JPH11160724A - Mounting structure for liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of solder crack at the soldering part of the electrode lead and circuit board of a liquid crystal display element even when a stress distortion is generated by thermal expansion. SOLUTION: A casing 3 is provided with a placing part 6 for arranging a liquid crystal display element 1. Electrode leads 2 are arranged in the form of column on the liquid crystal display element 1 and arranged in the state of being abutted to at least a part of the casing 3 when the liquid crystal display element 1 is arranged at the placing part 6. A circuit board 4 forms an inserting hole 11 for inserting the electrode lead 2 and arranges the casing 3 while being electrically connected with the electrode leads 2. A through hole (first positioning part) 13 is passed through the front side and rear side of the circuit board. A boss (second positioning part) 9 is provided on the casing 3, determined the position of the casing 3 in respect to the circuit board 4 and is engaged with the through hole 13. The guide parts 2e are formed at each top end part of the electrode leads 2 and guide the electrode leads 2 into the inserting holes 11. The bent parts 2c are formed more backward than the guide parts 2e and change the electrode leads 2 into state away from a state abutting to the casing 3 when the bossing 9 is engaged with the through hole 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a liquid crystal display element having a plurality of electrode leads in rows on a circuit board.

[0002]

2. Description of the Related Art A conventional mounting structure of a liquid crystal display element is disclosed in Japanese Utility Model Laid-Open No. 4-65484. The mounting structure of this type of liquid crystal display element has a case in which a transmission type liquid crystal display element having electrode leads arranged in a row on one side, and the electrode leads being lead-formed in a substantially vertical direction from a liquid crystal display portion, is provided. The electrode lead of the liquid crystal display element is disposed at an upper end portion, and the electrode leads are disposed so as to correspond to partitions, such as a plurality of grooves or insertion holes, which are disposed at a distance from each other, and are formed on a circuit board. After the electrode lead is inserted into the hole, the electrode lead and the circuit board are fixed by soldering. Further, the liquid crystal display element has a structure which is inserted from the back surface side of the circuit board corresponding to a place where the case is provided, and is electrically connected to the circuit board, for example, transmitted and illuminated by a lighting bulb. is there.

[0003] In the mounting structure of the liquid crystal display element on the circuit board, when the electrode leads are provided in the insertion holes of the circuit board, the electrode leads are provided in a row and the electrode leads are provided in a row. However, there is a problem that it is difficult to set in the insertion hole unless a dedicated jig is used, since it is easily deformed. In consideration of this problem, the electrode lead is formed so that the forming angle of the electrode lead is inward of the vertical direction (vertical direction) as compared with the related art in which the electrode lead is formed so as to be substantially vertical from the liquid crystal display unit. When the liquid crystal display element is disposed at the upper end of the case, the electrode lead is brought into contact with the partition portion, so that the case is formed on the case. Positioning arrangement, in this state, the electrode lead is inserted through the insertion hole of the circuit board,
After arranging the case on the circuit board, a structure is adopted in which the electrode leads protruding from the back side of the circuit board are electrically fixed to connection lands formed on the circuit board by soldering.

[0004]

For example, when a liquid crystal display device having the above-described mounting structure is used as a display device for a vehicle, if the ambient temperature changes due to various use environments,
Due to a difference in thermal expansion coefficient between the circuit board and the case, stress distortion occurs between both members. In the above-described mounting structure of the liquid crystal display element, since the electrode leads are disposed in a state of being in contact with the case (partition portion) even after being soldered to the circuit board, the stress of the electrode leads is reduced. The amount of displacement due to strain is greater than when the electrode leads are disposed free from the circuit board because the electrode leads fluctuate with the case, and the amount of soldering between the electrode leads and the circuit board is larger. There was a risk that solder cracks would occur at the attachment part.

Therefore, the present invention focuses on the above problem, and a liquid crystal which does not generate solder cracks in a soldered portion between an electrode lead of a liquid crystal display element and a circuit board even when stress distortion occurs due to thermal expansion. It is intended to provide a mounting structure of a display element.

[0006]

In order to solve the above-mentioned problems, the present invention provides a liquid crystal display element, a case body having a mounting portion for disposing the liquid crystal display element, and a liquid crystal display element. And an insertion hole for inserting the electrode lead, the electrode lead being disposed in a state of contacting at least a part of the case body when the liquid crystal display element is disposed in the mounting portion. And a circuit board that is electrically connected to the electrode leads, and on which the case body is provided,
A first positioning portion provided on the circuit board; and a second positioning portion provided on the case body, for determining a position of the case body with respect to the circuit board, and engaging with the first positioning portion. A guide portion formed at the tip of the electrode lead, for guiding the electrode lead into the insertion hole;
And a bent portion formed behind the guide portion and transitioning from a state in which the electrode lead is in contact with the case body to a state in which the electrode lead is separated when the positioning portions are engaged. is there.

Further, the case body is provided with a partition for disposing the electrode leads at a distance from each other.

The first positioning portion may be a through hole penetrating the front and back of the circuit board, and the second positioning portion may be a boss extending from the case body. The boss body is engaged.

Further, first and second locking portions are formed on the case body and the circuit board, and the locking portions are engaged with each other.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a mounting structure for mounting a liquid crystal display element 1 on a circuit board 4. A guide portion formed on the electrode lead 2 (2 ′) while the electrode lead 2 (2 ′) is in contact with a groove (partition portion) 7 (7 ′) formed on the case body 3 and held by the case body 3. 2e
(2e ') is disposed in the insertion hole 11 (11') of the circuit board 4, and the boss body (second positioning portion) 9 provided in the case body 3
Is inserted (engaged) into the through hole (first positioning portion) 16 of the circuit board 4, the guide portion 2 e (2 e ′) formed on the electrode lead 2 (2 ′) and the inclined portion 2 d (2 d ′). ), The bent portion 2c (2c ') of the electrode lead 2 (2') is disposed in the insertion hole 11 (11 '), so that the electrode lead 2 (2') is removed from the case body 3. It is possible to hold on the circuit board 4 in a state of being separated. Therefore, since the electrode leads 2 (2 ′) can be arranged and fixed on the circuit board 4 in a state where the electrode leads 2 (2 ′) are not brought into contact with the case body 3, the ambient temperature changes and the thermal expansion coefficient between the case body 3 and the circuit board 4 varies. Even when stress distortion occurs, the electrode lead 2 (2 ') does not fluctuate with the case body 3, so that the land portion 12 (12') of the circuit board 4 and the electrode lead 2 (2 ') do not move. Since the stress distortion at the soldered portion can be suppressed as compared with the conventional structure, the occurrence of solder cracks can be eliminated.

Further, a through hole 13 penetrating the front and back of the circuit board 4 and a boss body 9 extending from the case body 3 are provided, and the electrode lead 2 (2 ') is formed simply by engaging the above-mentioned parts. Can be shifted from the state in which the electrode lead 2 is in contact with the case body 3 to the state in which the
The assembling workability after the (2 ′) is disposed in the insertion hole 11 (11 ′) can be improved.

Further, by forming locking claws (first locking portions) 10 and locking holes (second locking portions) 14 on the case body 3 and the circuit board 4, respectively, the electrode leads 2 (2 ')
The case body 3 can be disposed and fixed on the circuit board 4 while maintaining the state in which the case body 3 is separated from the case body 3.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the accompanying drawings.

FIG. 1 is a perspective view showing a mounting structure of a liquid crystal display element according to a first embodiment of the present invention, FIG. 2 is a side view showing the liquid crystal display element according to the first embodiment, and FIGS. FIGS. 5 and 6 are views showing a mounting state of a liquid crystal display element according to a second embodiment of the present invention.

The first embodiment will be described with reference to FIGS.

The mounting structure of the liquid crystal display element according to the present invention includes a liquid crystal display element 1, electrode leads 2 for applying a voltage to the liquid crystal display element 1, a case body 3, and a circuit board 4.
And an illumination light source 5.

The liquid crystal display element 1 has liquid crystal sealed between a pair of translucent substrates, and a liquid crystal display element 1 is provided with a selective voltage application between electrodes formed on each of the translucent substrates. , And is controlled by the relationship with the polarization axes of the polarizing plates provided on both sides of the display unit, and is of a transmission type that performs a predetermined display using the illumination light of the illumination light source 5 provided behind. .

A plurality of electrode leads 2 are arranged in a row on one side in the longitudinal direction of the liquid crystal display element 1 by applying a voltage between the electrodes of the liquid crystal display element 1. As shown in FIG. 2, the electrode lead 2 is connected to an electrode portion (not shown) of the liquid crystal display element 1 and is lead-homed in a vertical direction X from a display surface 1a of the liquid crystal display element 1; 1
When the liquid crystal display element 1 is disposed on the mounting portion of the case 3 described later in detail, a predetermined pressure is applied to the groove of the case body 3 from the connection portion 2a of the electrode lead 2. (The angle at which it is applied and abuts) and is bent inward from the vertical direction X. Further, a stress absorbing portion 2b is formed in the vicinity of the connection portion 2a of the electrode lead 2 with the electrode portion to prevent the stress due to the deformation of the electrode lead 2 from being directly transmitted to the connection portion 2a. Further, a bent portion 2c which is formed to be bent outward at a predetermined angle (an angle at which the electrode lead 2 is easily guided to an insertion hole of the circuit board 4 described later) is formed at a tip portion of the electrode lead 2 on the circuit board 4 side. And a guide portion 2e which is formed to be bent in the vertical direction X again from the tip of the inclined portion 2d which is an extended portion from the bent portion 2c.

The case body 3 is made of, for example, P.O. It is formed of a resin material such as P and is made of a housing. This case body 3
A frame-shaped mounting portion 6 for disposing the liquid crystal display element 1 is formed at the upper end of the case body 3 and a plurality of groove portions (partition portions) 7 for disposing the electrode leads 2 at a distance from each other. The provided holder portion 8 is formed on the entire surface of the case body 3. The electrode lead 2 is disposed in the groove 7 of the holder 8 such that the electrode lead 2 comes into contact with the liquid crystal display element 1 when the liquid crystal display element 1 is disposed on the mounting section 6. A guide portion (not shown) for guiding the illumination light from the illumination light source 5 to the liquid crystal display element 1 is formed inside the case body 3, and the case body 3 is configured as a light box of the liquid crystal display element 1. Is done.

A pair of bosses (second bosses) corresponding to through holes of a circuit board 4 to be described later are provided at the lower end of the case body 3.
And a pair of locking claws (first locking portions) 10 provided adjacent to the boss body 9 and provided for fixing the case body 3 to the circuit board 4. It is formed extending toward the substrate 4.

The circuit board 4 is made of an insulating material such as paper phenol or a resin containing glass fiber. Insertion holes 11 penetrating the front and back of the circuit board 4 are formed in a row so as to correspond to the respective electrode leads 2. ing. A land portion 12 that is electrically connected to the electrode lead 2 is formed around the insertion hole 11 on the back surface side of the circuit board 4. The circuit board 4 has a through-hole (the first hole) corresponding to the boss 9 of the case body 3.
And a locking hole (second locking portion) 14 corresponding to the locking claw 10 of the case body 3. The circuit board 4 is provided with a mounting hole 15 for the illumination light source 5 disposed from the back side of the circuit board 4.

The illumination light source 5 is composed of, for example, an incandescent light bulb such as a tungsten lamp, and emits a light beam for illuminating the liquid crystal display element 1.

Next, the mounting structure of the liquid crystal display element 1 in the first embodiment will be described with reference to FIGS.

The electrode lead 2 of the liquid crystal display element 1 arranged on the mounting portion 6 of the case body 3 is held in a state of contacting the groove 7 of the case body 3. First, the guide portion 2e of the electrode lead 2 is disposed in the insertion hole 11 of the circuit board 4 as shown in FIG.
(A). " In this case, the electrode lead 2 remains in contact with the groove 7 of the case body 3. "FIG. 3 (b)".

Next, the boss 9 of the case 3 is connected to the circuit board 4.
When the engaging claw 10 of the case body 3 is engaged with the engaging hole 14 of the circuit board 4 while the electrode lead 2 is inserted (engaged) into the through hole 13, the electrode lead 2 moves from the guide portion 2 e to the inclined portion 2 d. Are inserted through the insertion hole 11 and the bent portion 2c is held in a state of contacting the wall of the insertion hole 11 (FIG. 4A). The electrode lead 2 in this case has a bent portion with a connecting portion 2a as a fulcrum, and has an inclination of a distance W1 from the wall of the insertion hole 11 to the vertical direction X of the electrode lead 2 before being inserted into the insertion hole 11. 2c is disposed in the insertion hole 11, so that the case 3
The state is shifted from the state of contact with the groove 7 to the state of separation (FIG. 4B). Therefore, the electrode lead 2 is
It can be soldered to the land portion 12 of the circuit board 4 in a state where it is separated from the land portion 12.

In this embodiment, when the boss 9 of the case body 1 is inserted into the through hole 13 of the circuit board 4, the electrode lead 2 is moved to a position separated from the groove 7 by an insertion. The distance W1 from the wall of the hole 11 to the vertical direction X of the electrode lead 2 before insertion into the insertion hole 11, that is, the distance W1 from the bottom of the groove 7 to the wall of the insertion hole 11, and the electrode lead 2 is inserted into the insertion hole. It is important to set the angle θ1 at which the slanted portion 2d guides the electrode lead 2 to the bent portion 2c when the electrode lead 2 is inserted into the bent portion 2c.

In the first embodiment described above, the guide portion 2e of the electrode lead 2 is inserted into the insertion hole of the circuit board 4 with the electrode lead 2 abutting on the groove 7 formed in the case body 3 and held in the case body 3. 11 and the boss body 9 provided on the case body 3 is inserted through the through hole 16, the electrode lead 2 is
And the inclined portion 2 d is inserted into the insertion hole 11, and the bent portion 2
Since “c” is disposed in the insertion hole 11, the electrode lead 2 can be held on the circuit board 4 in a state where the electrode lead 2 is separated from the case body 3. Therefore, since the electrode leads 2 can be disposed and fixed on the circuit board 4 in a state where the electrode leads 2 are not in contact with the case body 3 (the electrode leads 2 are free), the ambient temperature changes and the heat between the case body 3 and the circuit board 4 becomes high. Even when stress distortion occurs due to a difference in expansion coefficient, the electrode lead 2 does not fluctuate with the case body 3, so that the stress distortion in the soldered portion between the land 12 of the circuit board 4 and the electrode lead 2 is obtained. Can be suppressed as compared with the conventional structure, so that the occurrence of solder cracks can be eliminated.

Further, a through hole 13 penetrating through the front and back of the circuit board 4 and a boss body 9 extending from the case body 3 are provided. The electrode lead 2 can be shifted from a state in which the electrode lead 2 is in contact with the electrode
1 can improve the assembly workability.

Further, by forming a locking claw 10 on the case body 3 and a locking hole 14 on the circuit board 4, respectively, the electrode lead 2 is kept away from the case body 3 while the case body 3 is kept separated. Can be arranged and fixed on the circuit board 4.

Next, a second embodiment will be described with reference to FIGS. 5 and 6, but the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the second embodiment, the liquid crystal display element having the electrode leads 2 arranged in rows on one side is used in the first embodiment, whereas the electrode leads arranged in rows are arranged on both sides. This is different from the first embodiment in that a liquid crystal display element provided is used.

The mounting structure in the second embodiment will be described.
The electrode leads 2, 2 ′ on both sides of the liquid crystal display element 1 arranged on the mounting portion 6 of the case body 3 are connected to the respective grooves 7,
It is held in a state of contact with 7 ′. First, the guide portions 2e and 2e 'of the electrode leads 2 and 2' on both sides are disposed in the insertion holes 11 and 11 'of the circuit board 4 (FIG. 5A).
In this case, the electrode leads 2, 2 ′ on both sides remain in contact with the respective grooves 7, 7 ′ of the case body 3. "Figure 5
(B) "

Next, when the boss body 9 is inserted into the through hole 13 and the locking claw 10 and the locking hole 14 are engaged,
The electrode leads 2, 2 ′ on both sides are inserted from the guide portions 2 e, 2 e ′ to the inclined portions 2 d, 2 d ′ into the insertion holes 11, 11 ′, and the bent portions 2 c, 2 c ′ are formed in the insertion holes 11, 11 ′. FIG. 6A is held in a state of contact with the wall. In this case, the electrode leads 2, 2 ′ on both sides are connected from the walls of the insertion holes 11, 11 ′ with the connection portions 2 a, 2 a ′ as fulcrums.
11 ', the vertical direction X of the electrode leads 2, 2' before insertion,
Since each bent portion 2c, 2c 'is disposed in each of the insertion holes 11, 11' so as to have an inclination corresponding to the distances W1, W2 to X ', each groove 7, 7' of the case body 3 is provided. The state is shifted from the state of contact with the state to the state of separation (FIG. 4B). Therefore, the electrode leads 2 and 2 ′ on both sides can be soldered to the lands 12 and 12 ′ of the circuit board 4 while being separated from the case body 3.

In the second embodiment described above, the electrode leads 2 and 2 ′ on both sides can be disposed on the circuit board 4 with the electrode leads 2 and 2 ′ on both sides separated from the case body 3 as in the first embodiment.
A mounting structure of the light emitting display element which can eliminate the occurrence of solder cracks can be obtained. In the second embodiment, the boss 9 of the case 1 is connected to the through-hole 13 of the circuit board 4.
The electrode leads 2, 2 'are inserted into the grooves 7, 7'.
In order to shift to the position away from the insertion hole 11,
Distances W1, W2 from the wall of 11 'to the vertical directions X, X' of the electrode leads 2, 2 'before insertion of the insertion holes 11, 11'.
When the electrode leads 2, 2 'are inserted into the insertion holes 11, 11', the inclined angles 2d, 2d 'guide the electrode leads 2, 2' to the bent portions 2c, 2c ', and the guiding angles θ1,. θ
Setting with 2 becomes important.

The partition in each of the above embodiments is
Although each electrode lead 2 (2 ') is constituted by the groove 7 (7') which is arranged in the case body 3 with a space therebetween, for example, each electrode lead 2 (2 ') separates a protruding portion projecting from the case body. And the electrode leads 2
(2 ') may be constituted by an insertion hole for disposing the (2') apart, and the partition part in the present invention is not limited to this embodiment.

In each of the above-described embodiments, the case 3
The locking claw 10 is formed on the circuit board 4 and the locking hole 14 is formed on the circuit board 4. For example, a pair of locking claw (first locking portion) is provided on the circuit board 4 side, and the case body 3 is formed. May be provided with a groove (second locking portion) corresponding to the locking claw.

Further, the case body 3 of each of the above-described embodiments has a partition portion including a groove portion 7 (7 ') for disposing the electrode leads 2 (2') at a distance. However, in the present invention described in claim 1, it is not always necessary to provide a partition.

In each of the above embodiments, the case 3
A boss body 9 is provided on the circuit board 4 and a through hole 13 is provided on the circuit board 4 to engage the respective parts. For example, a positioning pin (first positioning section) is provided on the circuit board 4 side.
A hole corresponding to the positioning pin (the second
The first and second positioning portions according to claim 1 are not limited to the present embodiment.

In each of the above-described embodiments, the bent portion 2c (2c ') of the electrode lead 2 (2') is disposed in the insertion hole 11 (11 ') of the circuit board 4. Hole 1
Even if the length and forming shape of the electrode lead 2 (2 ') are changed so as to penetrate the bent portion 2c (2c') from 1 (11 '), the same effects as in the above embodiments can be obtained.

[0040]

According to the present invention, since the electrode leads can be mounted on the circuit board in a state where they are separated from the case body on which the liquid crystal display element is provided, cracks due to stress distortion in the soldered portion between the circuit board and the electrode leads can be obtained. Can be prevented.

A first positioning portion is provided on the circuit board, and a second positioning portion is provided on the case body.
Since the electrode leads can be shifted from a state in which the electrode leads are in contact with the case body to a state in which the electrode leads are separated by simply engaging the respective parts, the electrode leads are provided in insertion holes formed in the circuit board. After that, the assembling workability can be improved.

Further, the first and second locking portions are formed on the case body and the circuit board, and the electrode leads are separated from the case body by engaging the respective locking portions. The case body can be disposed and fixed on the circuit board while maintaining the state.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a mounting structure of a liquid crystal display element according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a forming state of electrode leads in the liquid crystal display element of the present invention.

FIG. 3 is a diagram showing a mounting state of the first embodiment.

FIG. 4 is a diagram showing a mounting state of the first embodiment.

FIG. 5 is a diagram showing a mounting state of a second embodiment of the present invention.

FIG. 6 is a diagram showing a mounting state of the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display element 2, 2 'Electrode lead 2a, 2a' Connection part 2b, 2d 'Stress absorption part 2c, 2c' Bend part 2d, 2d 'Inclined part 2e, 2e' Guide part 3 Case body 4 Circuit board 6 mounting Mounting part 7, 7 'Groove part (partition part) 8, 8' Holder part 9 Boss body (second positioning part) 10 Locking claw (first locking part) 11, 11 'Insertion hole 12, 12' Land Part 13 Through-hole (first positioning part) 14 Locking hole (second locking part)

Claims (4)

[Claims] 1. A liquid crystal display device, a case body having a mounting portion for mounting the liquid crystal display device, and a liquid crystal display device, wherein the liquid crystal display device is arranged in a row. When disposed on the electrode lead disposed in contact with at least a part of the case body, and an insertion hole for inserting the electrode lead is formed and electrically connected to the electrode lead, and A circuit board on which the case body is provided, a first positioning portion provided on the circuit board, and a position provided on the case body, the position of the case body relative to the circuit board being determined, and the first positioning A second positioning portion that engages with the portion, a guide portion formed at the distal end portion of the electrode lead, for guiding the electrode lead into the insertion hole, and a rear portion formed from the guide portion, and the positioning portion includes: When engaged A bent portion for shifting the electrode lead from a state in which the electrode lead is in contact with the case body to a state in which the electrode lead is separated from the case body, the mounting structure of the liquid crystal display element. 2. The mounting structure for a liquid crystal display element according to claim 1, wherein said case body includes a partition for disposing said electrode leads at a distance from each other. 3. The first positioning portion is a through hole penetrating the front and back of the circuit board, and the second positioning portion is a boss extending from the case body. The mounting structure of a liquid crystal display element according to claim 1 or 2, wherein the mounting structure is engaged with a boss body. 4. The method according to claim 1, wherein the case body and the circuit board have first and
The mounting structure of a liquid crystal display element according to claim 1, wherein a second locking portion is formed, and the locking portions are engaged with each other.