JPH053716B2 - - Google Patents

Abstract

Edge connector for a printed circuit board (35) comprises a housing (1) having terminals (21) therein. Terminals have spaced apart spring arms (26) which contact opposite surfaces of the circuit board (35). The terminals (2) are in a first position when the circuit board (35) is inserted into the housing (1) such that the spring arms (26) are spaced apart and the circuit board can be readily inserted. After initial insertion, the circuit board (35) and terminals (21) are moved relative to the housing (1) and camming surfaces in the housing (1) cam the arms (26) towards each other and against the circuit board (35).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to edge connectors for printed circuit boards, ceramic substrates, etc., and in particular to the problem of providing so-called low insertion force (LIF) or zero insertion force (ZIF) functionality in this type of connector. It is related to.

The LIF or ZIF function is desirable in multi-wire connectors in order to reduce engagement and disengagement forces between mating connectors. Connectors are known in which the contact pieces can be engaged or disengaged in a disengaged state and there is no frictional engagement on the contact surfaces during engagement of the connector housing. Engagement of the contact pieces is then effected, for example, by relative movement of the contacts by means of a cam member movable on the connector housing.

Avoiding frictional engagement between the edge connector contact strips and the printed circuit board or substrate is important if the edges of the circuit board or substrate are sharp due to the manufacturing process and could severely damage the contact surfaces. This is especially important because there are For example, when a ceramic substrate or the like is cut to size with a laser, sharp edges are created at the cut portion.

It is an object of the present invention to enable the contact surface to engage the edge of the circuit board or board after insertion without having to engage the edge of the circuit board or board from the beginning, and to provide an additional member to the housing or the contact piece. To provide an edge connector that can be economically produced without the need for an edge connector.

The edge connector of the present invention has a plurality of through cavities, and a housing in which a slot for receiving one end edge of the board is formed in the axial direction from one end in each through cavity, and a housing disposed in the through cavity and provided on both sides of the board. In the edge connector, each of the through cavities is formed with a narrow part and a wide part on both sides of the slot, and the contact piece has a tapered part on the one end side. A pair of spring arms are provided, and a portion for receiving the one end edge of the substrate is provided between the spring arms, the other end being connectable to a wire, and a contact portion for contacting the substrate at the free end of each spring arm. The through-hole cavity and the contact piece are provided with two engaging portions spaced apart in the axial direction that engage with each other to restrict movement in the axial direction, and the contact piece is provided with the substrate into which the substrate is inserted. Then, the spring arm moves inward between the engaging portions, and the pair of spring arms is bent inward by the narrower inner width portion of the through cavity and comes into contact with the substrate.

The contact piece has an extension located between the spring arms that protrudes into the slot in the first state, the protruding extension aligning with the edge of the circuit board or board upon engagement with the circuit board or board of the connector. Preferably, the contact piece is moved to the rear of the slot to move the contact piece to the second state.

Preferably, the projecting extension is formed with a spring extension which engages a slope formed in one wall of the cavity to bias the contact piece towards the first condition.

Movement of the contact piece between the first and second states is suitably limited by stops formed in the cavity.

The contact piece is formed with a plurality of flared spring arms, and the cavity has a width that decreases behind the slot so that the spring arms engage the reduced width portion of the cavity as the contact piece moves between the first and second states. They are restrained by the contact surfaces and approach each other, allowing their contact surfaces to enter the slot.

The present invention also includes a contact piece for a connector of the present invention that includes a channel-shaped body and opposite walls of the groove extend from one end to form a pair of spring arms with opposing contact surfaces. It is characterized in that an extension is formed at the bottom of the grooved body and projects forward between the spring arms to a position rearward of the contact surface.

Preferably, this extension of the groove bottom is appropriately folded back diagonally to form a spring arm whose free end is spaced from the bottom surface between the two side walls of the groove-shaped portion.

Preferably, the spring arm with the contact surface extends out from the groove in a flared manner.

The invention will now be described by way of example with reference to the partially schematic drawings, in which: FIG.

The connector housing shown in FIGS. 1 to 5 is integrally molded from an elastic plastic insulating material, and includes a connector body 1 having an overall rectangular flat plate shape and having one principal surface, and a mounting portion 2. The main body 1 is formed with a row of five through cavities 3, and a slot 4 which traverses the cavities 3 at the lower end as seen in FIG. 2 and penetrates between opposite ends of the main body 1. The inner width of the through cavity 3 is relatively large at one end of the housing, as shown in FIG. 2, and gradually decreases as it moves upward in the drawing through a pair of sloped surfaces 39. A flap 5 is provided at the upper end of the surface opposite to the mounting portion 2, passing over all the cavities 3 and reaching from one end of the main body 1 to the other end. The flap 5 is integrally connected to the main body 1 by a hinge 6 at the center between the upper and lower ends of the main body 1. The upper edge of the flap 5 is provided with a series of latch projections 7, each having a latch hole 8 and projecting laterally onto the partition wall 9 between the cavities 3.

A projection 10 formed on the partition wall 9 engages in the hole 8 to fix the flap 5 in the position shown.

The flap 5, with the latch projection 7 removed from the wall projection 10, can be pivoted counterclockwise from the position shown by 90 degrees by bending at the hinge 6 between the open position and the closed position shown. .

On the side of the cavity 3 of the flap 5 near the hinge 6, a series of inwardly projecting steps 11 are provided, one for each cavity 3, which act as a stop, and are provided with a contact piece, which will be described later with reference to FIGS. 7 to 10. It has a downward step surface for holding.

Each cavity 3 has upper and lower sloped surfaces 13, 1, which are cam-engaged with a part of one contact piece, as will be described later, at approximately the height of the hinge 6 on one of the side walls straddling the slot 4.
An inner protrusion 12 with 4 is provided. A shallow groove 15 rising higher than the slot 4 from the mouth of the slot 4 is provided on the opposite side wall of each cavity, and the upper end thereof has a downwardly facing step surface 16 (an engaging surface) which acts as a stopper for holding the contact piece, which will be described later. It ends with (part). These side walls of each cavity are also formed with upwardly facing stepped surfaces 17 (engaging portions) that act as stoppers and are located slightly above the height of the slot 4 adjacent to the other two side walls to control the degree of insertion of the contact piece. Restrict. These two side walls widen downward below the stepped surface 17 to define an enlarged lower cavity portion surrounding the slot 4, as shown in FIG.

The mounting part 2 is a bridge part 19 separated from the main body 1.
It has a pair of spaced apart arms 18 depending from the base (FIG. 1). These arms 18, as shown in FIGS. 1 and 4, are groove-shaped and open outward.
The lower end of the groove is closed with a latch portion 20 having both upper and lower slopes. The arms allow the connector to be releasably secured to the fixture by resiliently deflecting the lower ends inward to allow the latch portion 20 to be attached to and removed from mating means of the fixture.

The contact piece of FIGS. 5 and 6 includes a channel portion 21 having a wire contacting portion 22 at one end, which wire connecting portion 22 is of conventional shape and is continuous with a U-shaped wire crimp ferrule 23 and a carrier strip 25. and an insulating support ferrule 24. Channel part 2
At the other end of 1, opposite side walls of the groove support spring arms 26.
The free ends thereof are curved inward in an arc shape to form opposing arc-shaped contact portions 27. As seen in the side elevation view of FIG. 5, both spring arms 26 taper in width toward their free ends.

An extension part 28 is formed between both arms 26 at the bottom of the groove-shaped part 21, and as shown in FIG. has been done. The extension 28 further extends rearwardly and upwardly between the arms 26 to form a folded extension 30 at a portion 37, the free end 31 of which projects from the channel portion 21 (FIG. 5). The free end 31 is curved downward and presents a convexly curved engagement surface upward.

The bottom of the channel portion 21 is also provided with a retaining latch 32 (engaging portion) which is pushed out from the rear opening of the embossing 29 and extends downwardly and rearwardly.

In operation, the contact strips of FIGS. 5 and 6 are cut from the carrier strip 25 and crimped onto the stripped wire ends 33 in the conventional manner to form the contact strips of FIGS. A terminated lead is made to be assembled into the connector housing shown in FIGS. The mounting part 2 of the connector housing is not shown in FIGS. 7 and 9. To install the terminated leads into the connector housing, move the flap 5 to the open position and remove the shoulder 11.
Take it out of cavity 3. The contact piece is inserted into each cavity 3, and the front end of the contact spring 26 first engages the two opposite side walls of the cavity 3 below the hinge 6, is deflected inward and enters the cavity, and the retaining latch 32 enters the groove 15 and engages with the stepped surface 16 to prevent the contact piece from coming out of the housing. During insertion, the free ends 31 of the extensions 28, 30 abut the ramps 13 causing the extensions 30 to deflect inwardly into engagement with the ramps 14. This state corresponds to FIGS. 9 and 10, but with the spring arm 2
6 is restrained inwardly by the cavity wall, and stepped surfaces 34 (engaging portions) at the lower ends of the groove-shaped portions 21 on both sides of the extension are spaced upward from the stepped surfaces 17 of the housing. This contact piece can therefore move further down into the cavity 3 and the extension 30 resting against the slope 14
The deflection exerts a downward force on the contact piece, causing it to descend until the stepped surfaces 34, 17 engage to prevent further descent. At this time, the contact piece assumes the state shown in FIGS. 7 and 8.

In this state, both spring arms 26 have entered the widened lower part of the cavity and are spread out on both sides of the slot 4, with the contact ends 27 being on the outside of the slot 4. The distal or lower end (portion 37) of the extension 28 is located within the slot 4 and engages the retaining latch 32.
is spaced downward from the stepped surface 16.

When all the contact pieces have been assembled into their respective cavities 3 and the flap 5 is closed in the state shown in FIGS.
The latch 32 enters the respective cavity at the upper rear and is aligned with the rear or upper edge of the channel portion 21 as shown in FIGS. Hold the contact piece.

In the connector in the state shown in FIGS. 7 and 8, the edge of the board 35 is connected to the lower front end (portion 3
7), it can be assembled to the board 35 by entering the slot 4 from between the contact portions 27 until it hits point 7). In the position shown in FIG. 7, the contact portion 27 is out of the slot and is not engaged with the substrate 35, so there is no risk of damage to the contact surface due to wear caused by the sharp edges of the substrate 35. Board 35
As the contact piece advances further into the slot 4, the contact piece is pushed upwards or backwards within the cavity 3;
The extension 30 is deflected inwardly by the ramp 14;
The pair of spring arms 26 are deflected inwardly by the through cavity 3 whose inner width gradually decreases through a pair of sloped surfaces 39. In this way, the contact ends 27 are pressed against both sides of the substrate to exert a contact force, as shown in FIG.

The base plate 35 is suitably supported on a fixture having means complementary to the latch arm 18 of the mounting part 2 of the connector, the latch arm 18 having its free end 20
The connector is then snapped into the complementary means to fix the connector in the state shown in FIGS. 9 and 10. To release the connector, flex the latch arms 18 inwardly toward each other and raise the housing from the position of FIG. 9 to the positions of FIGS. 7 and 8 to release the connector onto the board.
Just take it out from 5. The engagement of the spring extension 30 with the slope of its free end 31 causes the contact piece to be pressed down relative to the housing so that the contact portion 27
is separated from the board before the connector is pulled out from the board 35, resulting in the state shown in FIG. Therefore, friction between the contact portion 27 and the substrate 35 and engagement with a sharp edge can be avoided.

As explained above, in the present invention, a small portion and a large portion of the inner width of the through cavity are formed on both sides of the slot of the through cavity, and the contact piece connected to the electric wire has a pair of contact portions at the free ends. A spring arm is provided with a portion for receiving one end edge of the substrate between the spring arms, and the through cavity and the contact piece are provided with two engaging portions spaced apart in the axial direction so that the contact piece can move within a predetermined range in the axial direction; When the board is inserted, the contact piece moves inward within the through cavity, causing the spring arm to flex inward and come into contact with the board, resulting in the following effects.

Zero or low insertion force can be obtained by simply moving the contact piece itself, which comes into contact with the electric wire, within the housing within a predetermined range in the axial direction, and no additional members are required. Therefore, an edge connector with a simple structure and low cost can be obtained. By changing the shape of the spring arm and the inner width of the through cavity, it is possible to easily accommodate various substrate thicknesses, and also to easily obtain a desired contact pressure due to the elasticity of the spring arm.

[Brief explanation of the drawing]

Fig. 1 is an elevational view of one side of the connector housing, Fig. 2 is a sectional view taken along line 2-2 in Fig. 1, and Fig. 3 is a cross-sectional view of one end cavity of the connector shown in Fig. 1, viewed from the opposite side. Elevation view, FIG. 4 is a plan view of the connector shown in FIG. 1, FIG. 5 is an enlarged elevational view of the contact piece used in the connector shown in FIGS. 1 to 4, and FIG. 6 is the contact piece shown in FIG. 5. 7 is a cross-sectional view of one cavity of the connector that accommodates the contact pieces of FIGS. 5 and 6 and is in the initial state of engagement with the board, viewed from the opposite direction from FIG. 8 is a sectional view taken along the line 8-8 of FIG. 7 in the direction of the arrow; FIG. 9 is a view similar to FIG. 7, with the board fully engaged with the connector; and FIG. 10.
The figure is a view similar to FIG. 8, with the contact piece in the same state as FIG. 9. 1...Insulating housing, 3...Through cavity, 4...Slot, 16, 17, 32, 34...
...Engaging part, 26... Spring arm, 27... Contact part, 33... Wire end, 35... Board, 37...
Part 39... slope.

Claims (1)

[Scope of Claims] 1. A housing having a plurality of through cavities, each of which has a slot formed in the axial direction from one end for receiving one end edge of the substrate, and a housing disposed within the through cavity and both sides of the substrate. In the edge connector, each of the through cavities has a narrow portion and a wide portion on both sides of the slot, and each of the through cavities has a narrow portion and a wide portion on both sides of the slot, and each of the through cavities has a narrow portion and a wide portion on the one end side. A pair of spring arms are provided, and a portion for receiving the one end edge of the substrate is provided between the spring arms, the other end being connectable to a wire, and a contact portion for contacting the substrate at the free end of each spring arm. The through-hole cavity and the contact piece are provided with two engaging portions spaced apart in the axial direction that engage with each other to restrict movement in the axial direction, and the contact piece is provided with the substrate into which the substrate is inserted. The edge connector is characterized in that the pair of spring arms is moved inwardly between the engaging portions, and the pair of spring arms is bent inward by a narrower inner width portion of the through cavity and comes into contact with the substrate.