JPS5931193B2 - FT type connector - Google Patents

Description

Detailed Description of the Invention This invention is based on JIS (-5410 (General Rules for High Frequency Coaxial Connectors)) for use in outdoor facilities for television joint reception, with a nominal impedance of 75Ω and a voltage of 350V (effective value).
This invention relates to an FT connector designed for a frequency of 250 MH2 or less.

The structure of a conventional FT type connector of this type will be explained with reference to FIGS. Insulators, 5 and 6 are O-rings provided inside and outside the second insulator 4, T is a center contact provided inside the connector body 1 so as to partially protrude, and 8 is a third insulator inside the connector body 1. , 9 is a flanged taper clamp, 10 is a clamp provided on the outside of the flanged taper clamp 9, 11 is a fastening fitting that is screwed into the connector main body 1, and 12 is a seal between the connector main body 1 and the fastening fitting 11.

ring, 13 is a tightening clamp provided in the tightening fitting 11;
Reference numeral 14 indicates a gasket for clamping the surface of the cable A, and reference numeral 15 indicates a washer interposed between the tightening clamp 13 and the gasket 14. However, in order to connect cable A to a device (not shown) using the FT type connector with the above structure,
First, the tightening fitting 11, gasket 14, washer 15, tightening clamp 13, and clamp 10 are sequentially inserted onto the outer surface of the cable A.

Next, the end of the cable A is terminal-treated using a tool as shown in the third diagram. That is, the inner conductor B is made to protrude beyond the insulator C1, the outer conductor D, and the outer sheath E, and the insulator C
and the outer conductor D to form a space F having a triangular cross section. Then, the flanged taper clamp 9 is fitted into the space F (see FIG. 4). Furthermore, the third insulator 8 is inserted into the internal conductor B of the cable A so as to come into contact with the flanged taper clamp 9. After inserting the taper clamp 9, the inner conductor receiving portion 7a of the center contact 7 is fitted into the tip of the inner conductor B of the cable A. After this fitting, the internal conductor B and the center contact 7 are connected by crimping from the outside of the fitting portion. After connecting the center contact 7, the center contact is connected to the first insulator 3, the second insulator 4 and the O
The rings 5 and 6 are respectively inserted into the built-in connector body 1 until the bulge of the center contact 7 contacts the step of the second insulator 4. Next, after inserting the clamp 10 into the connector body 1, when the tightening clamp 13 is tightened to the connector body 1, an expanded external conductor is formed between the flanged taper clamp 9 and the clamp 10 located on the outside of the clamp 9. D and the jacket E are sandwiched, and the cable A can be fixed to the connector main body 1. After fixing the cable A, the washer 15 and gasket 14 are moved, and the fastening fitting 11 is screwed into the connector body 11. This screwing is continued until the gasket 14 within the fastening fitting 11 contracts and tightly presses against the outer surface of the cable A. After both the connector body 1 and the fastening fitting 11 are fastened, the inside of the connector is watertightly sealed by the O-rings 2, 5, 6, 12 and the gasket 14. However, it has been found that when connecting using the conventional FT type connector described above, there are the following drawbacks. In other words, the one-flange taper clamp 9 can be precisely machined, but since the insulator C of the cable A is difficult to precisely extrude, the inner diameter of the flanged taper clamp 9 has a large dimensional error. The skin may also become thicker or thinner.

A gap is created between the insulator C and the external conductor D due to the difference in the inner diameter of the flanged taper clamp 9 and the outer diameter of the insulator C. In addition, the outer conductor D and the outer sheath E that have peeled off from the insulator C of the cable A are forcibly expanded outward in a tapered shape, and are held between the narrow tapered surface between the flanged taper clamp 9 and the clamp 10. This not only causes embrittlement and cracks at the peeled base of the external conductor D, but also causes a large load to be applied to the narrow tapered clamping surface between the flanged taper clamp 9 and the clamp 10. The combination of the taper structure of the clamp used to hold and fix cable A and the dimensional error of insulator C makes outer conductor D more likely to crack, resulting in disconnected grounding. This will cause electrical characteristics such as impedance and voltage standing wave ratio to go out of order. 2 Gasket 14 firmly compresses the outer surface of cable A, so when the insulator C of cable A is made of a soft material such as foamed polyethylene or ultra-high foamed polyethylene, the cable The outer surface will be significantly constricted compared to the nearby cable outer surface.

When the outer surface of the cable is greatly constricted by the gasket, electrical characteristics such as impedance and voltage standing wave ratio are impaired, resulting in problems with images. When connecting a cable to the three connectors, the parts that make up the connector are separated one by one, and moreover, the number of parts required is as many as nine.

If there are a large number of parts, there is a risk of the parts being lost or damaged during the connection process, or the connection process is extremely troublesome, so it is difficult for ordinary amateurs to perform the installation work. There were some inconveniences, such as the fact that it was not possible to do so, and that it was limited to specialists. This invention has been made to eliminate the above-mentioned drawbacks all at once, and its purpose is to remove the outer conductor and sheath at the end of the cable without causing any damage to the peeled base of the outer conductor of the cable when connecting the cable. It can be held securely and effectively, and even when sealing the outer surface of the cable, it can be completely sealed without adversely affecting the electrical characteristics of the cable, and it can be done quickly and easily, even by a layman, without damaging any parts when connecting the cable. An object of the present invention is to provide the general public with an FT type connector that can be easily worked on.

An embodiment of the present invention will be described below with reference to the drawings.

} The same reference numerals are given to parts having the same names as those shown in the conventional example. 1 is the connector body, and the device connection tool (
An O-ring 2 for sealing is attached to the base of the screw part 1a on the side that is screwed into the screw part (not shown), and an O-ring 2 for sealing is attached to the base of the screw part 1b that is screwed into the tightening fitting 11 (not shown), and the fitting 11 and the main body 1 are attached Each is provided with an O-ring 12 for sealing.

A columnar first insulator 3 having an insertion hole 3a for the center contact 7 is caulked to the tip inside the connector main body 1, and the center contact 7 comes into contact with the first insulator 3.
A columnar second insulator 4 having an insertion hole 4a is fitted therein. 5 and 6 indicate O-rings provided inside and outside the second insulator 4.

The inside of the connector main body 1 consists of three different hole diameters, the hole diameter 1d on the right side is slightly larger than the hole diameter 1c in the center part, and the step part 1f.
The hole diameter 1e on the left side is larger than the hole diameter 1c in the center. Reference numeral 11 denotes a cylindrical fastening fitting having a side surface having a fastening portion 11a on the outer surface, and a threaded portion 11b which is threadedly engaged with the threaded portion 1b of the connector main body 1 is formed at one end of the inner circumferential surface.

The other end of the fastening fitting 11 has a cable insertion hole 11c, and a vertical wall 11 is provided at a position adjacent to the cable insertion hole.
The threaded portion 1 has a diameter larger than that of the cable insertion hole 11c through d.
A clamp insertion hole 16 is formed which is smaller than the screw hole 1b and has a uniform thickness. Reference numeral 17 denotes a split cylindrical clamp that is loosely fitted into the clamp insertion hole 16;
A tapered surface 18 is formed by linearly cutting both ends of.

This split cylindrical clamp 17 has a split 19 in the axial or oblique direction so that it narrows uniformly toward the axis, and the inner wall of the clamp 17 has a continuous split 19 in order to increase frictional resistance. An uneven surface or a spiral thread 20 is formed. 21, 21 This is a cylindrical tightening clamp that is loosely fitted into the clamp insertion hole 16, and has a tapered surface 21a that is the same as the tapered surface 18 formed at both ends of the split cylindrical clamp 17.
, 21a', and both 17, 21, 211 are in pressure contact with each other at their tapered surfaces.

An annular ring 23 made of rubber or synthetic resin is fitted into an annular groove 22 formed on the inner wall surface of the non-pressure contact surface (non-tapered surface) of the tightening clamp 21, and a ring 23 made of rubber or synthetic resin is fitted between the annular groove 22 and the vertical wall surface 11d. , the annular ring 23 is pressed to prevent water from entering the clamping fitting 11 from the outer surface of the cable A. In order to prevent the pressing force on the outer surface of the cable A by the annular ring 23 from becoming too strong, the end surface 24 of the tightening clamp 21 is
The structure is such that the bolt contacts the vertical wall surface 11d of the fastening fitting 11, so that it will not be tightened any more strongly. In addition, the end surface 25 on the non-pressure contact surface (non-tapered surface) side of the tightening clamp 2' has a bulge 26 formed at the end of the connector body 1 when the connector body 1 and the clamping fitting 11 are screwed together. comes into contact with the end surface 27 of. 28 is an annular ring 23 inserted into the clamp insertion hole 16 of the fastening fitting 11 in order from the left side.
, a tightening clamp 21, a split cylindrical clamp 17, and a tightening clamp 21 (retaining members such as protrusions to keep the above-mentioned parts all together in the clamp insertion hole 16 when stored as shown in the figure). If the holding members are projections as in this example, a plurality of them (in this example, 4 pieces at 90-in intervals) are provided at the ends on the circumference of the clamp insertion hole 16.

A cylindrical ferrule 29 is housed in the clamp insertion hole 16 of the clamping fitting 11 and in a part of the connector body 1, and includes a cylindrical part 29a to be inserted between the insulator C and the external conductor D of the cable A, and It is composed of an annular flange 29b formed on the outer peripheral surface of one end of the cylindrical portion 29a, and a slitted cylindrical elastic piece 29c extending from the outer periphery of the flange 29b.

The entire length of the cylindrical ferrule 29 is formed to reach from the end surface (step part 1f) within the hole diameter 1e on the left side of the connector body 1 to near the annular ring 23. The slitted cylindrical elastic piece 29c has a center conductor insertion hole 8a for the cable A.
A column-shaped third insulator 8 having a diameter is fitted therein, and the end surface of the third insulator 8 is in contact with the surface of the stepped portion 1f in the connector main body 1. Then, in the center of the third insulator 8, a groove 8b is formed into which the end of the internal conductor receiving part 7a of the center contact 7 is fitted, and the center contact 7 is fixed in the groove 8b in advance. Alternatively, it may be inserted separately later. The outer peripheral surface of the annular collar portion 29b abuts against the inner wall surface of the hole diameter 1e on the left side of the connector main body 1. The length of the outer peripheral surface 29d of the cylindrical portion 29a is determined from the vicinity of the annular ring 23 to the annular collar portion 2.
The inner peripheral surface 29e of the cylindrical portion 29a has a length extending from the annular ring 23 to the third insulator 8. Since the present invention has the above-mentioned configuration, in putting it into practice, the terminal of the cable A is first processed as shown in FIG.

Next, the clamping fitting 11 containing the annular ring 23, the clamping clamps 21, 21' and the split cylindrical clamp 17 is inserted into the cable A. After the fastening fitting 11 is inserted, the cylindrical portion 29a of the cylindrical ferrule 29 is inserted between the insulator C and the external conductor D of the cable A. Since the third insulator 8 to which the center contact 7 is attached is fitted in advance to the cylindrical elastic piece 29c of the cylindrical ferrule 29, the tip of the inner conductor B of the cable A is inserted into the inner conductor receiving portion of the center contact 7. 7a and crimp it from the outside with a tool. After the center contact 7 is crimped, the center contact 7 is inserted into the connector body 1 until the bulge of the center contact contacts the second insulator 4. Thereafter, by simply tightening the fastening fitting 11 to the connector body 1, the interior of the connector is completely watertightly sealed by the O-rings and the annular rings. As can be seen from the above description, the present invention includes inserting the cylindrical portion 29a of the cylindrical ferrule 29 between the insulator C and the outer conductor D of the cable A, and tightly contacting the cylindrical portion 29a on the outer peripheral surface of the cylindrical portion 29a. A split cylindrical clamp 17 accommodates the located external conductor D and sheath E in the clamp insertion hole 16 of the clamping fitting 11, and the left and right clamps 21, 21' that press against the clamp 17 can cover a wide area. It can be securely clamped and fixed in a uniform state over the entire length.

Therefore, there is no need to widen the outer conductor D of cable A in a tapered shape from the surface of insulator C and insert a flanged taper clamp here, as in the conventional case.
Because it is sufficient to simply insert the cylindrical ferrule 29 into the insulator C regardless of the tolerance of There is no As a result, there is no change in the electrical properties of the cable, particularly the impedance and voltage standing wave ratio, which provides an excellent effect of being free from troubles in the image. In addition, the outer surface of the cable inserted into the cable insertion hole of the clamping fitting has an annular shape interposed between the vertical wall surface of the clamp insertion hole formed in the clamping fitting and the tightening clamp in the clamp insertion hole. Since the ring is used for pressure contact, even if both the connector body and the fastening fitting are tightly tightened, the elastic force exerted by the annular ring on the outer surface of the cable will not exceed a certain limit. .

Therefore, the outer surface of the cable is firmly clamped by the gasket loaded in the clamping fitting, and is free from major deformation, which is the case with cables with soft insulation. Even if the cable is made of 100% polyurethane, it has the excellent effect of being able to effectively seal the cable in a watertight state without deforming the outer surface of the cable. A further advantage of this invention is that the annular ring, tightening clamp, and split cylindrical clamp are all housed in the clamp insertion hole formed in the tightening fitting, and these parts are prevented from protruding outside. Since a holding member such as a protrusion is provided at the end of the clamp insertion hole, there is no need to take out each of these parts from the clamping fitting and attach them to the cable when connecting the cable, making it easy to tighten these parts. Simply insert the cable into the clamping fitting while it is still housed in the fitting.

Therefore, since there are as many as nine parts when connecting a conventional cable, and each part is in a separate state, the connection work is either very troublesome or it is easy to lose parts during the connection work. The present invention eliminates the risk of causing damage, and the number of parts when connecting the present invention is only 3, less than half that of the conventional method, and it is expected to greatly improve work efficiency. It can be easily installed even by an amateur, and can be said to have extremely high utility value in this type of field.

[Brief explanation of the drawing]

Figure 1 is a half-cut sectional view showing a conventional FT type connector, Figure 2
The figure is a side view, Figure 3 is a half-cut sectional view showing the cable terminal processing, and Figure 4 is a sectional view showing the cable connection state.
FIG. 5 is a half-cut sectional view showing one embodiment of the present invention, FIG. 6 is a side view thereof, and FIG. 7 is a half-cut sectional view showing the terminal treatment of the cable. 1... Connector body, 7... Center contact, 11
... Tightening metal fitting, 11d... Vertical wall surface, 16... Clamp inserter Ll7... Split cylindrical clamp, 18...
・Taper' surface, 21, 21... Tightening clamp, 23・
... Annular ring, 28 ... Pressing member, 29 ... Cylindrical ferrule.

Claims (1)

[Claims] 1 Inside the connector body, there are three different hole diameters: a hole diameter on the right side that is slightly larger than the hole diameter in the center part through the step part, and a hole diameter on the left side that is expanded larger than the hole diameter in the center part through the step part, A column-shaped first insulator whose tip is caulked into the hole on the right side of the connector body, and a column-shaped insulator which is attached inside and outside and abuts the first insulator via an O-ring and has an insertion hole for a center contact. The left hole in the connector body has a cylindrical part to be inserted between the cable insulator and the outer conductor, and a second insulator formed on the outer peripheral surface of one end of the cylindrical part. Of the cylindrical ferrule that is composed of an annular flange and a slitted cylindrical elastic piece extending from the outer periphery of the annular flange, the slitted cylindrical elastic piece is tightly fitted onto the outer periphery of the annular flange. The slitted cylindrical elastic piece is inserted until the end of the connector body contacts the stepped part of the hole on the left side of the connector body, and the end of the center conductor insertion hole of the cable and the inner conductor receiving part of the center contact are inserted into the slitted cylindrical elastic piece. A third columnar insulator having a groove formed in the center thereof to be fitted is fitted therein, and a threaded portion to be screwed into the outer circumferential surface of the connector body is formed at one end of the inner circumferential surface. The other end has a cable insertion hole, which is located adjacent to the cable insertion hole through the vertical wall and has a diameter larger than the cable insertion hole and smaller than the hole diameter of the threaded part on the inner circumferential surface of the fastening fitting. , and a split cylindrical clamp formed with a clamp insertion hole of uniform thickness, in which both ends are notched linearly to form a tapered surface, and a tapered surface at both ends of the split cylindrical clamp. Left and right tightening clamps are provided in a loosely fitted manner to fit and press against each other, and an annular ring is inserted between the annular notch of the left tightening clamp and the clamp insertion hole to seal the outer peripheral surface of the cable between the vertical walls. The annular ring, the left and right tightening clamps, and the split cylindrical clamp are inserted into the clamps at the same time. A presser member is provided at the end of the clamp insertion hole so as to be enclosed in the hole, and a cylindrical portion of the cylindrical ferrule longer than the clamp is further inserted into the split cylindrical clamp with a portion thereof protruding. The FT type connector is characterized by the