JPS596034B2 - electric fuel - Google Patents

Description

[Detailed description of the invention] The present invention relates to electrical crimping ferrules.

Applicant's patent number 597386 (Japanese Patent Publication No. 45-208
70), the inner surface of the ferrule is provided with a series of grooves forming saw-tooth incisions extending transversely with respect to the longitudinal axis of the ferrule, each groove connecting the floor and the first and second side walls. the first side wall faces in the axial direction of one of the ferrules, the second side wall faces in the opposite direction of the first side wall, and in the axial cross section of the ferrule, the second side wall faces in the longitudinal direction of the ferrule. An electrically crimped ferrule is disclosed having an equal constant angle with respect to the axis of the ferrule and in which the depth into which successive grooves or groups of grooves extend into the material of the ferrule progressively decreases in the axial direction.

The serrations act to break down the insulation when the ferrule is crimped to the wire to form a good electrical bond between the crimped ferrule and the wire.

In particular, from ferrule strips whose ends are joined by a slug of ferrule material, with a shear blade or shear plate used during the crimping operation holding down one end of the ferrule, i.e. preventing movement of the ferrule in one longitudinal direction. When cutting a ferrule apart, the force exerted by the wire against the sawtooth cut has a significant lateral or axial component, which is directed away from the depressed end of the ferrule. This has the effect of not only bending the saw-toothed cuts laterally, but also causing incomplete biting of the wire material into the grooves between the saw-toothed cuts. , such an effect increases strongly in the direction away from the pressed end of the ferrule. In the case of the above-mentioned known ferrule, the first side wall of the groove has an equal angle with the second side wall, so that the connection between the wire and the ferrule results from the above-mentioned axial force component. It is compromised by the lateral bending of the saw-tooth cut and the creation of voids in the groove. Such a force component also occurs even if one end of the ferrule is not pressed due to, for example, incomplete crimping. The present invention seeks to eliminate the drawbacks of such conventional ferrules,
According to one characteristic of the crimping ferrule of the present invention, compared to the ferrule disclosed in the above-mentioned patent No. 597386,
The first side wall is characterized by increasing separation from the second side wall in one axial direction outwardly of the groove.

Therefore, the crimping ferrule of the present invention is disclosed in the aforementioned Patent No. 5.
Unlike the ferrule of No. 97386, since the angle of the first side wall of the groove increases gradually in the axial direction of the ferrule, the width of the effective base of each tooth of the serrated notch, The strength also increases, and eventually the groove becomes deeper? decreases in the axial direction, so the strength increases even more.

Therefore, the saw-toothed notch has the advantage of being able to withstand lateral bending forces that gradually increase from one pressed end of the ferrule to the other free end. Further, as mentioned above, by gradually increasing the angle of the first side wall of the groove,
This has the advantage that the wire material is gradually pressed into the groove and comes into complete contact with the walls and floor of the groove, leaving no voids.

The crimping ferrule of the present invention is particularly used for varnish insulated wires, but is not used for the ferrule-based varnish insulated wires of the above-mentioned Japanese Patent No. 597386.

Applicant's British Patent No. 754493
Is the ferrule disclosed in 1265 compatible with varnish insulated wire used? Although it has internal serrations and serrations, it cannot achieve the advantages of the invention described above since all serrations have equal cross-sections.

In addition, in the crimping ferrule of the present invention, when using a ferrule that matches the planned dimensions of the electric wire, the electric wire can be cut by the sawtooth cut on the longer side, that is, the one closest to the pressed end of the ferrule. A significant advantage is that the apexes of all serrations are equidistant from the longitudinal axis of the ferrule to avoid damage. The present invention provides that even if the wire is cut by the longer sawtooth cut, there is still a portion of the wire that is not cut, so that the shorter sawtooth achieves a good electrical connection. , it has the advantage that a longer electric wire can be used than the electric wire adapted to the ferrule used.

If the angle of the sidewall facing the pressed end of the ferrule is approximately 1000 to the floor of the groove and the angle of the remaining sidewall is approximately 10σ to 1200 to the floor of the groove, then It is known that similar results can be achieved.

Therefore, according to another characteristic of the crimping ferrule of the invention, the floors of the grooves are parallel to each other and the angle of the first side wall is approximately between 100 and 1200 with respect to the floor. , the second sidewall has an angle of about 1 with respect to the floor.
In front of 00, V1 is the thickness of the saw v tooth-shaped notch? increases gradually in the axial direction in the axial cross-section of the ferrule, and the tops of the serrated notches are equidistant from the longitudinal axis of the ferrule.

FIG. 1 shows the crimp ferrule 10 before insertion of the wires to be spliced. The ferrule 10 has side walls 13 and 14 that are generally U-shaped in cross section and rise from opposite sides of a bottom portion 16 forming a recess 11 for receiving the V1 wire. The expanded shape of the ferrule is approximately rectangular. The ferrule 10 is joined by a metal slug 18 to the next similar ferrule (not shown) in the strip of ferrule 10.

The strips form a series of ferrules of an end-to-end type. A series of grooves 20, 21 formed in the inner surface of the ferrule 10 to form saw-toothed notches.
, 22, 23, 24, 25, 26, 27} and 28 are
In a direction perpendicular to the longitudinal axis of ferrule 10, wall 13
and 14 and extend continuously across the bottom 16 . Each groove has two opposing side walls projecting from the floor, and the floors of all grooves are parallel to each other. Figure 2 shows
1 previously placed in the recess 11 so as to extend in the axial direction.
Tools (not shown) for pair of varnish insulated wires 30 and 31
The ferrule 10 is shown after being crimped.

In order to separate the ferrule from the ferrule strip using a conventional shearing tool (not shown) including a shearing blade, during the crimping operation, the shearing blade held one end of the ferrule stationary and the slug 18 was cut off. . As a result of the crimping operation,
Walls 13 and 14 are rolled up (as shown in Figure 2)
, substantially surrounding wires 30 and 31, respectively. Also, during the crimping operation, the insulation of the wires 30 and 31 is stripped from the conductive core of the wire by the action of the saw-toothed cuts, but the insulation debris (not shown) is removed from the core of the wire. It remains between the inner surface of the ferrule and the inner surface of the ferrule. As shown in Figure 3, grooves 20, 21, 22, 23, 24, 25, 2
The shapes of ferrules 6, 27, and 28 change from groove to groove in the axial direction of the ferrule, and extend from the left end (in FIG. 3) to the right end (in FIG. 3) of the ferrule 10. As a result, the depth of the groove gradually decreases.

That is, the extent to which it bites into the ferrule material is reduced.
That is, the floor 40 of the groove 20 is deeper than the floor 41 of the next adjacent groove 21, and the floor 41 of the groove 21 is deeper than the floor 42 of the next adjacent groove 22.
The same applies below. The last groove on the right axis 28
The floor portion 45 of the is shown in FIG.
21, 22, 23, 24, 25, 26, 27 and 28
It is at the shallowest position in the But formed by grooves?
Tops of sawtooth cuts 60, 61, 62, 63
, 64, 65, 66 and 67 are all on the same inner surface V1, ie they are all equidistant from the longitudinal axis of the ferrule. In practice, the depth of the grooves may vary from group to group of grooves.

For example, are grooves 20, 21, and 22 all the same depth?
Grooves 23, 24, and 25 are somewhat shallower, but are all the same depth, and grooves 26, 27, and 28 are the shallowest, but they are also all the same depth. As shown in FIG. 3, while crimping the ferrule 10, a compressive force is created in the groove 20 directed perpendicular to the longitudinal axis of the ferrule, as indicated by arrow 48, and such The force tries to force the wire into this groove.

However, as described above, since the left side of the ferrule is held down by the shearing blade, the compressive force generated by the crimping tool has a lateral component that increases from left to right along the ferrule. This will be apparent by comparing arrow 48 with arrow 50, which indicates the compressive force at the right end of the ferrule. Since the depth ▲ of the floor of the groove decreases toward the right (in FIG. 3), the material of the wire 30 is pressed into the groove while decreasing toward the right of the ferrule. This reduced groove depth provides optimal surface contact between the wire and ferrule and therefore optimal electrical connection between them. As shown in FIG.
7 and a sawtooth 9 tooth-shaped incision with grooves is generally trapezoidal and the apex portions 60, 61, 62, 63, 64,
65, 66 and 67 are all equidistant from the longitudinal axis of the ferret.
(See Figure 3) The side walls make approximately the same angle with the floor of the groove and the longitudinal axis of the ferrule.

The right side wall 70, 71, 72, 73, 74, 75, 76
, 77 and 78 are all approximately 1 d' with respect to the vertical (in Figure 3) or 10 with respect to the floor of the groove.
He is a male. However, this angle may also be between e and 1 with respect to the vertical and between 9 and 10 with respect to the longitudinal axis of the ferrule. First or left side wall 80 of the groove
, 81, 82, 83, 84, 85, 86, 87 and 8
8 has progressively increasing angles from the left to the right of the ferrule with respect to the vertical (in Figure 3) or the floor of the groove; these angles are relative to the vertical as in the case of groove 20. Approximately 10 degrees (from 10 (j') to the floor of the groove,
30) relative to the vertical in the case of groove 28 (1200 relative to the floor of the groove).

Therefore, the side walls 80, 81, 82, 83, 84, 85, 8
6, 87 and 88 extend outwardly from the groove, side walls 70, 71, 72, increasing successively in the right axial direction of the ferrule.
Stay away from trigrams 73, 74, 75, 76, 77 and 78.
These angles are, for example, plus and minus 5. , but must in any case increase to the right (in Figure 3). Side walls 80, 81, 82
, 83, 84, 85, 86, 87 and 88, from left to right, the wire material is pressed into the groove and makes full surface contact with the side walls and their floor. It gets easier as you progress.

Also, side walls 80, 81, 82, 83, 84, 85, 86
. The strength of the cuts increases one after another from left to right. Also, since the strength increases with a decrease in the depth of the groove to the right, the saw-toothed notch extends towards its open end, i.e. the right end (in FIG. 3) of the pressed end of the ferrule. can withstand increasing lateral forces from the Groove 20,2
1, 22, 23, 24, 25, 26, 27 and 28 may be formed by drawing a plurality of sharp tipped tools across the face of the sheet metal blank forming ferrule 10.

By using these tools, grooves 20 and 2
Formed by 1? Typically, protrusions 90 and 91, shown in FIG. 3, are formed on either side of the top 60 of the saw-toothed notch. Although a by-product of grooving, these protrusions are desirable in that they assist in cutting through the wire insulation and form contact points or lines with the wire core. As can be seen in FIG.
As a result of successively increasing the angles of and 88, the wire material can fully penetrate into the groove.

The particular groove depth and sidewall angle will depend on the wire dimensions and material. Is the groove shown above, as shown in the illustration, as if one end of the crimping ferrule was not pressed down during the crimping operation? The present invention can be usefully applied to ferrules other than simple wire splicing ferrules.

The reason is that commonly used crimping tools tend to produce uneven or non-orthogonal crimping forces, which in turn produces lateral forces that increase towards one end of the ferrule. . However, in this case, the ferrule will not be held down at one end, so the deep groove will be shallower than described above. The fact that the depth of the groove decreases towards one end of the crimp ferrule allows the use of larger wire dimensions than would be possible if such a fact did not exist.

The reason is that even if the wire is cut by the larger sawtooth cut, it will not be cut by the smaller sawtooth cut, so that good contact can be obtained between the wire and the ferrule.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the electrical crimping ferrule, Fig. 2 is a partial cross-sectional perspective view showing the ferrule of Fig. 1 when crimped to an electric wire, and Fig. 3 is an axial sectional view taken along the line - in Fig. 2. It is. 10... Ferrule, 20, 21, 22, 23, 24
, 25, 26, 27, 28... Groove, 80, 81, 8
2, 83, 8485, 86, 87, 88... first side wall, 7071, 72, 73, 74, 75, 76, 777
8... second side wall, 40, 41, 42, 43, 44,
45...floor, 60, 61, 62, 6364, 65,
66, 67...Top of sawtooth cut.

Claims (1)

Claims: 1. The ferrule has a series of grooves forming serrations extending transversely with respect to the longitudinal axis of the ferrule, each groove connecting the floor and the first and second side walls. , the first side wall faces in the axial direction of one of the ferrules, the second side wall faces in the opposite direction of the first side wall, and the ferrule has a cross section in the axial direction of the ferrule. In an electrical crimp ferrule having equal and constant angles with respect to the longitudinal axis and in which the depth into which successive grooves or groups of grooves extend into the material of the ferrule decreases progressively in the axial direction; One side wall 80, 81, 82, 83, 84, 85, 86, 87, 8
8 is the second side wall 70, 71, 72, 73, 74, 7
5, 76, 77, 78 to the grooves 20, 21, 22,
23, 24, 25, 26, 27, 28, the electric crimp ferrules are separated outwardly in the axial direction so as to gradually increase in distance. 2. the inner surface of the ferrule has a series of grooves forming serrated notches extending transversely with respect to the longitudinal axis of the ferrule, each groove having a floor and first and second sidewalls;
the first side wall faces in the direction of one axis of the ferrule, the second side wall faces in the opposite direction of the first side wall, and with respect to the longitudinal axis of the ferrule in an axial cross section of the ferrule; The depth of the groove or groups of grooves having equal and constant angles and extending into the material of the ferrule progressively decreases in the axial direction so that the first side wall extends from the second side wall. In the electric crimp ferrule which gradually increases apart in the axial direction toward the outside of the grooves, the grooves 20, 21, 2
2, 23, 24, 25, 26, 27, 28 floor parts 40,
41, 42, 43, 44, 45 are parallel to each other, and the first side walls 80, 81, 82, 83, 84, 85, 86
, 87, 88 are the angles of the floor portions 40, 41, 42, 43.
, 44, 45, said second side walls 70, 71, 72, 73, 74,
The angles 75, 76, 77, and 78 correspond to the floor portions 40, 41,
42, 43, 44, 45, and the thickness of the serrated notch gradually increases in the axial direction in the axial section of the ferrule 10, and the crest of the serrated notch 60, 61, 62, 63, 64
, 65, 66, 67 are equidistant from the longitudinal axis of the ferrule.