JPH0343674Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] This invention relates to a transmission duct end device used in a trolley duct or the like for transmitting video signals.

[Background technology]

BACKGROUND ART Conventionally, a system in which power is supplied from a trolley duct to mobile equipment such as a trolley or a crane has been used in factories and the like. By applying this system, we considered making it possible for a television camera for monitoring production lines to run along the trolley duct, and transmitting video signals through the trolley duct.

When transmitting high-frequency waves used for carrying video signals, etc., it is necessary to connect a terminating resistor for impedance matching to the end of the conductor in the duct in order to prevent reflection at the end of the conductor. However, in the trolley duct, vibrations are generated due to the running of the trolley, etc.
If the terminating resistor is simply connected with a lead wire, the lead wire may break due to vibration. Another problem is that it takes time and effort to draw out and connect the lead wires.

[Purpose of invention]

This invention provides a transmission duct end device that allows impedance matching at the end of the duct, prevents the wiring path of the terminating resistor from being disconnected due to duct vibration, and makes it easy to install the terminating resistor. The purpose is to

[Disclosure of invention]

The transmission duct end device of this invention includes an end box installed at the end of a duct containing a pair of conductors for signal transmission, and a terminating resistor housed within the end box for impedance matching of the duct. The device includes a printed wiring board, and a pair of conductor joints each connected to the terminal ends of the pair of conductors to fix the printed wiring board and connected to the terminating resistor via a conductor pattern.

According to the configuration of this invention, since the terminating resistor is connected to the conductor of the duct, impedance matching is obtained. Since the terminating resistor is mounted on the printed wiring board, it is resistant to vibration and is less likely to break due to vibrations occurring in the duct. Furthermore, since a printed wiring board is used and the conductor in the duct is electrically and mechanically connected to the printed wiring board using a conductor joint, the workability is better than when connecting by drawing out lead wires.

Embodiment An embodiment of this invention will be described based on FIGS. 1 to 3. This transmission duct end device includes an end box 3 installed at the end of a duct 2 that accommodates a pair of conductors 1 for signal transmission, and a terminating resistor housed in the end box 3 and having a value equivalent to the impedance of the duct 2. 4 mounted thereon, and a pair of conductor joints 6 each connected to the terminal ends of a pair of conductors 1 to fix the printed wiring board 5 and connected to a terminating resistor 4 via a conductor pattern 5a. It is something.

Duct 2 is a trolley duct,
The duct body 2' is comprised of a downwardly extending lip groove-shaped duct body 2' shown in FIG. 2, and a conductor 1 provided on the lower surface of the web with insulators 8 and 9 interposed therebetween. 2a is an opening.
The duct body 2' is made of conductive material such as a steel plate,
Has a shielding effect. A current collecting trolley 10 runs on the lip portion 2b of the duct body 2'. 1
0a is a wheel of the trolley 10, and 10b is a current collector. The collector 10b is connected to a television camera or the like by wiring.

As shown in FIG. 1, the end box 3 has an open top surface and a duct connection surface, and is disposed against the terminal end of the duct body 2'. The end box 3 is attached using a pair of side lids 11 (FIG. 2) and an upper lid 12, each having a length spanning the entire length of the end box 3 and the notch 2c of the duct body 2. The side cover 11 covers the curled portion 2d of the duct body 2'.
Then, the lower end is hooked onto an engaging portion (not shown) on the lower surface of the end box 3, and the upper end is placed over the upper side edges of the end box 3 and the duct body 2'. The upper lid 12 is placed on top of this.

As shown in FIG. 3, the conductor joint 6 has a rectangular cylindrical shape, and the conductor 1 is inserted into the conductor fixing screw 13.
Tighten and secure. A terminal screw 14 (FIG. 1) is further screwed into the conductor joint 6, and the terminal screw 14 is inserted into a hole in the printed wiring board 5 to fix the printed wiring board 5 and the conductor joint 6 to each other. The conductor pattern 5 a connected to the terminating resistor 4 of the printed wiring board 5 is in direct contact with the conductor joint 6 or is connected to the conductor joint 6 via the terminal screw 14 .

According to this configuration, since the terminating resistor 4 is connected to the conductor 1 of the duct 2, impedance matching can be achieved. Since the terminating resistor 4 is mounted on the printed wiring board 5, it is resistant to vibrations and is unlikely to be disconnected even by vibrations generated in the duct 2. Also, using the printed wiring board 5, the conductor 1 in the duct 2 is connected to the conductor joint 6.
Since the wiring board 5 and the printed wiring board 5 are electrically and mechanically connected, the workability is better than when connecting by pulling out lead wires.

Although the above embodiment has been described with reference to the case where the duct 2 is for a trolley, the duct 2 may be configured to fix a signal transmission device at any position in the longitudinal direction. Further, a plurality of pairs of conductors 1 may be provided within the duct body 2'.

[Effect of idea]

In the transmission duct end device of this invention, since the terminating resistor is connected to the conductor of the duct, impedance matching can be obtained. Since the terminating resistor is mounted on the printed wiring board, it is resistant to vibration and is less likely to break due to vibration generated in the duct. In addition, since a printed wiring board is used and the conductor in the duct is electrically and mechanically connected to the printed wiring board using a conductor joint, work efficiency is improved compared to connecting by pulling out lead wires. .

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of this invention, FIG. 2 is a sectional view of the duct, and FIG. 3 is a sectional view of the conductor joint. 1... Conductor, 2... Duct, 3... End box, 4... Terminating resistor, 5... Printed wiring board, 6... Conductor joint.

Claims (1)

[Scope of utility model registration request] an end box installed at the end of a duct containing a pair of conductors for signal transmission; a printed wiring board housed within the end box and mounted with a terminating resistor for impedance matching of the duct;
A transmission duct end device comprising a pair of conductor joints each connected to the terminal ends of the pair of conductors to fix the printed wiring board and connected to the terminating resistor via a conductor pattern.