JP3680295B2 - Extra fine contact probe - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to an ultrafine contact probe capable of precisely performing a trie inspection on a disconnection, a short circuit or the like of a substrate electrode or a pattern of a semiconductor, electronic device, liquid crystal or the like having a minute pitch interval.
[0002]
[Prior art]
Conventionally, an integrated contact probe has been used to check for disconnection, short-circuiting, etc. of an electric circuit of a printed wiring board.
[0003]
As shown in FIG. 1, the conventional integrated contact probe has a central conductor 2 fitted in a cylindrical sleeve 1, and a protrusion 4 formed at the rear end of the sleeve 1 and a rear end of the central conductor 2. Further, the coil spring 3 is fixed via the small sphere 5 so that the center conductor 2 can move relative to the sleeve 1 when the tip of the center conductor 2 is pressed against the surface to be measured of the printed circuit board. Has been.
[0004]
[Problems to be solved by the invention]
Since the pitch interval of printed circuit boards to be inspected has recently become very narrow, there is a need for developing probes that are thinner, more reliable, and have a longer life. There is a strong demand.
[0005]
This is because if the tip of the needle part moves even slightly, the tip of the needle part may hit an unmeasured surface. By forming the needle portion very finely, the clearance from the sleeve side is reduced in proportion to the needle portion, so that the gap with the sleeve can be reduced, so that the deflection of the tip of the needle portion is improved.
[0006]
Since the conventional contact probe shown in FIG. 1 requires the coil spring 3, there is a limit in reducing the diameter of the contact probe.
[0007]
An object of the present invention is to provide an ultra-fine contact probe that can be made significantly thinner than conventional probes and that can inspect a printed circuit board with a narrow pitch interval without hindrance. And
[0008]
Another object of the present invention is to provide a method for manufacturing an ultra-thin cylindrical body for manufacturing the ultra-fine contact probe.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present inventor has made extensive research and formed a contact probe made of an extra fine wire from an elastic material without using a coil spring, and formed a central portion of the wire in a thin plate. Then, the present inventors have arrived at the present invention by conceiving that the thin plate is given a role of a coil spring.
[0010]
In other words, the invention described in claim 1 of the present invention is that an extremely thin wire body having a needle portion at the tip is integrally provided with a thin plate formed with a concave or convex portion having a spring property, and A contact probe is formed by tightly fitting an ultra-thin cylindrical body, the width of the thin plate is smaller than the diameter of the ultra-thin cylindrical body, and it is easy to detach easily when a probe failure occurs, and further, the elastic force of the thin plate The needle portion is configured to be elastically movable in the front-rear direction.
[0011]
The present applicant has developed a contact probe in which a thin plate is connected to a linear body, and has previously filed a patent application. This achieves the object of the invention described in claim 1, but the swaging method is used. Since it was used and manufactured, it was not satisfactory in that it was not easy to manufacture.
[0012]
According to the present invention, the contact width of the thin plate can be made smaller than the diameter of the ultra-thin cylindrical body by simply pressing without using a swaging method by closely fitting the ultra-thin cylindrical body to the tip needle portion. The gist is that it can be easily manufactured.
[0013]
As described in claim 8, the extra-fine cylindrical body used in the present invention is made by inserting a core wire of an extra-fine linear body through an extra-fine cylindrical body made of gold or a gold alloy, and then passing the die. A semicircular groove having a diameter larger than that of the cylindrical body is struck up and down with a jig formed in the flat ultrathin cylindrical body clamping part, and then attached to a die, and the ultrathin linear body core is pulled. It can be manufactured by pulling out.
[0014]
By sandwiching and striking with a plate having a semicircular groove formed in this way, the gold or gold alloy is stretched and the inside diameter of the ultra-thin cylindrical body is increased. As a result, the inserted ultra-thin linear body (core metal) ) Can be attached to a die and removed.
[0015]
Next, embodiments of the present invention will be described with reference to the drawings.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 2 and 3 show an embodiment of the contact probe of the present invention, in which a very thin cylindrical body 7 is closely fitted to the very fine linear body 6, and a thin plate 8 is continuously connected to the same fine linear body 6. An example in which the ultrathin cylindrical body 7 portion is configured to be movable relative to a sleeve (not shown) by the elastic force of the thin plate 8 is shown. Note that the width of the thin plate 8 is slightly smaller (3 to 5 μ) than the diameter of the ultrathin cylindrical body 7.
[0017]
In order to give the thin plate 8 of the contact probe 9 the same elastic force as that of the coil spring, the ultrafine wire 6 is formed from a material having a spring property such as steel, a copper alloy, a gold alloy having a spring property, or tungsten. To do.
[0018]
The thin plate 8 is not a linear body, but is a thin plate. If the thin plate 8 is a linear body, it protrudes laterally beyond the diameter of the ultra-thin cylinder 7 and strongly contacts the sleeve to which the contact probe 9 is fitted. This is because the 7 part stops moving.
[0019]
The rear end portion 11 of the contact probe 9 may be connected to a lead wire, or may be abutted with the object to be measured as a double-end sliding contact probe by tightly fitting the ultra-thin cylinder 7.
[0020]
In the contact probe shown in FIG. 1, the outer diameter of the center conductor 2 is 0.11 or less, and it has been difficult to process into an ultra-precision tube having a uniform outer diameter and inner diameter. The outer diameter of the body (same as the central conductor) can be freely formed to 0.05 to 0.1 mm, preferably 0.04 to 0.08 mm.
[0021]
The thin plate 8 of the present invention becomes longer when the thickness of the probe becomes thicker, and becomes shorter when the probe becomes thinner. The length varies depending on the thickness, but the length is 2 to 6 mm, and the thickness is set to the probe outer diameter or the like. In proportion, it is preferable to be about 0.02 to 0.04 mm.
[0022]
In order to sufficiently impart the spring function to the thin plate 8 of the present invention, the concavo-convex part (concave part or convex part) 10 is formed . It is particularly preferable to form three or more uneven portions 10.
[0023]
As shown in FIG. 4, the contact probe 9 of the present invention can be used by slidingly fitting the plastic probe mounting base 12 in accordance with the number of pads of the device to be inspected without using a sleeve. it can.
[0024]
A through hole is formed in the probe mounting base 12, an extra-thin tubular portion is slidably fitted into the through hole, and a rear through hole into which the plunger receiving pipe 13 is press-fitted is fitted into the rear through hole. The end 11 is in contact. Since the tip of the plunger receiving pipe 13 is formed as a funnel-shaped guide, the rear end portion 11 of the contact probe can be easily brought into close contact with the plunger receiving pipe 13.
[0025]
The plunger receiving pipe 13 can be connected to a lead wire or an interface (connection of a power source or the like).
[0026]
The thin plate 8 is coated with an insulator for preventing contact between adjacent contact probe thin plates 8.
[0027]
As shown in FIG. 4, when the tip needle portion 14 comes into contact with the object to be measured 15 and is pressed, a wave shape (stroke) that expands and contracts substantially uniformly is generated by the pressing. The stroke amount is proportional to the number of the uneven portions 10.
[0028]
The pressing stroke at the time of contact is bent into a loose S-shape to the full outer diameter of the extra-thin cylindrical body 7 by pressing, and the entire length is shortened by the amount of bending. That is, the stroke required for the probe is obtained by the amount deformed into the S shape.
[0029]
Since the stroke of the contact probe 9 of the present invention is proportional to the length of the extra-thin cylindrical body 7, it can be adjusted and controlled by the length of the extra-fine cylindrical body 7.
[0030]
The contact probe 9 of the present invention can be coated with an insulating coating on the outer periphery, and a plurality of these contact probes can be housed in an external cylinder. When a plurality of contact probes are housed in a single sleeve in this way, current and voltage can be applied simultaneously, so that a more precise inspection can be performed.
Next, the manufacturing method of the contact probe of this invention is demonstrated.
[0032]
First, an ultrafine wire body 6 having a diameter of about 0.1 mm is formed from an elastic material having spring properties such as steel, copper alloy, or tungsten, and the ultrafine tube body 7 is fitted to the tip of the ultrafine wire body 6. . Since the fitting portion of the linear body 6 is slightly deformed, it cannot be removed after fitting.
[0033]
In order to fit the linear body 6 to the cylindrical body 7, the cylindrical body 7 is held by a jig, and the linear body 6 is fitted to the cylindrical body 7 by holding the moving member holding the linear body 6. Move to.
[0034]
Similarly, an extra-fine cylindrical body 7 having an inner diameter of 0.1 mm is tightly fitted to an extra-fine linear body 6 having a diameter of approximately 0.07 mm, and an extra-fine filament having an inner diameter of 0.08 mm is fitted to the extra-fine linear body 6 having a diameter of approximately 0.05 mm. The cylinder 7 was tightly fitted.
[0035]
Next, a ribbon spring-like thin plate having a thickness equal to or smaller than the outer diameter of the extra-thin cylindrical body 7, preferably about 0.03 to 0.08 mm, is obtained by pressing the ultra-thin linear body continuously provided in the extra-fine cylindrical body. 8 is processed.
[0036]
At this time, the width of the thin plate 8 is slightly negative from the outer diameter of the ultrathin cylindrical body. For example, when the outer diameter of the ultrathin cylinder is 100, the width of the thin plate is preferably about 80 to 95.
[0037]
Next, in order to effectively impart the spring function, the uneven portion 10 is formed to obtain the contact probe of the present invention shown in FIGS.
[0038]
The ultra-thin cylinder 7 used in the present invention is manufactured from gold or a gold alloy. This is because gold or a gold alloy is excellent in conductivity and softens and stretches thinly when struck, so that an ultrathin cylindrical body having a thin wall thickness can be formed.
[0039]
In the method of putting the cored bar into the pipe and pulling it out, the limit was to form the cylindrical body 7 having an inner diameter of 0.5 mm.
[0040]
If a cylinder having an inner diameter of 0.5 mm and an outer diameter of 0.6 to 0.7 mm is passed through a known drawing die a plurality of times without inserting a core linear body, the inner diameter is 0.2 mm and the outer diameter is 0.3 mm. Can be formed.
[0041]
This is the limit that can be reduced by passing the die through the cylinder having an inner diameter of 0.5 mm a plurality of times. If an attempt is made to make it thinner than this, the center hole becomes unbalanced and a precise cylinder 7 cannot be obtained.
[0042]
When a linear body having a diameter of 0.1 mm is inserted into the ultrathin cylindrical body 7 formed as described above and the die is passed through to bring the cylindrical body 7 into close contact with the core, the thickness can be further reduced. . The linear body can be inserted into the cylindrical body 7 by holding the cylindrical body 7 with a jig in the same manner as described above and moving and fitting the moving member holding the linear body.
[0043]
It has been impossible with the conventional method to pull out the ultrathin cylindrical body 7 thinned as described above from the core linear body.
[0044]
According to the present invention, the ultrathin cylindrical body 7 with the core inserted between the plates having a semicircular groove having a larger diameter than the ultrathin cylindrical body is sandwiched and struck, and then slightly larger than the inner diameter of the ultrathin cylindrical body 7. If the extra-thin tubular body 7 is pulled by holding it with a jig that forms a hole slightly smaller than the outer diameter, it can be extracted as the extra-thin tubular body 7 having the necessary roles of an inner diameter of 0.1 mm and an outer diameter of 0.13 mm. .
[0045]
When this is further extracted with a drawing die, an ultrathin cylindrical body 7 having an inner diameter of 0.07 mm and an outer diameter of 0.1 mm can be formed.
[0046]
Furthermore, when this is extracted with a drawing die, a precise ultra-thin cylindrical body 7 can be formed in the order of an inner diameter of 0.05 mm and an outer diameter of 0.08 mm.
[0047]
According to the present invention, since the role of the stroke equivalent to that of the coil spring is given by forming the thin plate portion having the spring property, the contact probe can be formed significantly thinner than the conventional one.
[0048]
Anyone wants to make the contact probe thinner, but it has never been possible in the past to actually obtain an ultra-fine ultra-precise product like the present invention.
[0049]
In addition, according to the present invention, a thin plate having a width equal to or smaller than the outer diameter of the cylindrical body is formed by simply pressing the central linear body by fitting the ultrathin cylindrical body to the tip of the ultrathin linear body. Therefore, the contact probe of the present invention can be formed very easily.
[0050]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the contact probe can be made as fine as about half of the conventional one, inspection of printed circuit boards having a narrow pitch interval can be performed without any trouble. In addition, the tip needle part is difficult to move from the center, so this type of conventional contact probe that can effectively avoid the risk of the tip hitting an object to be measured is not seen at all. Play.
[0051]
Further, according to the invention described in claim 8, it is possible to easily manufacture an ultrathin cylindrical body that could not be manufactured conventionally. By using this ultrathin cylinder, the contact probe of the present invention can be formed very easily.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a conventional integrated contact probe.
FIG. 2 is a cross-sectional view showing a contact probe of the present invention.
FIG. 3 is a longitudinal sectional view showing another example of the contact probe of the present invention.
FIG. 4 is a cross-sectional view showing a state in which the contact probe of the present invention is mounted on a mounting base.
[Explanation of symbols]
6 ··············································································································· ……… The rear part of the contact probe

Claims (7)

A thin plate having a concave portion or a convex portion having a spring property is integrally connected to an extremely fine wire body having a needle portion at the tip, and a contact probe is formed by closely fitting the ultrafine tube body to the ultrafine wire body, The ultra-thin contact probe is characterized in that the width of the thin plate is narrower than the diameter of the ultra-thin cylindrical body, and the needle portion can be elastically moved in the front-rear direction by the elastic force of the thin plate. The contact probe according to claim 1, wherein a diameter of the extra fine wire is 0.05 to 0.1 mm. The contact probe according to claim 1 or 2, wherein the ultrafine wire is formed from steel, a copper alloy, a gold alloy having spring properties, or tungsten. The contact probe according to any one of claims 1 to 3, wherein the extra-fine cylindrical body is formed from gold or a gold alloy. The contact probe according to any one of claims 1 to 4, wherein the thin plate of the contact probe is covered with an insulating film, and a plurality of the contact probes are internally provided in a sleeve. The contact probe according to claim 5, wherein uneven portions are alternately formed on the thin plate. The ultrathin cylindrical body is tightly fitted to the tip of the ultrathin linear body made of a material having a spring property, and the ultrathin linear body connected to the ultrathin cylindrical body tightly fitting portion is pressed to form the thin plate. The method of manufacturing a contact probe according to claim 1.

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