18 is extended downward, along with the vertical wall 26 on the lower side of the front opening 25, and the horizontal upper wall 27 (see FIG. 2) inside the outer peripheral wall 4 (FIG. 2) of the frame 2. It crosses 2) and continues together. In the specification, the front / rear and left / right directions are for convenience of explanation.

  Inner walls 28 that are perpendicular to the inner sides of the left and right peripheral walls (outer walls) 22 and 23 are integrally formed, and the inner wall 28 and the outer walls 22 and 23 are connected by narrow front and rear end walls 29, and the inner wall 28 and the outer wall are connected. A gap 30 is formed between the inner wall 28 and the locking piece 19. That is, a pair of vertical slits 31 are provided in the portions near the rear walls of the left and right inner walls 28, and a flexible plate piece 20 that is a part of the inner wall 28 is formed between the pair of slits 31. A locking protrusion 21 is provided on the inner surface of the piece 20, and the locking piece 19 is constituted by the plate piece 20 and the protrusion 21. The plate piece 20 is formed slightly lower than the inner wall 28. The gap 30 acts as a bending space for the locking piece 19.

  The protrusion 21 has a front inclined surface (sliding contact guide surface) 21a, a rear vertical surface (locking surface) 21b, a lower steep inclined surface 21c, and an upper gentle inclined surface 21d. It is formed in a quadrangular pyramid shape, and the tip of the protrusion 21 protrudes inward and has a narrow top surface. The portion following the slit 31 near the rear wall 24 of the left and right inner walls 28 is a short vertical rib 32 protruding forward, and the rib 32 continues at the same height as the inner wall 28 and perpendicular to the rear wall 24. .

  In the state in which the fuse block 3 is assembled from below in the frame 2 of FIG. 1, the horizontal bus bar 14 on the terminal block 16 is located in contact with the lower side of the peripheral wall 18 as shown in FIGS. In the temporarily tightened state (a state where a terminal insertion gap exists between the bolt head 6a and the bus bar 14), the screw tightening terminal 7 slides along the upper surface of the bus bar 14 from the front opening 25 in a sliding manner. It is inserted into and locked by the left and right locking pieces 19.

  The screw terminal 7 includes a horizontal plate portion 33, a frame-like portion 34 raised vertically from the tip of the plate portion 33, and an electric wire connecting portion (crimped) that is bent downward from the base end of the plate portion 33. (Single part) 35. The plate portion 33 is formed with a wide distal end and a narrow proximal end, the lower surface of the plate portion 33 is in contact with the upper surface of the bus bar 14 in surface contact, and the left and right end surfaces 33a of the wide portion on the distal end side (second half) of the plate portion 33 Is in contact with the inner surface of the inner wall 28 with almost no gap.

  Further, the front end surface (rear surface) of the frame-shaped portion 34 is in surface contact with the inner surface of the rear wall 24, and the outer surface 35 a of the rib 35 folded back to the base end (front end) side of the frame-shaped portion 34 is formed on the rear wall 24. The inner surface of the orthogonal rib 32 and the inner surface of the inner wall portion 28a (FIG. 3) below the slit are stably in surface contact (at least with the inner surface of the rib 32), and the base end (front end) surface 35b of the rib 35 is locked. It contacts the vertical rear end surface (locking surface) 21b of the protrusion 21 by surface contact.

  The frame-shaped portion 34 is composed of an upward U-shaped frame main body and a rib 35. The frame main body includes a pair of left and right wide raised portions 34a raised vertically from a horizontal plate portion 33, and both standing A narrow connecting portion 34b that horizontally connects the upper ends of the raised portions 34a is formed. A vertical rectangular opening 36 for inserting a bolt head is formed inside the frame body, and the opening 36 is a horizontal plate portion. 33 is communicated with a slot 37 for bolt shaft insertion (FIG. 5).

  The rib 35 is folded at a right angle from the side end of the raised portion 34a toward the base end side (front side), and the outer surface (rear surface) of the raised portion 34a and the outer surface of the rib 35 are rounded curved surfaces (sliding guides). Surface) 35c smoothly connected. The ribs 35 increase the strength of the frame portion 34. Further, when the terminal 7 is inserted into the peripheral wall 18, the curved surface 35 c smoothly contacts the inclined surface 21 c at the front end of the locking projection 21 with a small sliding resistance, and the locking piece 19 is connected to the inner wall 28 and the outer wall 22. , 23 is smoothly bent outward in the gap 30 between them. Immediately after the rib 35 passes through the locking projection 21, the locking piece 19 is elastically restored, and the vertical front end surface 35b of the rib 35 abuts on the vertical locking surface 21b on the rear side of the projection 21 by surface contact. And is securely and securely locked.

  Since the frame-shaped portion 34 passes through the locking projection 21 with a small pressing force, there is no fear of the terminal 7 being incompletely locked, and the plate portion 33 of the terminal 7 and the bus bar 14 caused by insufficient pressing of the terminal 7 A reduction in contact area is prevented, and the reliability of electrical connection between the terminal 7 and the bus bar 14 is improved. The fear of the terminal 7 coming out due to vibration or the like after the bolt 6 is tightened (finally tightened) is also eliminated.

  Since the outer surfaces 35a of the left and right ribs 35 are in surface contact with the inner surfaces of the ribs 32 on the rear wall 24 side adjacent to the rear side of the left and right locking pieces 19, even if the terminal 7 is swung or twisted in the width direction. Even in this case, the force is received by the ribs 32 and 35 to prevent the terminal 7 from rotating (displacement). Thereby, the position of the terminal 7 is accurately defined, and the worry that the wire connecting portion 35 and the wire 8 (FIG. 1) interfere with the frame 2 and the like is solved.

  The electric wire 8 (FIG. 1) connected to the terminal 7 is connected to an alternator or a converter of the automobile. When the terminal 7 is removed from the bolt 6 for maintenance or the like, the bolt 6 is completely removed and the terminal 7 is lifted vertically, so that the horizontal plate portion 33 is lowered on the lower inclined surface 21c of the locking projection 21 (FIG. 3). ) And slidably contact with each other at a low force to be easily separated.

  As shown in FIG. 2, the side cover 9 is attached to the frame 2 with the terminals 7 assembled. As shown in FIG. 6, the side cover 9 enters a pair of projecting plate portions 39 suspended from the left and right ends of the horizontal upper wall 38 and the inside of the inner wall 28 (FIG. 4) of the frame 2. A frame wall 40 that is in contact with or close to the terminal plate portion 33 with the inner wall 28, a vertical outer wall 41 that continues integrally with the lower front side of the frame wall 40, and a frame wall that obliquely intersects the inside of the outer wall 41. 40 and an inner wall 42 that continues to 40. The outer wall 41 has a bulging portion 43 for leading out the electric wire, and the inner wall 42 has a slide engaging portion 45 for the short guide portion 44 on the frame upper wall 27 (FIG. 2) side.

  As shown in FIG. 2, the pair of plate pieces 39 enters and engages with the gap 30 in the peripheral wall 18 of FIG. 4 to prevent the locking piece 19 from being bent outward. Thereby, the latching of the terminal 7 after bolt fastening is reliably maintained. In the unlikely event that the insertion of the terminal 7 into the peripheral wall 18 is incomplete, the locking projection 21 hits against the rib 35 of the terminal 7 and the locking piece 19 is bent outward, the side cover 9 is closed. Even if it tries to do so, the lower end of the projecting plate portion 39 abuts against the locking piece 19, and the side cover 9 cannot be closed (assembled to the frame 2), so that the locking of the terminal 7 is detected. The operator pushes the terminal 7 again into the peripheral wall 18 and securely locks it to the locking piece 19, so that incomplete locking of the terminal 7 is reliably prevented. The electric wire 8 (FIG. 1) following the terminal 7 is guided downward along the bulging portion 43 of the side cover 9 without interference.

  In FIG. 1, the fuse block 3 is assembled in the frame 2, and a terminal 8 with an electric wire is inserted from the side opening 5 of the frame 2 along the bus bar 14 on the fuse block side, and is engaged by a locking piece 19 of the frame 2. The terminal 7 is fixedly connected (fixed) to the bus bar 14 by fastening the bolt 6, the side cover 9 is attached to the opening 5 along the guide rail 12 of the frame 2, and the fuse block 3 is attached from above the frame 2. An electronic board unit or the like (not shown) is assembled to the connector, and a connector or the like (not shown) with electric wires is connected from above and below, and a cover (only the lower cover 46 is shown in FIG. 2) is provided above and below the frame 2. The electrical connection box 1 is configured by being attached.

  The configuration of the present invention described above includes the block portion 3, the frame 2 that houses the block portion 3, and the side cover 9 that covers the side opening 5 of the frame 2, in addition to the locking structure of the screw fastening terminal. It is also effective as the electrical connection box 1 having.

  Moreover, it is also possible to use a relay block, a connector block, etc. instead of the fuse block 3 in the said embodiment. These fuse block 3, relay block, connector block and the like can be collectively referred to as an electrical connection block.

  Further, in FIG. 4, for example, the inner fuse block 3 and the outer frame 2 are integrally formed or regarded as a single body, and the insulating resin frame 2 and the fuse block main body 13 are used as a connection box main body, and connected. The terminal 7 is inserted into the U-shaped peripheral wall 18 of the connection box main body while being brought into contact with the bus bar 14 along the box main body, locked with the locking piece 19, and finally tightened with the bolt 6. It is also possible to do. Instead of the bus bar 14, another terminal, a resin integrated molding circuit, or the like (not shown) can be used as a counterpart circuit to be screwed to the terminal 7.

  The locking structure of the screw fastening terminal according to the present invention prevents incomplete engagement between the terminal and the locking portion of the junction box body, and securely locks (temporarily fixes) the terminal to the locking portion, Further, the terminal can be used to engage the locking portion smoothly and firmly with good workability.

2 Frame (Junction box body)
6 bolt 7 terminal 9 side cover (cover)
14 Busbar (partner circuit)
18 Perimeter wall 19 Locking piece (locking part)
22-24 Wall part 28 Inner wall 30 Crevice (flexure space)
31 Slit 32 Rib 34 Frame-shaped part 35 Rib 35c Curved surface 39 Projecting plate part

Claims (3)

A junction box body made of insulating resin is provided with a peripheral wall for storing terminals and a pair of flexible locking portions in the peripheral wall, and a frame-shaped portion for inserting a bolt head of a terminal with an electric wire in the peripheral wall Is locked by the pair of locking portions, and the terminal is screwed and connected to the mating circuit,
A pair of ribs are provided on the peripheral wall adjacent to the pair of locking portions, and a pair of ribs are provided on both sides of the frame-shaped portion. A locking structure for a screw fastening terminal, wherein the outer surface of the rib on the frame-like portion side contacts.   The locking structure for a screw fastening terminal according to claim 1, wherein the frame-shaped portion and the outer surface of the rib on the frame-shaped portion side are curved surfaces.   The peripheral wall is composed of right and left and rear vertical wall portions, each inner wall is formed inside the left and right wall portions, and each pair of vertical slits is provided on each inner wall, between each pair of slits. The pair of locking portions is formed, a bending space of the pair of locking portions is formed between the left and right wall portions and the inner walls, and a cover that covers the terminals is attached to the junction box body. 3. The screw fastening terminal locking structure according to claim 1, wherein each protruding plate portion of the cover enters the bending space of the pair of locking portions.

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