JPH045011Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a contact probe that is used by being inserted into a pin board of a circuit board inspection machine or a mounted board inspection machine that inspects integrated circuits, for example.

[Technical background of the invention and its problems]

As shown in FIGS. 6 and 7, this type of contact probe that has already been proposed has an opening 1a at one end of a conductive sleeve 1 having a cylindrical shape with a bottom.
Connect the plunger contact pin 2 to the extensible coil spring 3
The sleeve 1 is provided so as to be slidable therebetween, and a stopper 4 formed by drawing on a part of the sleeve 1 prevents the sleeve from slipping out.

Therefore, the above-mentioned contact probe is designed to test the continuity of the object to be tested by bringing the contact portion 2c of the plunger contact pin 2 into contact with the object to be tested.

In this way, the contact probe described above has a sliding part (sliding part) 2b of the plunger contact pin 2.
Since there is a very small gap between the sleeve 1 and the plunger contact pin 2, there is a risk of contact failure. . Further, there is a risk that dust and the like may enter the space C, causing contact continuity failure, and significantly reducing the reliability of the continuity test.

Therefore, the present applicant previously proposed a contact probe shown in FIG.

That is, in the contact probe shown in FIG. 8, a conductive sleeve 1 is inserted into a socket 6 of a pin board 5, and a plunger contact pin 2 having a contact portion 2c is inserted into an opening 1a of the sleeve 1 by a coil spring 3. The plunger contact pin 2 is slidably inserted into the retaining portion 1 of the opening 1a.
A center conductor 7 made of, for example, a conductive wire is stretched between the inner end 2d of the plunger contact pin 2 and the other end of the sleeve 1, and This central conductor 7 is formed into a bypass circuit.

Therefore, in the above-mentioned contact probe, when inspecting an object to be inspected, the current from the contact portion 2c of the plunger contact pin 2 flows from the center conductor 7 to the other end 1d of the sleeve 1 to feed a power supply socket (not shown). On the other hand, the current from the contact portion 2c flows through the inner wall of the sleeve 1 to the other end 1d of the sleeve 1 and is connected to the power supply socket. It is designed to conduct to the inspection machine.

In this way, the contact probe described above has two
Since the current passes through the bypass circuit of the center conductor 7, which constitutes a conduction circuit and has low resistance, stable conduction and contact conduction are maintained for a long period of time. However, the inner diameter of the sleeve 1 is approximately 1.0 mm. Therefore, when the plunger contact pin 2 slides, the conductive wire as the center conductor 7 buckles, and the coil spring 3 surrounding the center conductor 7 causes the center conductor 7 to buckle. They may get pinched or become entangled with each other, which may eventually cause them to break or cause current to flow across the coil spring 3, resulting in a high resistance value. Since the coil spring 3 is interposed in the sleeve 1, the assembly work is troublesome, and the center conductor 7 as a conductive wire is required to have high precision in length, strength, etc., which increases the cost. There are other difficulties.

[Purpose of invention]

The present invention was developed in view of the above-mentioned circumstances, and by arranging a coil spring on the outside of the sleeve, even if the conductive core is buckled by the conductive wire, it can be prevented from breaking. The present invention provides a contact probe that is intended to perform stable continuity tests over a long period of time and to improve reliability.

[Summary of the idea]

In this invention, a coil spring is arranged around the outer periphery of a cylindrical sleeve having a pair of upper and lower flanges.
A pair of holes in the axial direction are bored in a part of this sleeve, and a plunger contact pin is slidably fitted into the opening of the sleeve with the contact portion protruding outward. An engaging pin provided through the hole and the plunger contact pin is engaged with one end of the coil spring to bias it outward, and the inner end of the plunger contact pin and the other end of the sleeve The conductive core is stretched with the elasticity of the coil spring,
This prevents disconnection and ensures stable continuity testing over a long period of time.

[Example of idea]

Hereinafter, the present invention will be described with reference to an illustrated embodiment.

In addition, the present invention will be described with the same reference numerals attached to the same constituent members as in the above-described specific example.

1 to 4, reference numeral 8 denotes a cylindrical sleeve having a pair of upper and lower flanges 8a and 8b inserted into the insertion hole 5a of the pin board 5. An extensible coil spring 9 is disposed on the outer periphery, and this coil spring 9
One end portion of the flange 8b is engaged with the flange 8b. Further, a pair of slots 10 are bored in the axial direction in a part of the sleeve 8 close to the flange 8a.
A plunger contact pin 11 is slidably fitted into the opening 8c with the contact portion protruding outward. Furthermore, an engagement pin 12 formed by a taper pin is provided to penetrate through both the strip holes 10 and the plunger contact pin 11, and this engagement pin 12 engages with one end of the coil spring 9. There is.

Therefore, although the plunger contact pin 11 is urged to protrude outward via the engagement pin 12 by the elasticity of the coil spring 9, the engagement pin 12 It is engaged with the terminal edge of the hole 10 and held so as not to slip out outward.

On the other hand, the inner end 1 of the plunger contact pin 11
A conductive core 13 made of, for example, a conductive wire is stretched between 1a and the other end 8d of the sleeve 8, and this conductive core 13 constitutes a bypass circuit.

Therefore, the contact probe of the present invention described above, as shown in FIG.
The current from the conductive core 13 to the sleeve 8
The current flows to the other end 8d, passes through a power supply socket (not shown), and conducts to the inspection machine connected to the lead wire, and the current from the contact portion 11b passes through the inner wall of the sleeve 8 to the other end 8b. It is designed to conduct to the above-mentioned inspection machine.

In particular, since the coil spring 9 is disposed outside the sleeve 8, there is no risk that the conductive core 13 will be pinched by the coil spring 9, and even if it buckles, it can be prevented from being damaged by cutting. , does not require precision in strength or length.

Next, in another embodiment of the present invention shown in FIG. A conductive core 13 is stretched between the inner end 11a of one plunger contact pin 11 and the inner end 11a of another plunger contact pin 11 slidably fitted into the other end opening 8c of the sleeve 8. The plunger contact pins 11 are provided in the openings 8c and 8e at both ends of the sleeve 8 with their contact portions protruding outward, so that a continuity test can be performed.

[Effect of idea]

As described above, according to the present invention, a coil spring 9 is arranged around the outer periphery of a sleeve 8 having a cylindrical shape, and an axial hole 10 is bored in a part of this sleeve 8.
A plunger contact pin 11 is slidably fitted into the opening 8c of the sleeve 8 with the contact portion protruding outward, and a locking pin 11 is inserted through the hole 10 and the plunger contact pin 11. Matching pin 12
is engaged with one end of the coil spring 9, and the conductive core 13 is stretched between the inner end 11a of the plunger contact pin 11 and the other end of the sleeve 8, so that the conductive core 13 does not buckle. Not only can cut-offs be prevented even when the device is in use, but also continuity tests can be performed stably over a long period of time, and assembly can be facilitated, leading to labor savings through mass production.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a contact probe according to the present invention, FIG. 2 is a front view showing a part of the above contact probe, FIG. 3 is a plan view of the same, and FIG.
The figure is an enlarged sectional view showing the main parts of the invention.
FIG. 5 is a diagram showing another embodiment of the present invention, and FIGS. 6 to 8 are sectional views of contact probes that have already been proposed. 8...Sleeve, 9...Coil spring, 10...
Strip hole, 11...plunger contact pin, 12...engaging pin, 13...conducting core, 14...socket.

Claims (1)

[Scope of utility model registration request] A coil spring is arranged around the outer periphery of a cylindrical sleeve having a pair of upper and lower flanges, a pair of axial holes are bored in a part of this sleeve, and a contact part is inserted into the opening of the sleeve. A plunger contact pin is slidably fitted in an outwardly protruding state, and an engaging pin provided through each of the holes and the plunger contact pin is engaged with one end of the coil spring. A contact probe characterized in that a conductive core is biased outward and is stretched between an inner end of the plunger contact pin and the other end of the sleeve by the elasticity of the coil spring.