Electrical connectors – Including or for use with coaxial cable
Reexamination Certificate
2002-11-05
2004-08-24
Patel, Tulsidas C. (Department: 2839)
Electrical connectors
Including or for use with coaxial cable
C439S620040
Reexamination Certificate
active
06780051
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a coaxial connector connected to a conductive panel, and more particularly, to a coaxial connector, a connecting part of which is to be connected to the conductive panel which is constituted of conductive material.
2. Related Art
A BNC connector is usually connected as a coaxial connector to be connected to a conductive panel.
In some BNC connectors, a signal ground of an external conductor is coupled directly to a ground frame of the conductive panel, to thereby ensure grounding. When a plurality of devices are interconnected by means of BNC connectors, such a grounding method enables formation of a ground loop by means of a potential difference among the devices. As a result, flow of an electric current arises among the devices.
In order to prevent formation of such a ground loop, there is described a capacitive-coupling connector, as disclosed in Japanese Patent No. 2578675.
In the capacitive-coupling connector, a capacitor is interposed between an external conductor and a conductive panel in order to connect them together. The capacitor enables electric discharge of electricity from the external conductor to the conductive panel so that the capacitive-coupling between the potential of the external conductor and the potential of the conductive panel may be made.
In the case of a BNC connector having a capacitor incorporated therein, a connection section (screws) must be constituted of an insulator so as to prevent direct connection between the external conductor and the conductive panel.
However, plastic is used as an insulative material for a connection section. Since plastic is a kind of dielectric material, an electromagnetic wave developed in the devices may radiate to the outside of the devices through a plastic member.
In this regard, when a coaxial cable is connected to a terminal on a conductive panel, a connection section of the connector is formed such that an external conductor of the connector, a plastic member (a dielectric substance), and a conductive panel are connected, in this order. Here, a plastic member (i.e., a dielectric substance) portion also serves as a screw. For this reason, the thickness of the plastic member (dielectric substance) portion cannot be made extremely thin. In order to connect the external conductor and the conductive panel to the connector while ensuring mutual isolation, a certain degree of thickness is required.
However, as the thickness of the plastic member (dielectric substance) increases, the distance between shield walls constituted of the external conductor and a conductive panel becomes greater, thereby failing to effectively shield an electromagnetic wave. Hence, a screw section of a conventional BNC connector having a certain thickness inevitably fails to prevent electromagnetic waves developed in a device from radiating to the outside of the device through the plastic member.
A clock frequency used in a device, which is mainly responsible for developing electromagnetic waves, is increasing year by year. Since the electromagnetic wave with a higher frequency can more easily pass through a dielectric substance due to the properties thereof, a leakage of the electromagnetic waves may become more.
In particular, a device having a plurality of connection ports radiates an electromagnetic wave to the outside of the device more as the number of ports is increased.
SUMMARY OF THE INVENTION
It is an object according to the present invention to provide a coaxial connector which lowers radiation of the electromagnetic wave to the outside of the device and is improved in electromagnetic compatibility (EMC). It is also an object to provide a manufacture method of thereof and a preventing method of electromagnetic wave leakage by using the coaxial connector.
According to the present invention, there may be provided a connector which has a connection part to be connected to a conductive panel made of a conductive material and a thin dielectric member formed for ensuring insulation between an external conductor and the conductive panel wherein the connector has a structure that the thin dielectric member (insulator), which may be a path of an electromagnetic wave, is sandwiched between the conductor and the conductive panel.
More specifically, the invention provides the followings.
(1) A coaxial connector having an elongated internal conductor, a cylindrical external conductor being coaxial with the internal conductor, and an insulation main body for fixing the internal conductor and the external conductor in an electrically-insulating manner,
wherein the insulation main body comprises a block part for fixing the internal conductor and the external conductor to a root part of the insulation main body with the internal conductor and the external conductor insulated from each other, and a cylindrical part for covering a portion of an outer periphery of the external conductor; and
wherein the cylindrical part of the insulation main body has a conductive member for shielding an electromagnetic wave.
According to the present invention, there is further provided a coaxial connector including:
an elongated internal conductor,
an external conductor, in which at least a portion of the internal conductor is inserted, and
an insulation main body fixing the external conductor and covering at least a portion of the external conductor;
the coaxial connector comprising:
a coaxial cylindrical dielectric member at least a portion of which is inserted between the internal and the external conductors;
wherein the insulation main body comprises a block part and a cylindrical part with both parts connected to each other substantially along the axis of the coaxial connector;
the block part securing the internal conductor and the cylindrical dielectric member via the external conductor;
the cylindrical part wrapping around and/or holding a portion of an outer periphery of the external conductor and being wrapped around and/or held on the outer periphery thereof by a conductive member so that the cylindrical part has such overlapping portion wrapping and being wrapped around.
According to the present invention, a conductive member for shielding (or blocking) passage of an electromagnetic wave is provided on an outer periphery of a cylindrical part of an insulation main body of a coaxial connector. And a connection portion of the coaxial connector has a structure having an external conductor, the cylindrical part (a dielectric member), and a conductive member connected in the order so that an electromagnetic wave (noise) that passes the dielectric member may be attenuated between shielding walls of the external conductor and the conductive member, thereby minimizing the leakage of a developed electromagnetic wave from the coaxial connector.
The conductive member, which may include a conductive flange as an example, also works as a screw which serves as a mount portion to a conductive panel. Since the screw is made of a conductive material such as metal, the strength of the screw is increased if compared to a plastic screw.
If it is needed to insulate the external conductor from the conductive panel, the cylindrical part should be made of insulating material because the cylindrical part is not insulated from the external conductor and because it serves as a mount portion to the conductive panel. However, the plastic screw may not have enough strength as a mounting portion. The thickness can be increased for the strength, but a thicker plastic mounting portion may cause leakage of an electromagnetic wave through the portion. Hence, a thinner plastic portion is more preferable.
According to the present invention, a cylindrical part (a dielectric member) is made thin and a mount part to a conductive panel is made of a conductive material. Although the cylindrical part (i.e., the insulation portion) is made thin, it secures the strength of the mount part by means of its mechanical property. The overlapping portion, for example, may include a portion having the cylindrical part (a dielect
J.S.T. Mfg. Co. Ltd.
Patel Tulsidas C.
Rader & Fishman & Grauer, PLLC
LandOfFree
Coaxial connector and manufacture thereof does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Coaxial connector and manufacture thereof, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coaxial connector and manufacture thereof will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3355582