JPH02142076A - Coaxial monitor jack - Google Patents

Abstract

PURPOSE:To prevent the electrostatic obstacle in the measuring by providing a contact C which is arranged to contact before a contact G of the outer conductor of a coaxial cord for measuring to insert contacts to a contact B for outer conductor, but not to contact in a regular setting condition, and to connect to the earth. CONSTITUTION:While a contact B2 for the outer conductor is provided coaxially to a contact A1 for the center conductor, a contact C3 is arranged in front of the contact B2 not linking to the contact B2 so as to contact before a contact G91 of the outer conductor of a coaxial cord 9 for measuring contacts to the contact B2, but not to contact in the regular setting condition, and connected to the earth. When the cord 9 is inserted to a coaxial jack 5, the gearing and connecting condition is made after the contact piece of the contact C3 is contacted to the contact G91 necessarily. Even though there occurs an electrostatic charge to the cord 9 by this contact, it is discharged to the frame earthing through a terminal lead 33, and no discharge to the circuit earthing through the contact B2 occurs. Consequently, the electrostatic obstacle in the measuring can be prevented.

Description

[Detailed Description of the Invention] [Summary] Regarding a coaxial monitor jack provided to check the operating status of a device, the purpose of this invention is to provide a coaxial monitor jack that prevents electrostatic interference during measurement, and has a contact A for the center conductor. Contact B for external conductor
In addition, it is arranged so that it has no conduction with contact B, contacts G of the outer conductor of the inserted coaxial cord for measurement come into contact before contact B, and are not in contact when properly fitted. and a contact C for ground connection.

[Industrial application field]

The present invention relates to a coaxial monitor jack provided for checking the operating status of a device.

The device is equipped with a monitor jack at a predetermined location, which is connected directly to the measuring device by modifying the circuit so that the device can be checked without any effect while it is in operation without stopping the device.

On the other hand, in recent years, the parts used in modern devices have become extremely small, power consumption has been reduced, and they have become more compact and high-performance, but on the other hand, their resistance to external physical interference is gradually weakening. There is a need to strengthen these measures more than ever before.

[Conventional technology]

An example of a decrease in device withstand strength is withstand voltage.

By reducing the operating voltage and current of semiconductors,
Other parts are also used with reduced withstand voltage, and naturally the withstand strength against abnormal voltage from the outside will be relatively reduced.

Specifically, external static electricity is discharged into equipment, causing malfunctions and component damage, and the extent of this is becoming smaller and smaller, making it necessary to strengthen countermeasures against static electricity. There is.

Currently, as a countermeasure against static electricity, emphasis is placed on preventing the generation of static electricity.
■Exams, educational guidance for maintenance personnel, etc. are becoming widespread.

However, countermeasures such as covering the surface of the device with a grounded metal cover are being taken.

FIG. 4 shows how a conventional coaxial monitor jack is installed.

In the coaxial monitor jack 55, an outer conductor 75 including a contact B25 forms a cylindrical outer shape with a stepped portion, and a threaded portion provided on the outer periphery is passed through a hole in an L-shaped fitting 66 and tightened with a ring nut. This metal fitting 66 is fixed to the printed wiring board 6 with screws, and is electrically unconnected to prevent the external conductor 75 from being incompletely grounded at multiple points in the middle of the circuit and affecting the characteristics. In this state, the coaxial cord 95 wired to the coaxial monitor jack 55 is extended as is and connected to the signal ground of the printed wiring connected to the printed wiring board 6.

However, if the external conductor is charged with static electricity from the contact G91 of the coaxial cord 9 for measurement, the external conductor 75 is charged from the contact B25 of the coaxial monitor jack 55 when connecting
and is further discharged through the coaxial cord 95 of the wiring to the circuit ground of the printed wiring.

■ This discharge to the circuit ground may cause fluctuations in the ground potential, resulting in circuit malfunction.

There was a problem.

In view of these problems, the present invention aims to provide a coaxial monitor jack that prevents electrostatic interference during measurement.

The above problem is that, as shown in Fig. 1, in addition to the contact A1 for the center conductor and the contact B2 for the outer conductor, the contact B2 is not electrically conductive, and the outer conductor of the coaxial cord 9 for measurement that is being inserted is not electrically connected to the contact B2. This problem is solved by the coaxial monitor jack of the present invention, which is provided with a contact C3 which is disposed so that the contact G91 contacts the contact B2 before contacting the contact B2 and is not in contact in the properly fitted state, and is connected to the ground.

[For production]

That is, the static electricity of the coaxial cable for measurement comes into contact with the contact C before connection, and can be discharged without going through circuit grounding, which serves the purpose.

Fig. 1(a) shows the principle of the present invention (inserted state), and Fig. 1(b) shows the principle of the present invention (inserted state).
) shows the same (mated connection state).

To illustrate and explain the coaxial monitor jack 5 of the present invention in cross section, as shown in FIG. 1, a contact B2 for an outer conductor is provided coaxially with a contact AI for a center conductor, and a contact C3 is provided at the front of the contact B2. It is possible to install it insulated, for example, as shown in the figure, by molding the outside with insulation mold and installing it integrally.

A coaxial cord 95 wired from the printed wiring is connected at the rear of contacts AI and B2, and the outer conductor 76 is ungrounded at the coaxial monitor jack 5.

Further, as shown in the figure, for example, the contact C3 has a plurality of spring contact pieces protruding in the direction of the central axis arranged on the inner wall of a coaxial circle, and is equipped with a terminal lead 33 for external connection, and is connected to the printed wiring board 6. The terminal board 33 is connected to a printed wire that connects to a frame ground of the structure separate from the circuit ground.

Thus, the measurement coaxial cord 9 is connected to the coaxial monitor jack 5.
is inserted, the contact piece of the contact C3 is sure to come into contact with the contact G91 of the outer conductor at the tip of the measuring coaxial cord 9, as shown in FIG. As shown in 1)), the mating connection state is established.

Due to this contact, even if the measuring coaxial cord 9 is charged with static electricity, it will be discharged to the frame ground, and will not be discharged to the circuit ground through the contact B2.

In this way, it is possible to provide a coaxial monitor jack that prevents electrostatic interference during measurement.

[Example] The gist of the present invention will be specifically explained below with reference to Examples shown in the drawings. The same reference numerals indicate the same objects throughout the plan, and FIG. 2 is a block diagram of one embodiment of the present invention, and FIG. 3 is a perspective view of another embodiment of the present invention.

The coaxial monitor jack 5L52 of this embodiment has a contact B2 for the outer conductor coaxially with the contact 1-AI for the center conductor, is plastic molded to have a rectangular shape, and the contact B2 is insulated on the printed wiring board 6. The measuring coaxial cord 9 is inserted from the front and connected to contacts A1 and B2, and the coaxial cord 95 is routed at the rear and wired to a predetermined position on the printed wiring board 6. Electrostatic discharge contacts C31 and 32 are provided in front of the contact B2 and insulated from the contact B2, and their configurations are different.

In the coaxial monitor jack 51 of one embodiment shown in FIG. 2, the front part 56 and the insertion guide part 57 are covered with a plating layer to form the contact C31.

A terminal lead 33 soldered to the front part 56 is led out, and when attached to the printed wiring board 6, is connected to a printed wiring of the frame ground.

Thus, when the measuring coaxial cord 9 is inserted in the hand, the contact G91 of the external conductor with the protruding tip
first touches the contact C31, and if there is any charge, it is discharged, and then the contact B2 and the contact A1 are
Contact is made in this order to reach a connected state.

Moreover, a coaxial monitor jack 5 of another embodiment shown in FIG.
In No. 2, a circular brush 58 made of conductive filamentous fibers is provided in the insertion opening to constitute a contact C32, which is led out by a terminal lead 33 and connected to the frame ground of the printed wiring.

When inserting the measurement coaxial cord 9, contact G9 at the tip
1 first touches the contactor 1-C32, and if there is a charge, it is discharged, and the process progresses further to reach a connected state. In this process, the conductive brush of the circular brush 58 is pushed and bent, but the contactor 1-82 are in a non-contact relationship (length, position) to prevent electrical charge from flowing into the signal grounding circuit through contact B2.

In the above embodiment, the contact 1-C31 is made of a plating layer, but it may be made of a thin copper plate or the like and molded into the same shape or petal shape.Also, the circular brush 58 of the contact C32 can be made of a conductive elastic thin wire or strip. A configuration in which they are arranged in a circumferential manner may also be used.

〔Effect of the invention〕

As described above, the present invention provides a coaxial monitor jack that prevents electrostatic interference during measurement, and is capable of responding to the increasing functionality of devices in the future, which is highly effective.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the principle of the present invention, Fig. 2 is a configuration diagram of an embodiment of the invention, Fig. 3 is a perspective view of another embodiment of the invention, and Fig. 4 is an example of a conventional coaxial monitor jack. The installation is in condition. In the figure, ■, 15 is contact A, 2.25 is contact B1
3.31.32 is contact C1 5,5L52.55 is coaxial monitor jack, 6 is printed wiring board, 75.76 is external conductor, 9 is coaxial cord for measurement, 33 is terminal lead, 56 is front part, 5
7 is an insertion guide portion, 58 is a circular brush, 66 is a metal fitting, 91 is a wiring contact G, and 95 is a coaxial cord. 50 72-year-old (OL) six-six-year-old, be *, invention of the welfare of $ 1 mouth-end of the mouth - moving frame J's purchase relation 2 52 rotation axis mo; tagile, 7 no.

Claims (1)

[Claims] In addition to the contact A (1) for the center conductor and the contact B (2) for the outer conductor, the contact B (2) is non-conductive and is connected to the inserted measuring coaxial cord ( 9) Outer conductor contact G (91)
A coaxial monitor jack comprising a contact C(3) which contacts the contact B(2) before contacting the contact B(2), is disposed so as to be non-contacting in a properly fitted state, and is grounded.