US2257259A

US2257259A - High frequency communication cable

Info

Publication number: US2257259A
Application number: US237071A
Authority: US
Inventors: Inoue Bunzaemon
Original assignee: Sumitomo Electric Industries Ltd
Current assignee: Sumitomo Electric Industries Ltd
Priority date: 1937-11-02
Filing date: 1938-10-26
Publication date: 1941-09-30
Anticipated expiration: 1958-09-30

Description

Sept. 30, 1941. B. INOUE HIGH FREQUENCY COMMUNICATION CABLE Filed 001:. 26, 1938 FIG.1.

FIG.2.

INVENTOR ATTORNEY Patented Sept. 30, 1941 HIGH FREQUENCY COMMUNICATION CABLE Bunzaemon Inoue, Osaka, Japan, assignor to Sumitomo Denki Kogyo Kabusiki Kaisya,

Osaka, Japan Application October 26, 1938, Serial No. 237,071

- In Japan November 2, 1937 3 Claims.

This invention relates to high frequency communication cables, comprising one or more inner conductors insulated by and carried on individual spacers of cylindrical shape. The said cylindrical spacers consist of a plurality of associated semicircular or segmental circular cylinders with a notch or notches provided for the passage of the inner conductor or conductors. An outer conductor is mounted upon the said cylindrical spacers or, if balanced construction is required, the outer conductor is omitted.

With this particular construction of the spacer, the manufacturing process of a long co-axial cable can be greatly simplified. According to a known method of constructing coaxial cables, it is necessary to pass one end of the inner conductor through the spacers one by one. Moreover, all the spacers already fitted to the conductor should be shifted along the conductor whenever a new spacer comes to be mounted. According to this invention the conductor may be stretched out in a line and slowly moved. The two or more pieces forming each spacer may be placed about the conductor and coupled in place thereon. A cable of two or more inner conductors can be similarly constructed.

Cables manufactured in this manner are of high efiiciency both electrically and mechanically, possessing the following distinct features over co-axial cables of a known type. The cable of the present invention maintains more flexibility owing to a single wall in each of the spacers to hold the central conductor, sufl'ers small dielectrical loss because of comparatively small area of contact between the conductor and the spacer, and may contain an outer conductor if the spacers are mounted adjacent each other along the entire length of the cable, owing to the fact that a rigid support for such conductor is provided by the cylindrically uniform surfaces of the spacers.

This invention is particularly based on the prior application of the same inventor Ser. No. 195,145, filed March 10, 1938, and is an improvement based on subsequent research.

A more definite and detailed understanding about the construction and operation of the present invention will be had in conjunction with the accompanying drawing which represents tragmentally sectional views'of three slightly diiferent applications of the device, namely: Fig. 1 shows a cable of cylindrical spacers whose one distal end is open and the other end is closed with a wall, Fig. 2 shows a cable of cylindrical spacers whose both ends are open but with a wall fitted in the middle, Figs. 2A and 2B show CPI alternative construction for the arrangement of Fig. 2, and Fig. 3 shows a balanced multi-core cable with cylindrical spacers each having two symmetrical notches instead of one on its wall fitted in the middle for the passages of the paired conductors. In Figs. 1 and 2. l is a central conductor; 2 and 3 represent spacers; .4 and 5 are associated members of the said cylindrical spacer, made of plastic, fibrous or ceramic material; 6 is a wall fitted in a distal end indicated at I, while the other end indicated at 8 is open; 9 is a wall fitted in the middle of the spacer, the both ends in this case being kept open; in is a notch providing a passage for conductor; and l l is an outer conductor mounted upon the said spacers. In Fig. 3,1'n which a balanced type of high frequency communication cable is represented, l2 and i3 are conductors; 4 and 5 are semi-circular cylindrical spacers; 9 is a wall fitted in the middle of the spacer; i4 and I5 are notches for conductor" passages provided on the said wall; I6 is fiber tape wound around the said spacer; and IT is a lead sheath. When four inner conductors are to be used, four associated quadrant-circular pieces two of which are shown in Fig. 2A are adopted in composing a circular cylindrical spacer.

In actual appliance of this device many other contrivances must be taken into consideration, for example as shown in Fig. 213, a number of small perforations 20 are provided on the wall 9 for the purpose of better aridity, economy and less dielectrical loss, and notch ID of the wall is made irregular in shape in order to minimize the contact area of the conductor with the wall, or

' to provide a means by which the said associated semi-circular cylindrical members are prevented from sliding along the conductor while in coupling relation.

Manufactured after the specification of the present invention as aforesaid, that is, having a single wall fitted in a spacerthis is the main feature of the invention-and having its conductor or conductors passed through a passage I or passages on the walls of the spacers to keep them at an equal distance with respect to the spacers or in symmetrical positions with respect to each other, a cable will be very flexible and will have low dielectric loss owing to the facts that the contact area of the conductor or conductors with the insulator is small and the spacing of the inner conductor with respect to an outer conductor which may be provided is uniform all the way through. Due to the longitudinal cylindrical surfaces of the spacers, its outer conductor may be mounted with more facility.

It is to be understood that the embodiment of the invention herein disclosed is illustrative only and may be modified in many ways without departing from the scope and spirit of the invention limited solely by and in the appending claims.

What is claimed is:

l. A high frequency communication cable comprising at least one inner conductor and an outer conductor, said inner and outer conductors being separated and insulated by spacers oi substantially circular cylindrical shape, each of said spacers being composed of a plurality of associated circular cylindrical segments and each of said segments having a single wall segment on the inside thereoi provided with a notch, the wall segments mating to form a single wall extending across one portion of the spacer and the notches mating to form an aperture for the passage of the inner conductor.

2. A high frequency communication cable according to claim 1 wherein the said wall is perforated and said aperture in said wall is uneven so as to minimize the contact area of said conductor with said wall.

3. A high frequency communication cable comprising at least one inner conductor and an outer conductor, said inner and outer conductors being separated and insulated by spacers oi substantially circular cylindrical shape, each 0! said spacers being composed of a plurality of associated circular cylindrical segments and each of segments having a single wall segment on the inside and intermediate the ends thereof provided with a notch, the wall segments mating to form a single wall extending across one portion of the spacer and the notches mating to form an aperture for the passage of the. inner conductor.

B. INOUE.