JPH09218220A - Probe unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a shortcircuit of probes surely at low cost by using an alumite coating as an insulating material between the probes and a mounting memory. SOLUTION: A probe unit 1 is constituted of a plate-like mounting member 2 and a plurality of probes 3 generating and fixed to the mounting member 2. The mounting member 2 is formed of Al, having mounting holes 4 for mounting of the probes 3 penetrating at predetermined positions. The probe 3 consists of a pipe-shaped base body 6 and a contact element 7 which are both formed of Al. An alumite coating 9 is formed at a part of the mounting member 2 in touch with the probe 3, namely, all over an inner wall face of each mounting hole 4 by anodic oxidization or the like manner. The alumite coating 9 has superior insulating properties. Since the alumite coating 9 is interposed between the probe 3 and mounting hole 4, the probe 3 is electrically insulated from the mounting member 2, and the probes 3 are insulated from each other and prevented from being shortcircuited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe unit used for continuity inspection of electronic parts mounted on a printed circuit board or the like.

[0002]

2. Description of the Related Art As shown in FIGS. 2 (a) and 2 (b), a probe unit (21) comprises a plate-like mounting member (22) having a plurality of parallelly arranged probes (23) fixed therethrough. ,
A contact (27) provided at the tip of the probe (23) is brought into contact with an object to be inspected such as a printed circuit board, and each probe (23)
A predetermined voltage is applied to a lead wire (not shown) attached to the upper end of the device to conduct a continuity test of the device under test. The upper end of the contact (27) is attached to the probe (2
It is housed via a spring (28) in a housing portion (25) provided at the lower end of the base body (26) of 3), whereby the contactor (27) elastically moves along the axial direction of the probe (23). It is supposed to be displaceable.

In this probe unit (21), each probe (23) is formed of a conductive metal material. On the other hand, the mounting plate (22) is formed of an insulating material such as bakelite or a plastic material in order to prevent a situation in which an inspection cannot be performed due to a short circuit between the probes or an electronic component such as an IC is destroyed. Has been done.

[0004]

By the way, during the continuity inspection by the probe unit, the mounting member is strongly pressed against the printed circuit board side in order to obtain a constant contact pressure at the inspection location. In this case, since a pressing force is applied to the mounting member at each inspection, when repeatedly inspected, the mounting member warps or deforms due to repeated load, and further, chipping or cracking occurs due to aging change. There is a risk. Also, the probe is replaced regularly, but because the mounting member is made of a material with poor abrasion resistance such as Bakelite, when the probe is inserted and removed during replacement, The holes are prone to wear, which tends to shorten the life of the mounting member.

[0005] In order to solve such a problem,
As shown in FIG. 3, the mounting member (22) is formed of a metal material such as aluminum, and the probe (23) is fitted with a cylindrical sleeve (29) formed of an insulating material such as resin, A structure that insulates between the probe (23) and the mounting member (22) is also conceivable, but this requires a new component (sleeve) and increases the number of assembling steps, resulting in high cost. Further, since a minimum interval of twice the wall thickness of the sleeve is required between adjacent probes, it may not be possible to cope with the narrowing of the measurement pitch due to the recent increase in circuit complexity and density.

Therefore, according to the present invention, the probe unit can surely prevent short-circuiting between the probes, the life of the mounting member can be improved, and the cost is low, and the probe unit can cope with complicated and high-density circuits. The purpose is to provide.

[0007]

In order to achieve the above object,
In the present invention, in a device including a mounting member and a plurality of probes fixed to the mounting member, one of the mounting member and the probe is made of an aluminum material, and the member made of the aluminum material. Of at least the other member, an alumite coating film is formed.

Further, in a device including a mounting member and a plurality of probes fixed to the mounting member, the mounting member and the probe are made of an aluminum material, and an alumite coating is interposed at least at a contact portion between the both. .

In this case, the alumite coating may be formed on either one or both of the mounting member and the probe.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIG.
A description will be given based on (a) and (b).

As shown in FIG. 1, a probe unit (1) according to the present invention comprises a plate-shaped mounting member (2) and a plurality of probes (3) fixed through the plate-shaped mounting member.

The mounting member (2) is made of an aluminum material, and a mounting hole (4) for mounting the probe (3) is formed at a predetermined position of the mounting member (2).

The probe (3) is a pipe-shaped substrate (6).
And a contactor (7) having a smaller diameter than the base body (6) and a conical tip. Both the base body (6) and the contactor (7) are made of a conductive material such as an aluminum material. At the lower part of the base body (6), a locking part (6a) that is reduced in diameter toward the inner diameter side over the entire circumference thereof.
Is provided. In the space (5) below the locking portion (6a) in the internal space of the base body (6), the base side of the contactor (7) is slidably accommodated via a spring (8). The upper end side of (8) is locked by the locking portion (6a). As a result, at the time of inspection, a constant contact pressure is applied between the contactor (7) and the object to be inspected by the elastic force of the spring (8).

The probe (3) of the mounting member (2)
An alumite coating (9) is formed by a known means such as anodic oxidation treatment on the portion contacting with, that is, the entire inner wall surface of the mounting hole (4) (the thickness of the coating is exaggerated in the drawing. Exist). The thickness of the alumite coating (9) at this time is arbitrary, but is preferably about 10 to 200 μm.

After the alumite coating (9) is formed in the mounting hole (4) in this manner, each probe (3) is inserted into the mounting hole (4) and fixed to each other with an appropriate fitting tolerance. The probe unit (1) shown in 1 (a) is constructed. At this time, the lower end of the base body (6) is aligned with the lower surface of the mounting member (2), and the contact (7) is projected below the mounting member (2). After bringing the probe unit (1) close to the printed circuit board and bringing the contactor (7) into contact with the wiring pattern of the circuit board, the mounting member (2) is pressed toward the circuit board and a predetermined amount is applied to each probe (3). A test signal is sent to conduct a continuity test.

As is well known, the alumite coating (9) has excellent insulating properties. Therefore, as described above, the alumite coating (9) is provided between the probe (3) and the mounting hole (4).
Is interposed, the probe (3) and the mounting member (2) are electrically insulated from each other, whereby the probe (3)
Since they are insulated from each other, it is possible to prevent a short circuit of the probe (3). For example, when the film thickness of the alumite coating (9) is 10 μm, the withstand voltage is 200 v or higher, and the applied voltage (about 50 v) at the continuity test.
Since it is sufficiently larger than that of (1), good insulation can be secured. Further, since the alumite coating can be formed easily and inexpensively with the existing processing equipment, the manufacturing cost does not significantly increase.

The film thickness of the alumite coating (9) is much smaller than that of the sleeve (29) shown in FIG. Therefore, the arrangement pitch of the probes (3) can be made extremely small as compared with the case of using the sleeve, and the circuit becomes complicated.
It is possible to easily deal with higher density.

Furthermore, since the alumite coating (9) has excellent wear resistance, the attachment hole (4) will not be worn even if the replacement work of the probe (3) is repeated. Further, since the mounting member (2) is made of aluminum having higher rigidity than bakelite or the like, there is no possibility that the mounting member (2) will be deformed or chipped or cracked. Therefore, the life of the mounting member (2) can be remarkably improved as compared with the conventional product shown in FIG.

In the above construction, the mounting member (2) is made of aluminum and the alumite coating (9) is formed on the inner wall surface of the mounting hole (4).
Is sufficient if it is interposed at least in the contact portion between the mounting member (2) and each probe (3). Therefore, the probe (3) is made of aluminum and has a film thickness of 2 to 50 μm on its outer peripheral surface.
An alumite coating (9) of about m may be formed. Further, the alumite coating (9) may be formed not only on the contact portion with the mounting member (2) but also on the entire outer peripheral surface above it, thereby narrowing the measurement interval and lengthening the total length. Even with the probe (3), it is possible to reliably avoid a short circuit between the probes (3) due to deformation of the upper end portion. When the probe (3) is made of aluminum in this way, the mounting member (2) does not have to be made of aluminum, and may be made of another metal material having a certain strength.

The mounting member (2) and the probe (3)
Both may be made of aluminum and the alumite coating (9) may be formed on both.

The present invention is applicable to a probe unit (1) of any structure, regardless of the shape and structure of the probe (3) or the mounting member (2), the line and position of the probe (3), the number of arranged wires and the like. It is possible. Further, the location where the alumite coating (9) is formed is also arbitrary as long as it includes the contact portion between the mounting member (2) and each probe (3), and is formed on another portion (for example, the surface of the contactor). It doesn't matter.

[0022]

As described above, according to the present invention, since the alumite coating is used as the insulating material between the probe and the mounting member, it is possible to reliably prevent short-circuiting between the probes at low cost. it can. Further, as compared with the case where a sleeve made of resin or the like is used as the insulating material, the arrangement pitch of the probes can be made smaller, and it becomes possible to easily cope with the complexity and high density of the circuit. Furthermore, due to the wear resistance of the alumite coating, the mounting hole will not be worn even after repeated probe replacement work, and a metal material that is unlikely to be deformed, chipped, or cracked is used as the material for the mounting member. Therefore, the life of the mounting member can be remarkably improved as compared with the conventional product.

[Brief description of drawings]

FIG. 1 (a) is a vertical cross-sectional view of a probe unit according to the present invention, and FIG. 1 (b) is an enlarged cross-sectional view in the vicinity of the tip of a probe.

FIG. 2 (a) is a vertical cross-sectional view of a conventional probe unit, and FIG. 2 (b) is an enlarged cross-sectional view near the tip portion of the probe.

FIG. 3 is a vertical sectional view showing an improved example of a conventional probe unit.

[Explanation of symbols]

 1 probe unit 2 mounting member 3 probe 9 alumite coating

Claims (3)

[Claims] 1. A device comprising a mounting member and a plurality of probes fixed to the mounting member, wherein one of the mounting member and the probe is made of an aluminum material and is made of this aluminum material. A probe unit, wherein an alumite coating is formed on at least a contact portion of the member with the other member. 2. A mounting member comprising a mounting member and a plurality of probes fixed to the mounting member, wherein the mounting member and the probe are made of an aluminum material, and an alumite coating is interposed at least in a contact portion between the both. Characteristic probe unit. 3. The probe unit according to claim 2, wherein an alumite coating is formed on one or both of the attachment member and the probe.