JP5856797B2 - Tuning fork terminal - Google Patents

Description

  The present invention relates to a tuning fork terminal suitable for use in, for example, a fuse cavity of an electric junction box of a vehicle.

4 and 5 show a conventional fuse cavity and an electric junction box (see, for example, Patent Document 1).
As shown in FIG. 4, the blade-type fuse 60 includes a fuse element (fuse body) 61 in which a fusible portion 65 is connected between a pair of flat plate terminal portions 63, 63 arranged on a plane, and a fuse element 61 is possible. It comprises an insulating housing 64 that covers the melting portion 65 and has an insulating property for fixing the flat terminal portion 63.

By mounting the fuse 60 in the fuse cavity 78 of the electrical connection box 70, the tuning fork terminal 71 provided in the fuse cavity 78 and the flat terminal portion 63 of the fuse 60 are brought into contact with each other so as to be energized.
As shown in FIG. 5, the tuning fork terminal 71 is formed by pressing a slot 74 for pressure contact integrally by cutting vertically from the center of the front end of the vertical portion where the end of the bus bar 79 is bent vertically. The contact portions 73 and 75 protrude from the opposite end surfaces of the pair of sandwiching pieces 72 and 72 formed by the above.

When the flat plate terminal portion 63 of the fuse 60 which is the counterpart terminal is connected to the tuning fork terminal 71, the flat plate terminal portion 63 is inserted into the vertically long slot 74 of the tuning fork terminal 71 and is sandwiched and connected to the slot 74. The fuse 60 and the bus bar 79 are connected to be energized.
As shown in FIG. 4, the blade-shaped fuse 60 mounted in the fuse cavity 78 is inserted into the fuse cavity 78 by the lower end edge 64 a of the insulating housing 64 abutting against the upper end of the insulating wall 76 of the fuse cavity 78. Positioning is performed.

JP 2002-163974 A

  However, the insertion position of the fuse 60 mounted in the conventional fuse cavity 78 described above is difficult to accurately position due to a molding error of the fuse cavity 78, an assembly error of the bus bar 79 to the fuse cavity 78, and the like. There is a problem that it is difficult to accurately press contact the contact portions 73 and 75 to a predetermined position of the flat plate terminal portion 63.

  Furthermore, when inserting and positioning with respect to the tuning fork terminal 71 by bringing the lower end edge of the flat terminal portion 63 into contact with the crotch bottom 77, the lengths of the pair of sandwiching pieces 72, 72 forming the slot 74 are adjusted. There is a need. However, for example, if the clamping piece 72 is shortened, it becomes difficult to maintain the spring property for clamping and connecting the flat terminal portion 63 in the thickness direction. On the other hand, if the holding piece 72 is lengthened, the length in the insertion direction of the flat terminal portion 63 must be increased, which causes a problem that the fuse 60 is enlarged.

  Further, in the conventional tuning fork terminal 71 described above, the two contact points 73 and 75 that protrude from the opposite end surfaces of the slot 74 are contact points with the flat plate terminal 63. Therefore, since the contact area between the tuning fork terminal 71 and the flat terminal portion 63 is small, there is a problem that the electric resistance increases and heat is easily generated by Joule heat.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a tuning fork terminal capable of mounting the flat terminal portion of the mating terminal at an appropriate insertion position and reducing electric resistance to the flat terminal portion. It is to provide.

The above object of the present invention is achieved by the following configuration.
(1) It has a vertically long slot formed at the tip of a flat terminal body extending perpendicularly to the upper edge of a pair of bus bars housed in the fuse cavity of the electrical junction box , and is inserted into the slot. A tuning fork terminal that sandwiches and connects the flat plate terminal portion of the fuse to the slot, and is provided with at least two contact portions that sandwich and connect the flat plate terminal portion in the plate thickness direction on both opposing end faces of the slot, At least one side end surface inward of the slot by a distance approximately half the length of the flat plate terminal portion in the insertion direction from the contact portion, the flat plate terminal portion is brought into contact with the lower end edge of the flat plate terminal portion. A positioning contact portion for making electrical contact with the fuse and positioning the fuse is provided.

According to the tuning fork terminal having the configuration (1), the positioning contact portion provided on the one side end surface of the slot can contact the flat terminal portion of the mating terminal inserted into the slot, thereby performing insertion positioning. . Therefore, the contact portion that sandwiches and connects the flat plate terminal portion can be accurately pressed against a predetermined position of the flat plate terminal portion.
Further, the tuning fork terminal can be in electrical contact with the flat plate terminal portion of the mating terminal at the contact portion for positioning in addition to the two contact portions provided on the opposite end faces of the slot. The electrical resistance between the terminal portions can be reduced.
Further, the positioning contact portion can be formed integrally with the slot of the tuning fork terminal, and can be formed by simple press molding.

In addition, it is possible to reliably maintain a good electrical connection between the flat plate terminal portion of the fuse mounted in the fuse cavity and the bus bar, and to provide an electrical connection box in which the fuse can be mounted in a stable state. .

  According to the tuning fork terminal of the present invention, the flat terminal portion of the mating terminal can be mounted at an appropriate insertion position, and the electrical resistance to the flat terminal portion can be reduced.

  The present invention has been briefly described above. Furthermore, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

It is a perspective view which shows the tuning fork terminal and fuse which concern on one Embodiment of this invention, (A) is a principal part disassembled perspective view, (B) is a perspective view which shows the state which mounted | wore the tuning fork terminal shown to (A). FIG. It is a disassembled perspective view of the fuse shown in FIG. FIG. 2 is a side view of the tuning fork terminal and the fuse shown in FIG. It is principal part sectional drawing which shows the state which attached the fuse to the conventional tuning fork terminal. FIG. 5 is a side view of the tuning fork terminal and the fuse shown in FIG. 4.

Hereinafter, a tuning fork terminal according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in FIGS. 1 and 3, the tuning fork terminal 50 according to the present embodiment is a front end of a flat terminal body that extends perpendicularly to the upper edges of a pair of bus bars 59 housed in a fuse cavity of an electrical junction box. This is a terminal that has a vertically elongated slot 54 formed in a notch, and sandwiches and connects the flat plate terminal portion 41 of the fuse 10, which is a mating terminal inserted into the slot 54, to the slot 54.

  Two contact portions 53 and 55 for sandwiching and connecting the flat plate terminal portion 41 in the plate thickness direction project from the opposite end faces of the slot 54, and the slot 54 is located inwardly of the slot 54 (in the drawing). A positioning contact portion 57 for projecting and positioning the fuse 10 by contacting the lower end edge of the flat plate terminal portion 41 protrudes from one side end face in the lower side.

  That is, the tuning fork terminal 50 is formed by press-molding a press-contacting slot 54 integrally at the front end of a flat-plate-like terminal body extending perpendicularly to the upper end edge of the bus bar 59 by means of the slot 54. The contact portions 73 and 75 project from the opposite side end surfaces of the pair of sandwiching pieces 51 and 52, respectively, and the positioning contact portions 57 project from the side end surfaces of the sandwiching piece 51. .

  The positioning contact portion 57 provided on the tuning fork terminal 50 according to the present embodiment has a horizontal surface on the upper surface (the contact surface) facing the lower end edge of the flat plate terminal portion 41 inserted into the slot 54, and the lower end edge of the flat plate terminal portion 41. The fuse 10 can be inserted and positioned by abutting against.

As shown in FIG. 2, the fuse 10 sandwiched and connected to the slot 54 of the tuning fork terminal 50 is a fuse roughly divided into a fuse element (fuse body) 40 and upper and lower cases (insulating housings) 20 and 30. It is.
The fuse element 40 is provided with a substantially band-shaped band-shaped connecting portion 42 having a fusible portion 49 formed by gripping a low melting point metal chip 47 between parallel inner edges 41a of the pair of flat plate terminal portions 41, 41. Yes. The fuse element 40 includes a flat plate terminal portions 41 and 41 connected to an electric circuit, and a strip-shaped connecting portion 42 that electrically connects them, for example, a metal plate whose base material is copper (Cu), aluminum (Al), or the like. It is integrally formed by press molding.

  The band-shaped connecting portion 42 is narrowed so that it can be easily melted based on predetermined fusing characteristics. That is, the rated current capacity of the fuse 10 can be changed by changing at least one of the conductivity of the fuse element 40 and the extraction width of the belt-like connecting portion 42 having the fusible portion 49. Thereby, it is possible to change to an appropriate fuse characteristic (rated current capacity) according to each of the fuses 10 having different specifications while maintaining the same outer shape. That is, the fuse 10 does not increase in product size in accordance with the rated current capacity.

  The belt-like connecting portion 42 is formed with a soluble portion 49 including a pair of support pieces 45. The support pieces 45 extend in the width direction of the belt-like connecting portion 42, and the low melting point metal chip 47 having a melting point lower than that of the fuse element 40 is fixed to the fusible portion 49 by crimping by the support pieces 45. The low melting point metal chip 47 is made of a low melting point metal such as tin (Sn) or a tin alloy having a melting point lower than that of copper or the like which is a base material constituting the flat terminal portion 41 or the strip-shaped connecting portion 42.

Therefore, when an overcurrent flows through the belt-like connecting portion 42, the fuse element 40 has a so-called time lag until fusing by ensuring that the heat generated by the fusible portion 49 is absorbed by the low melting point metal chip 47. It constitutes a delayed fuse.
That is, in a load circuit such as an electric motor, instantaneous transient current that reaches several times the steady load current value flows at the start-up, and in a power window motor, it is steady when the window glass is fully closed or when the motor is locked. Since a motor lock current that reaches several times the load current value flows, a current that exceeds the steady current value frequently flows even when there is no abnormality such as a circuit short. Therefore, by using the above-described fuse element 40, the instantaneous transient current exceeding the steady current value, the motor lock current, etc. are not blown out, and the fuse element 40 is blown out quickly and surely excessively. The current can be cut off.

The upper and lower cases 20 and 30 according to the present embodiment are integrally formed of an insulating semi-transparent synthetic resin material.
As shown in FIG. 2, the substantially rectangular upper case 20 has a fusing part accommodating space 29 that accommodates the fusible part 49 and a window 21 that allows the fusible part 49 to be viewed from the outside. It is formed. A pair of engagement pieces 23 are extended on the upper and lower surfaces of the upper case 20 in the case mounting direction (rightward direction in FIG. 2), and are locked and engaged with engagement protrusions 33 of the lower case 30 described later. Further, four circular through holes 25 are formed at the four corners of the upper case 20, and a fixing column 35 of the lower case 30 described later is inserted.

  Four fixing pillars 35 project from the fuse mounting surface of the substantially rectangular lower case 30. When the lower case 30 is mounted on the back surface side of the fuse element 40, these fixed pillars 35 penetrate through the through holes 44 formed in each of the pair of flat plate terminal portions 41. Further, when the upper case 20 is mounted on the front surface side of the fuse element 40 so as to cover the inner edge 41 a and the fusible portion 49 of the flat terminal portion 41, the insertion tip of the fixing column 35 is the through hole 25 of the upper case 20. Inserted into. The upper and lower cases 20, 30 mounted from the front and back sides of the fuse element 40 are integrally coupled by engaging the engagement pieces 23 of the upper case 20 with the engagement protrusions 33 of the lower case 30.

  Thereby, the mounting operation | work which mounts the upper and lower cases 20 and 30 to the fuse element 40 becomes easy, and productivity can be improved. In addition, since the upper and lower cases 20 and 30 reliably cover the fusible portion 49 of the fuse element 40, adverse effects on other fuses 10 and the like due to scattering of fusing debris are prevented.

Next, an operation when the fuse 10 is attached to the tuning fork terminal 50 according to the present embodiment described above will be described.
As shown in FIG. 1, the electrical connection between the tuning fork terminal 50 and the flat plate terminal portion 41 of the fuse 10 is performed by inserting the flat plate terminal portion 41 into the slot 54 from the upper end of the tuning fork terminal 50 and contacting the front and back surfaces of the flat plate terminal portion 41. This is done by pressing the parts 53 and 55 together.

  As shown in FIG. 3, the flat plate terminal portion 41 of the fuse 10 inserted into the slot 54 of the tuning fork terminal 50 is inserted and positioned as the lower end edge contacts the upper surface of the positioning contact portion 57. Therefore, the contact portions 53 and 55 that sandwich and connect the flat terminal portion 41 can be accurately pressed into a predetermined position of the flat terminal portion 41. As a result, the fuse 10 has a good support balance in the fuse cavity, and blurring after the mounting is suppressed, and a good electrical connection can be reliably maintained.

  Further, the insertion and positioning of the flat terminal portion 41 only needs to adjust the protruding position of the positioning contact portion 57, so that it is not necessary to adjust the length of the pair of clamping pieces 51 and 52 forming the slot 54. . Therefore, it is difficult to maintain the spring property for sandwiching and connecting the flat terminal portion 41 in the plate thickness direction, or the length of the flat plate terminal portion 41 in the insertion direction must be lengthened, and the fuse 10 is enlarged. There is nothing to do.

Further, the tuning fork terminal 50 is in electrical contact with the flat plate terminal portion 41 of the fuse 10 at the positioning contact portion 57 in addition to the two contact portions 53 and 55 provided on the opposite end surfaces of the slot 54. Thus, a stable electrical connection with the flat terminal portion 41 can be realized and the electrical resistance can be reduced. As a result, the tuning fork terminal 50 can obtain high connection reliability with the fuse 10 and can suppress heat generation due to Joule heat.
Furthermore, the positioning contact portion 57 can be formed integrally with the slot 54 of the tuning fork terminal 50, and can be formed by simple press molding.

That is, according to the tuning fork terminal 50 described above, the flat plate terminal portion 41 of the fuse 10 can be mounted at an appropriate insertion position, and a stable electrical connection to the flat plate terminal portion 41 is realized and the electric resistance is reduced. Can be reduced.
Therefore, according to the tuning fork terminal 50 of the present embodiment, it is possible to reliably maintain a good electrical connection between the flat plate terminal portion 41 of the fuse 10 mounted in the fuse cavity and the bus bar 59 in a stable state. An electrical junction box in which the fuse 10 can be mounted can be provided.

The tuning fork terminal of the present invention is not limited to the above-described embodiment, and can be appropriately modified and improved. In addition, the material, shape, dimensions, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.
For example, in the above embodiment, the positioning contact portion 57 protrudes from the side end surface of the sandwiching piece 51, but the positioning contact portion 57 protrudes so as to face both end surfaces of the sandwiching pieces 51 and 52. May be. Further, the shape of the positioning contact portion 57 is not limited to the substantially rectangular shape of the above-described embodiment as long as it can be inserted and positioned by contacting the lower end edge of the flat plate terminal portion. Needless to say, the shape can be taken.

10 ... Fuse (mating terminal)
20 ... Upper case 30 ... Lower case 40 ... Fuse element 41 ... Flat plate terminal portion 50 ... Tuning fork terminal 51 ... Holding piece 52 ... Holding piece 53 ... Contact portion 54 ... Slot 55 ... Contact portion 57 ... Positioning contact portion 59 ... Bus bar

Claims (1)

A flat plate of a fuse inserted into the slot having a vertically elongated slot formed at the tip of a flat terminal body extending perpendicularly to the upper edge of a pair of bus bars housed in a fuse cavity of an electrical junction box A tuning fork terminal that sandwiches and connects the terminal portion to the slot,
At least two contact portions that sandwich and connect the flat plate terminal portion in the plate thickness direction are provided on opposite end surfaces of the slot,
At least one side end surface inward of the slot by a distance approximately half the length of the flat plate terminal portion in the insertion direction from the contact portion, the flat plate terminal portion is brought into contact with the lower end edge of the flat plate terminal portion. A tuning fork terminal comprising a positioning contact portion for making electrical contact with the fuse and positioning the fuse .

Images