WO2012124824A2

WO2012124824A2 - Press-contact blade

Info

Publication number: WO2012124824A2
Application number: PCT/JP2012/057410
Authority: WO
Inventors: Takahiro Hori
Original assignee: Yazaki Corp
Current assignee: Yazaki Corp
Priority date: 2011-03-16
Filing date: 2012-03-15
Publication date: 2012-09-20
Anticipated expiration: 2013-09-16
Also published as: JP2012195136A; WO2012124824A3

Abstract

A press-contact blade includes a slot for press-fitting therein a covered electric wire in which a core wire is covered with an insulative cover and a pair of slot-edge parts that defines the slot therebetween. One slot-edge part includes a first cut-out part located at a leading edge of the press-contact blade and a first straight part located at a deeper side of the slot than the first cut-out part. The other slot-edge part includes a wire-pressing part that faces the first cut-out part, a second cut-out part located at a deeper side of the slot than the wire-pressing part, and a second straight part located at a deeper side of the slot than the second cut-out part. The second cut-out part protrudes toward the one slot-edge part more than the wire-pressing part does.

Description

DESCRIPTION

PRESS-CONTACT BLADE Technical Field

The present invention relates to a press-contact blade which is provided in a terminal fitting or a bus bar so as to electrically connect the press-contact blade to a covered electric wire. Background Art

Fig. 8 is a cross-sectional view showing a state in which a

press-contact blade in a related art press-contacts with a covered electric wire. Fig. 9 is a cross -sectional view showing a state before the covered electric wire shown in Fig. 8 is press-fitted into a slot of the press-contact blade (refer to Patent Literature l).

A press-contact blade 332 shown in Figs. 8 and 9 is electrically connected to a covered electric wire 310. The press-contact blade 332 is provided in a terminal fitting 330 attached to a housing 351. The terminal fitting 330 is obtained, for example, by press-working a metal plate. The covered electric wire 310 is a circular cross-sectional electric wire in which a conductive core wire 311 is covered with an insulative cover 313.

A slot 333 is provided in a center part in a width direction of the press-contact blade 332 to open at an upper edge. The width of the slot 333 is smaller the diameter of the core wire 311 of the covered electric wire 310. At the upper end (or entrance) of the slot 333 is provided a guide part 335 that expands the entrance upwardly.

The covered electric wire 310 is electrically connected to the press-contact blade 332 as follows. That is, the covered electric wire 310 is guided along the guide part 335 and press-fitted into the slot 333. Then, the insulative cover 313 is cut out by a slightly sharp part 333A of the upper end of the slot 333 to expose the core wire 311. The exposed core wire 311 is pushed further into the slot 333 while contacting with both slot-edges 334 of the slot 333 and electrically connects to the press-contact blade 332.

Citation List

Patent Literature

Patent Literature l: JP A-2010-33776

Summary of Invention

Technical Problem

The press-contact blade 332 has a following problem. That is, since the sharp parts 333A which cut out the insulative cover 313 of the covered electric wire 310 are provided in pair in opposite positions, when the covered electric wire 310 is to be press-fitted into the slot 333 of the press-contact blade 332, a load of cutting out the insulative cover 313, a load of sliding the both slot-edges 334 of the slot 333 on the core wire 311 and a load of pressing the core wire 311 by the both slot-edges 334 of the slot 333 are applied at the same time. Accordingly, a press-contact load becomes large at the same time and point.

An object of the invention is therefore to provide a press-contact blade capable of reducing a press-contact load to be applied when a covered electric wire is press-fitted into a slot of the press-contact blade.

Solution to Problem

In order to achieve the object, according to a first aspect of the present invention, there is provided a press-contact blade, including: a slot for press-fitting therein a covered electric wire in which a core wire is covered with an insulative cover to cut out the insulative cover and cause the press-contact blade to contact the core wire; a pair of slot-edge parts that defines the slot therebetween; one slot-edge part of the pair of slot-edge parts including a first cut-out part located at a leading edge of the press-contact blade to be sharply formed to cut out the insulative cover and a first straight part located at a deeper side of the slot than the first cut-out part; and the other slot-edge part of the pair of slot-edge parts including a wire-pressing part that faces the first cut-out part, a second cut-out part located at a deeper side of the slot than the wire-pressing part to be sharply formed to cut out the insulative cover and facing the first straight part, and a second straight part located at a deeper side of the slot than the second cut-out part and facing the first straight part, wherein the second cut-out part protrudes toward the one slot-edge part more than the wire-pressing part does.

The press-contact blade may be configured in a second aspect so that the wire-pressing part extends from an edge of the other slot-edge part that faces the slot in a plate-shape, and the wire-pressing part contacts an outer surface of the covered electric wire when the insulative cover of the covered electric wire is cut out by the first cut-out part. The press-contact blade may be configured in a third aspect so that a dimension of a clearance between the first straight part and the second straight part is equal to a dimension of a clearance between the first straight part and the second cut out part.

The press-contact blade may be configured in a fourth aspect so that a notch is provided between the wire-pressing part and the second cut-out part.

Advantageous Effects of Invention

According to the first aspect of the present invention, one slot-edge part of the pair of slot-edge parts includes a first cut-out part located at a leading edge of the press-contact blade to be sharply formed to cut out the insulative cover and a first straight part located at a deeper side of the slot than the first cut-out part, and the other slot-edge part of the pair of slot-edge parts includes a wire-pressing part that faces the first cut-out part, a second cut-out part located at a deeper side of the slot than the

wire-pressing part to be sharply formed to cut out the insulative cover and facing the first straight part, and a second straight part located at a deeper side of the slot than the second cut-out part and facing the first straight part. Further, the second cut-out part protrudes toward the one slot-edge part more than the wire-pressing part does. Accordingly, a timing at which the first cut-out part cuts out the one side of the insulative cover is different from a timing at which the second cut-out part cuts out the opposite side of the insulative cover. In this way, there is provided a press-contact blade capable of reducing the press-contact load to be applied when the covered electric wire is press-fitted into the slot of the press-contact blade.

According to the second aspect, the wire-pressing part extends from an edge of the other slot-edge part that faces the slot in a plate-shape, and the wire-pressing part contacts an outer surface of the covered electric wire when the insulative cover of the covered electric wire is cut out by the first cut-out part. Accordingly, a part of the covered electric wire corresponding to the wire-pressing part is prevented from being cut out, and it is possible that the timing at which the first cut-out part cuts out the one side of the insulative cover is surely different from the timing at which the second cut out part cuts out the opposite side of the insulative cover.

According to the third aspect, the dimension of the clearance between the first straight part and the second straight part is equal to the dimension of the clearance between the first straight part and the second cut-out part. Accordingly, it is possible to prevent a press-pressure of the first straight part and the second straight part from being lowered with respect to the core wire when the covered electric wire in which the insulative cover is cut-out by the second cut-out part is moved further to the deeper side of the slot.

According to the fourth aspect/the notch is provided between the wire-pressing part and the second cut-out part. Accordingly, the second cut-out part cuts in the covered electric wire more deeply rather than in a case where the notch is excluded. Thus, the insulative cover can be cut-out by the second cut-out part surely.

Brief Description of Drawings

Fig. 1 is a perspective view showing a press-contact blade according to an embodiment of the invention.

Fig. 2 is a perspective view showing an in -vehicle room lamp which includes a bus bar provided with the press-contact blade shown in Fig. 1.

Fig. 3 is a perspective view showing a state in which a wire holder of the in-vehicle room lamp shown in Fig. 2 is separated from a housing.

Fig. 4 is an exploded view of the in-vehicle room lamp shown in Fig.

3.

Fig. 5 is a cross -sectional view taken along a line V-V in Fig. 2.

Fig. 6 is a cross -sectional view taken along a line VTVI in Fig. 3. Figs. 7A, 7B, 7C, 7D and 7E are diagrams for describing that the press-contact blade shown in Fig. 1 press-contacts a covered electric wire, in which Fig. 7A shows a state before the covered electric wire is press-fitted into a slot of the press-contact blade, Fig. 7B shows a state in which the covered electric wire starts to be press-fitted into the slot of the press-contact blade and a first cut-out part cuts an insulative cover, Fig. 7C shows a state in which the covered electric wire shown in Fig. 7B is further moved into the slot to be positioned between a first straight part and a wire-pressing part, Fig. 7D shows a state in which the covered electric wire shown in Fig. 7C is further moved into the slot and a second cut-out part cuts the insulative cover, and Fig. 7E shows a state in which the covered electric wire shown in Fig. 7D is further moved into the slot to be positioned between the first straight part and a second straight part.

Fig. 8 is a cross-sectional view showing a state in which a

press-contact blade in a related art press-contacts with a covered electric wire. Fig. 9 is a cross -sectional view showing a state before the covered electric wire shown in Fig. 8 is press-fitted into a slot of the press-contact blade. Description of Embodiments

Description is made of a press-contact blade according to an

embodiment of the invention with reference to Figs. 1 to 7E.

A press-contact blade 1 according to the embodiment as shown in Fig. 1 is provided in each of bus bars 2A, 2B, 2C shown in Figs. 2 to 6. The bus bars 2A, 2B, 2C are used as a wiring member in an in-vehicle room lamp 100 shown in Fig. 2. Each of the bus bars 2A, 2B, 2C is obtained by, for example, press-working a metal plate.

The press-contact blade 1 is electrically connected to a covered electric wire 10. The covered electric wire 10 is a circular cross-sectional electric wire in which a conductive core wire 11 is covered with an insulative cover 12 (refer to Fig. 7A). As shown in Fig. 1, a slot 13 into which the covered electric wire 10 can be press-fitted is provided in a center part in a width direction of the press-contact blade 1 to open at a leading edge of the press-contact blade 1. In the embodiment, a pair of edge parts that defines the slot 13 therebetween in the press-contact blade 1 is referred to as slot-edge parts 13A, 13B.

One slot-edge part 13A of the pair of slot-edge parts 13A, 13B includes a first cut-out part 14 located at a leading edge of the press-contact blade 1 to be sharply formed to cut out the insulative cover 12, and a first straight part 15 located at a deeper side of the slot 13 than the first cut-out part 14. The deep side of the slot 13 means a side separate away from an opening part of the slot 13 in its longitudinal direction, or an entrance of the covered electric wire 10.

The first cut-out part 14 is inclined toward a wire-pressing part 16 from the entrance to the deep side of the slot 13. A dimension of a clearance between the first cut-out part 14 and the wire-pressing part 16 is smaller than the diameter of the covered electric wire 10. In this embodiment, the dimension of the clearance between the first cut-out part 14 and the wire-pressing part 16 is defined as a dimension of a clearance between an end of the first cut out part 14 at the deeper side of the slot 13 and the wire-pressing part 16.

The first straight part 15 extends along a straight line from the end of the first cut-out part 14 at a deeper side of the slot 13 to the deepest end of the slot 13. The first straight part 15 also extends along a straight line in a direction orthogonal to a width direction of the press-contact blade 1.

The other slot-edge part 13B of the pair of slot-edge parts 13A, 13B includes the wire-pressing part 16 that faces the first cut-out part 14, a second cut-out part 17 located at a deeper side of the slot 13 than the wire-pressing part to be sharply formed to cut out the insulative cover 12, a second straight part 18 located at a deeper side of the slot 13 than the second cut-out part 17, and a notch 19 that is notched between the wire-pressing part 16 and the second cut-out part 17.

The wire-pressing part 16 extends from an edge of the other slot-edge part 13B that faces the slot 13 in a plate-shape. The wire-pressing part 16 extends in an orthogonal direction to the width direction and the longitudinal direction of the press-contact blade 1. The wire-pressing part 16 is formed by folding a single metallic plate substantially at a right angle. The wire-pressing part 16 provided in this way contacts an outer surface of the covered electric wire 10 when the covered electric wire 10 passes between the first cut-out part 14 and the wire-pressing part 16. Then, the first cut-out part 14 cuts in the insulative cover 12 of the covered electric wire 10 and cuts out one side of the insulative cover 12.

In this way, since the wire-pressing part 16 in this embodiment surface-contacts the outer surface of the covered electric wire 10, a part of the covered electric wire 10 corresponding to the wire-pressing part 16 is prevented from being cut out.

The second cut-out part 17 is inclined toward the first straight part 15 from the entrance to the deep side of the slot 13. One end of the second cut-out part 17 at an entrance-side of the slot 13 is located more separately away from the one slot-edge part 13A than the wire-pressing part 16. The other end of the second cut-out part 17 at a deep-side of the slot 13 is located closer to the one slot-edge part 13A than the wire-pressing part 16. That is, the second cut-out part 17 protrudes toward the one slot-edge part 13Amore than the wire-pressing part 16 does. The second cut out part 17 provided in this way cuts in the insulative cover 12 of the covered electric wire 10 and cuts out the other side of the insulative cover 12, i.e., a part opposite to the part that is cut-out by the first cut out part 14 when the covered electric wire 10 passes between the first straight part 15 and the second cut-out part 17.

The notch 19 is open in the slot 13, and notched in the width direction of the press-contact blade 1 between the wire-pressing part 16 and the second cut-out part 17.

In this embodiment, since the notch 19 is provided in this way, the second cut-out part 17 cuts in the covered electric wire 10 more deeply rather than in a case where the notch 19 is excluded. Thus, the insulative cover 12 can be cut out by the second cut out part 17 surely. However, the notch 19 is not necessarily provided.

The second straight part 18 extends along a straight line from the end of the second cut-out part 17 at the deeper side of the slot 13 to the deepest end of the slot 13. The second straight part 18 extends in parallel to the first straight part 15.

A dimension Kl of a clearance between the first straight part 15 and the second straight part 18 is equal to a dimension K2 of a clearance between the first straight part 15 and the second cut-out part 17. In this

embodiment, the dimension K2 of the clearance between the first straight part 15 and the second cut-out part 17 is defined as a dimension of a clearance between the first straight part and the end of the second cut-out part 17 at the deeper side of the slot 13. The first straight part 15 and the second straight part 18 provided in this way contact with the core wire 11 which is exposed by cutting out the insulative cover 12 by the first cut out part 14 and the second cut-out part 17, thereby to hold the core wire 11 between the first straight part 15 and the second straight part 18.

In this embodiment, since the dimension Kl of the clearance between the first straight part 15 and the second straight part 18 is equal to the dimension K2 of the clearance between the first straight part 15 and the second cut-out part 17, it is possible to prevent a press-pressure of the first straight part 15 and the second straight part 18 from being lowered with respect to the core wire 11 when the covered electric wire 10 in which the insulative cover 12 is cut-out by the second cut-out part 17 is moved further to the deeper side of the slot 13.

The covered electric wire 10 is electrically connected to the

press-contact blade 1 as explained below. Fig. 7A shows a state before the covered electric wire 10 is press-fitted into the slot 13 of the press-contact blade 1. As shown in Fig. 7B, when the covered electric wire 10 is

press-fitted into the entrance of the slot 13, the one side of the insulative cover 12 is cut out by the first cut-out part 14, and also the opposite side of the insulative cover 12 contacts with the wire-pressing part 16. At this time, the part of the insulative cover 12 that contacts with the wire-pressing part 16 is not cut out yet. Then, when the covered electric wire 10 is further pressed to the deeper side of the slot 13, as shown in Fig. 7C, the core wire 11 that is exposed by cutting out the insulative cover 12 by the first cut-out part 14 contacts with the first straight part 15. Then, when the covered electric wire 10 is further pressed to the deeper side of the slot 13, as shown in Fig. 7D, the opposite side of the insulative cover 12, i.e., the part of the insulative cover 12 opposite to the part that is cut out by the first cut-out part 14 is cut out by the second cut-out part 17. Then, when the covered electric wire 10 is further pressed to the deeper side of the slot 13, as shown in Fig. 7E, the core wire 11 that is exposed by cutting out the insulative cover 12 by the second cut-out part 17 contacts with the second straight part 18, and the core wire 11 is held between the first straight part 15 and the second straight part 18. In this way, the core wire 11 contacts the first straight part 15 and the second straight part 18, thereby electrically connecting the covered electric wire 10 to the press-contact blade 1.

In this way, the press-contact blade 1 in this embodiment can reduce a press-contact load to be applied when the covered electric wire 10 is press-fitted into the slot 13 since it is configured that a timing at which the first cut-out part 14 cuts out the one side of the insulative cover 12 is different from a timing at which the second cut out part 17 cuts out the opposite side of the insulative cover 12.

Next, a description is made of the in-vehicle room lamp 100. The in-vehicle room lamp 100 includes, as shown in Figs. 2 to 4, a housing 3 which is made of synthetic resin, a bulb 6 which is attached to the housing 3, a lens 4 which is attached to the housing 3 and covers the bulb 6, a metal chp 7 for fixing the housing 3 to a vehicle body, a wire holder 9 which is inserted into a holder-attaching part 32 provided in the housing 3 while holding the three covered electric wires 10 and supplies power to the bulb 6 from a power supply, the plurality of bus bars 2A, 2B, 2C which connect the bulb 6 to the covered electric wires 10 held by the wire holder 9, a switch body 8 which is connected to the bus bars 2A, 2B, 2C and controls turning-on and turning-off of the bulb 6, and a switching knob 5 as a manipulation part of the switch body 8.

The plurality of bus bars 2A, 2B, 2C include attaching holes through which pins 31 provided in the housing 3 is passed, a bulb-holding part 20 which holds an electrode of the bulb 6, and the press-contact blades 1 which are located in the holder-attaching part 32 and connected to the covered electric wires 10 held by the wire holder 9. The plurality of bus bars 2 A, 2B, 2C are attached to the housing 3 by thermally welding the pins 31 which are passed through the attaching holes.

As shown in Figs. 5 and 6, the wire holder 9 is formed in a

square-block, and inserted into the holder- attaching part 32 while holding the three covered electric wires, thereby being attached to the housing 3. By actions of inserting the wire holder 9 into the holder-attaching part 32, each covered electric wire 10 is electrically connected to the respective one of the press-contact blades 1 which is provided in each of the plurality of bus bars 2A, 2B, 2C.

The three covered electric wires 10 are connected to the respective contact blades 1 concurrently at the same timing. However, the

press-contact blade 1 in this embodiment can reduce an insertion force to be applied when the wire holder 9 is inserted into the holder- attaching part 32 since it is configured that the press-contact load when the covered electric wire 10 is press-fitted into the slot 13 is reduced as explained above.

Further, the in-vehicle room lamp 100 can reduce the assembling cost since it is configured that the covered electric wires 10 are electrically connected to the respective press-contact blades 1 by using the wire holder 9 and the holder- attaching part 32 without using a press-contact machine. Further, since the press-contact machine is not required, the covered electric wires 10 are electrically connected to the respective press-contact blades 1 in any desired step in the assembling procedure without limiting the space of work.

In this embodiment, although an example is explained of the press-contact blades 1 are provided in the bus bars 2A, 2B, 2C, the press-contact blade may be provided in a terminal fitting that constitutes a connector or the like instead of providing it in the bus bars 2A, 2B, 2C.

The embodiment as explained above is a representative mode of the present invention, but the present invention is not limited to the

embodiment as explained above. That is, it can be deformed in various ways without departing from a gist of the present invention.

This application is based on and claims the benefit of Japanese patent application No. 2011-57613 filed on March 16, 2011, the contents of which are incorporated herein in its entirety by reference.

Reference Signs List

1- press-contact blade

10 ^'■ covered electric wire

11 · core wire

12: insulative cover

13: slot

13A, 13B: slot-edge part

14: first cut-out part

15: first straight part

16: wire-pressing part

17: second cut-out part

18: second straight part

19: notch

Claims

1. A press-contact blade, comprising:

a slot for press-fitting therein a covered electric wire in which a core wire is covered with an insulative cover to cut out the insulative cover and cause the press-contact blade to contact the core wire;

a pair of slot-edge parts that defines the slot therebetween; one slot-edge part of the pair of slot-edge parts including a first cut-out part located at a leading edge of the press-contact blade to be sharply formed to cut out the insulative cover and a first straight part located at a deeper side of the slot than the first cut-out part; and

the other slot-edge part of the pair of slot-edge parts including a wire-pressing part that faces the first cut out part, a second cut-out part located at a deeper side of the slot than the wire-pressing part to be sharply formed to cut out the insulative cover and facing the first straight part, and a second straight part located at a deeper side of the slot than the second cut out part and facing the first straight part, wherein

the second cut-out part protrudes toward the one slot-edge part more than the wire-pressing part does.

2. The press-contact blade according to claim 1, wherein

the wire-pressing part extends from an edge of the other slot-edge part that faces the slot in a plate-shape, and the wire-pressing part contacts an outer surface of the covered electric wire when the insulative cover of the covered electric wire is cut out by the first cut-out part.

3. The press-contact blade according to claim 1 or 2, wherein

a dimension of a clearance between the first straight part and the second straight part is equal to a dimension of a clearance between the first straight part and the second cut-out part.

4. The press-contact blade according to any one of claims 1 to 3, wherein a notch is provided between the wire-pressing part and the second cut-out part.