JPS6222069Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The invention is applicable to, for example, the tester bar of an electric circuit tester that measures electrical resistance, voltage, current, etc., or the pattern part of a printed circuit board (P/C board). Conductive contact needle devices used for applications such as conductive contact pins that perform electrical measurement adjustment or operation tests by contacting with The present invention relates to a conductive contact needle device suitable for use in measuring parts.

[Technical background of the invention and its problems]

As shown in FIG. 3, this type of conductive contact needle device that has already been proposed includes a stylus body b having a stylus (probe) b ₁ in a lower opening a ₁ of a conductive holding cylinder a. The stylus is slidably fitted in a locking part c formed on a part of the holding cylinder a so as not to fall off, and the spherical body is fitted on the inclined surface d formed on the upper part _b2 of the stylus main body b. (Ball) e is pressed into contact with the elasticity of a coil spring f interposed in the holding cylinder a.

When the above-mentioned conductive contact needle device is used as an electric circuit tester, for example, by bringing the stylus b ₁ of the stylus body b into contact with the solder part of a printed circuit board, electrical measurement can be performed.・Performing adjustments and operation tests. In this case, the stylus body b
The upper part _b2 pushes the inclined surface d sideways by the pressing force of the sphere e biased by the elasticity of the coil spring f, and thereby the inner wall of the conductive holding cylinder a It is designed to be electrically connected by being pressed against it.

However, since the conductive contact needle device described above has a coil spring f built into the holding cylinder a, the device configuration is large in diameter and long, and there are certain limitations on miniaturization of the pin configuration. Further, the more the stylus main body b is pushed in, the higher the spring pressure becomes, making the contact resistance unstable, and there is a limit to the durability of the coil spring f due to repeated loads. Furthermore, the current from the stylus body b may flow not only through the holding cylinder a but also through the coil spring f, which poses certain limitations on the application in connection with the instability of the contact resistance. There is.

[Purpose of invention]

This idea was made in view of the current situation,
It is an object of the present invention to provide a conductive stylus device in which the outer diameter of the pin can be significantly reduced and shortened, and the contact resistance can be stabilized to improve and stabilize measurement accuracy. purpose.

[Summary of the idea]

As a means to achieve the above object, the present invention uses compressed air supplied into the holding cylinder instead of the conventional coil spring as a means for urging the stylus main body attached to the holding cylinder to the projecting side. It is characterized by what it did.

[Example of idea]

An embodiment of the present invention will be described below with reference to FIG.

In the figure, reference numeral 1 denotes a conductive holding cylinder, and a lead wire 2 is electrically conductive and airtightly fixed to an upper end constriction part 1a of the holding cylinder 1, and a lower end opening 1b of the holding cylinder 1. A stylus main body 3 having a sharpened stylus (probe) 3a is slidably fitted in the stylus main body 3.
b and the lower part 3c form a large diameter part, and a small diameter part 3d is formed in the middle thereof.

Further, an annular locking portion 4 is formed in a part of the holding cylinder 1 where the upper large diameter portion 3b of the stylus main body 3 is located, and this locking portion 4 is formed by an inwardly pushed portion.
holds the stylus main body 3 so that it does not fall off.

Furthermore, an oblique groove 5 is formed on the upper top surface of the stylus main body 1, extending in the radial direction through the center and having a bottom inclined to one side.

The holding cylinder 1 configured in this way has, for example, 3
A set of books is held on a pinboard 6 at required intervals.

The pin board 6 is formed of an insulating material or a conductive material coated with an insulating material, and is adapted to hold the three holding cylinders 1 in a mutually electrically insulated state.

This pin board 6 is also provided with an air flow path 7 that also serves as an air reservoir, and the compressed air supplied to this air flow path 7 via the introduction pipe 8 is transferred to each of the holding cylinders. 1 to press and bias each stylus main body 3 toward the protruding side. Further, each stylus main body 3 receives the pressure of this compressed air in the diagonal groove 5 and is also pressed in the radial direction,
It is designed to always be in contact with the holding cylinder 1 having conductivity in a conductive state.

The introduction pipe 8 is connected to an air generator (not shown) having, for example, a compressor, a pressure regulator, and a filter, and brings each stylus body 3 into contact with, for example, the solder portion _W1 of the printed circuit board W. The so-called contact pressure can be changed arbitrarily by adjusting the pressure of the compressed air supplied from the air generator.

In the above configuration, when using this device as an electric circuit tester, compressed air from an air generator (not shown) is supplied to the inlet pipe 8, the air flow path 7,
and is guided into each holding cylinder 1 through the hole 9. Then, each stylus main body 3 is pressed toward the protruding side by the biasing force of the compressed air, and the stylus 3a comes into contact with, for example, the solder portion _W1 of the printed circuit board W, and measurement is performed.

According to this structure, compressed air is used as a means for pressing and biasing the stylus body 3 toward the protrusion side, unlike conventional ones, without using a coil spring. The dimensions can be made extremely small. In addition, as a result, the holding cylinder 1
Since the mutual spacing between the stylus elements 3a, that is, the mutual spacing between the stylus elements 3a, can be made extremely narrow, it can be easily applied to measurements of high-density circuit boards, ultra-LSIs, ICs, etc., and measurements of other electronic components with extremely small pitches. be able to.

In addition, since a coil spring is not used, the current from the stylus body 3 is transmitted to the lead wire 2 only through the holding cylinder 1, which not only lowers the inherent resistance value but also provides stability during operation. This ensures that measured values can be accurately transmitted to meters, etc. that display minute current changes in objects under test for continuity testing, such as IC circuits. Furthermore, by not using a coil spring, it is possible to extend the life of the device.

Furthermore, since the stylus body 3 is biased with compressed air, the biasing force is always constant regardless of the sliding position of the stylus body 3, making it possible to stabilize the contact resistance. Since the air flow path 7 inside also serves as an air reservoir, fluctuations in the biasing force can be further reduced.

FIG. 2 shows another embodiment of the present invention, in which a stylus main body 3 is fitted to both ends of each holding cylinder 1 held on a pin board 6.
Even with this configuration, similar effects can be expected.

In both of the embodiments described above, the stylus main body 3 is provided with the diagonal groove 5, but the same effect can be obtained by cutting the end face diagonally instead.

[Effect of idea]

As explained above, in the present invention, the stylus main body is pressed and biased by compressed air without using a coil spring, so the outer diameter of the holding cylinder can be reduced to 0.2 mm or less. The pitch of the needles can be adjusted to be suitable for high-density substrates and the like. In addition, by using compressed air, it is possible to stabilize the contact resistance and extend the lifespan, and since the current from the stylus body is transmitted only through the holding cylinder,
Measurement accuracy can be improved and stabilized.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
Figure 3 is a partial sectional view showing another embodiment of the present invention.
The figure is a sectional view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Holding cylinder, 1b... Opening, 3... Stylus body, 3a... Stylus, 5... Diagonal groove, 6...
Pin board, 7...air flow path, 9...hole.

Claims (1)

[Claims for Utility Model Registration] 1. At least one conductive holding cylinder, a pin board for insulating and holding the holding cylinder, and a pin board that is slidably fitted into the opening of the holding cylinder without falling out. a means for connecting the inside of the holding cylinder to a compressed air source so as to bias the stylus main body in a direction to protrude from the holding cylinder; and a holding member provided in the stylus main body; A conductive contact needle device comprising: a diagonal portion that brings the outer surface of the stylus main body into contact with the inner surface of the holding cylinder by the pressure of compressed air within the cylinder. 2. The conductive contact needle device according to claim 1, which is a registered utility model, characterized in that the inner end of the stylus main body is provided with a diagonal cut portion or a diagonal groove to form a diagonal portion. 3. The inside of the holding cylinder is connected to a compressed air supply source through an air passage provided in the pin board and serving as an air reservoir, and a hole provided in the holding cylinder and communicating with the air passage. Scope of utility model registration claims Paragraph 1 or Paragraph 2
Conductive contact needle device as described in . 4. The conductive contact needle device according to claim 1, 2, or 3 of the utility model registration, characterized in that the stylus body is fitted to both ends of the holding cylinder, respectively.