JP2000065271A - Terminal holder of flexible tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize and provide a terminal holder of flexible tube composed of two parts of a simple structure which can be mass produced by the injection molding and the like of a plastic, can be assembled without using a tool, and can fix the jacket or the like of an optical fiber code to a connection partner part with a good reliability. SOLUTION: An inner tube 1 having a convex 5 and a concave 6 on the outer periphery is provided to a connecting partner part such as a connector 2. A fastener 4 having a convex 7 is assembled to the inner surface of a tube receiving hole 3, a flexible tube such as a jacket (c) is provided and held between the inner tube 1, and the fastener 4 pressed in and fitted to the outer side of the inner tube 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible tube terminal holder which enables a flexible tube to be firmly connected to a connection partner without a tool. This holder is particularly suitable for use in connecting an end of a jacket (a jacket made of a flexible tube) such as an optical fiber cord or a coaxial cord to a connector or the like.

[0002]

2. Description of the Related Art For example, when connecting an optical fiber cord to an optical connector, a holding metal fitting is provided in a housing of the connector.
It is common practice to hold the optical fiber cord drawn into the connector housing by caulking or tightening the screw with a holding metal fitting, but this method requires that the holding metal fitting be built into the housing. Yes, it degrades connector productivity. When connecting, a tool for caulking or screwing is required. Depending on the degree of tightening of the metal fittings, there is a concern that the optical fiber in the cord may be broken. Since the cord simply holds the cord from the outside of the jacket, the reliability of fixing the jacket is insufficient. There is a problem.

On the other hand, among known pipe joints, there is one shown in FIG. This pipe joint is disclosed in JP-A-10-110870, in which an inner cylinder 22 provided on a main body 21 is inserted into a pipe 23 to be connected, and a cap nut (cover) 24 is attached to the main body 21. , And the cap sleeve 24 is contracted by the cap nut 24 so that the protrusion 2 on the inner surface of the sleeve is
The tube 23 is fixed on the inner cylinder 22 by biting 6 into the outer periphery of the tube 23.

This pipe joint can be used for connecting an optical fiber cord. Sleeve 2 for retaining inner cylinder 22
5 and extend the optical fiber inside the cord to the inner cylinder 2
When the jacket of the optical fiber cord is inserted between the extended inner cylinder 22 and the retaining sleeve 25, the optical fiber cord is connected to the main body 21 without applying a clamping force to the optical fiber. Can be.

[0005]

The pipe joint shown in FIG. 7 has an advantage that an optical fiber cord or a coaxial cord can be connected to the main body 21 without applying any tightening force to a core such as an optical fiber. However, on the other hand, the number of parts is large and assembly is complicated. Many parts that require cutting are included, and the manufacturing cost is high. Because of the screw fitting structure, it is conceivable to forget to attach the locking pin 27 (the possibility is not low at all). In this case, there is a concern that the cap nut 24 is loosened due to vibration or the like and the joint is disassembled after assembly. There is. If the cap nut is manually tightened, a large pull-out strength cannot be obtained, so an operation tool (wrench, spanner, etc.) is required, and simple connection cannot be performed. It has disadvantages such as.

Therefore, the present invention is composed of two parts having a simple structure which can be mass-produced by injection molding of plastics or the like, can be assembled without tools, and can reliably fix an optical fiber cord jacket or the like to a connection partner part. It is an object to realize and provide a terminal holder for a flexible tube.

[0007]

In order to solve the above-mentioned problems, the present invention comprises a mating part for connecting a flexible tube having an inner cylinder protruding to the outside and a stopper having a tube receiving hole. Forming a convex portion on the outer peripheral portion of the distal end of the inner cylinder, a concave portion at the middle portion of the longitudinal direction, forming a convex portion on the inner surface of the inner cylinder receiving hole of the stopper directly above the concave portion in a state where the stopper is attached; A flexible tube terminal holder in which the connection end side of a flexible tube is fitted to the outside of the inner cylinder, and the stopper is further fitted to the outside thereof so that the tube is sandwiched between the inner cylinder and the stopper. I will provide a.

[0008] It is more preferable that such a holder has the following configurations (a) to (e).

(A) The outer diameter of the tube fitting portion (the portion where the tube fits) of the inner cylinder is the same as or smaller than the inner diameter of the flexible tube, and the inner diameter of the tube receiving hole of the stopper is the same as that of the tube. The same or larger than the outer diameter of (B) The inner cylinder is formed integrally with the connection partner component, and a projection is provided on one of the mutual abutting surfaces of the stopper and the connection partner component, and a concave portion on which the projection fits is provided on the other. (C) The outer diameter of the proximal end of the inner cylinder is made equal to or larger than the outer diameter of the flexible tube, and the inner cylinder is vertically divided into two at the front side of the large diameter portion. Is provided. (D) A plurality of spiral cam grooves, one end of which is opened at the outlet of the tube receiving hole, are provided on the inner surface of a portion of the tube receiving hole for receiving the large diameter portion of the inner cylinder at a constant pitch in the circumferential direction. A cam follower which is slidably fitted in each cam groove is provided on the outer periphery on the distal end side of the stopper, and furthermore, the stoppers and the mating surfaces of the mating parts are fitted to each other at the end points where the inner cylinder is inserted into the stoppers. Two sets of matching projections and recesses are provided symmetrically. (E) The surface of the projection on the outer periphery of the inner cylinder on the tip side of the inner cylinder is a downward slope, and the surface of the projection on the inner surface of the tube receiving hole on the entrance side of the reception hole is a slope inclined in the opposite direction to the slope. Also,
When a hole in the inner cylinder is penetrated inside the mating part and a linear body such as an optical fiber covered and protected by a flexible tube can be pulled into the inside of the mating part from the hole in the inner cylinder, the inside becomes It can be used to connect optical fiber cords with core wires.
The holder used to connect optical fiber cords, etc.
It is preferable to provide a curved surface at the entrance of the hole of the inner cylinder and at the entrance of the tube receiving hole of the stopper to remove the edge of the hole and increase the diameter of the hole toward the entrance.

[0010]

In the holder according to the present invention, the structure of the two components, which are the constituent elements, is simple, and the two components can be formed by injection molding of plastic or the like which is excellent in mass productivity, thereby achieving cost reduction.

Further, after the inner cylinder is inserted into the tube, a stopper previously fitted on the tube is press-fitted to the outside of the inner cylinder to complete the assembling, so that the work can be performed without tools and the working efficiency is improved. improves.

Further, since the convex portion and the concave portion are provided on the inner cylinder and the convex portion is provided on the inner surface of the tube receiving hole, the tube is meandered and sandwiched. .

In the case of adding the above-mentioned configuration (a), the protrusion on the inner surface of the tube receiving hole is engaged with the protrusion on the inner cylinder, the stopper is securely prevented from coming off, and the holder is inadvertent. There is no decomposition.

Further, in the case where the stopper and the mating part are provided with a projection and a concave part and the two are fitted together, the stopper is prevented from rotating, and the effect of preventing disassembly is further enhanced.

Further, when the tip of the inner cylinder is divided into two parts, the diameter of the inner cylinder is reduced at the time of press-fitting of the stopper, and the effect of facilitating press-fitting can be obtained. In the case where the convex part on the outer circumference of the inner cylinder and the convex part on the inner surface of the tube receiving hole are provided with a slope, the guide part is guided by the slope at the time of attaching and detaching the stopper, so that the convex part on the side of the stopper makes it easy Being able to get over it makes it easier to install and remove the fasteners.

A spiral cam groove is provided on the inner surface of the tube receiving hole, and the cam follower on the inner cylinder is engaged with the cam groove. As a result, a propulsive force for press-fitting the stopper is generated, so that the stopper can be easily mounted manually.

In addition, if a curved surface for increasing the hole diameter toward the entrance is provided at the entrance of the inner cylinder and the entrance of the tube receiving hole, the striated body such as an optical fiber passing through the inner cylinder swings laterally. Even if it hits the edge of the hole, a tight bending force is not applied to the contact point, so that the striated body at the exit portion from the hole hardly breaks.

[0018]

FIG. 1 shows an embodiment of a holder according to the present invention. The holder shown in the figure is an example in which the optical fiber cord A is connected to the optical connector 2. As shown in FIG. 2, the optical fiber cord A is an optical fiber a (core wire).
Is wrapped with a reinforcing fiber b made of an aromatic resin tensile strength fiber or the like, and the outside thereof is covered with a jacket c made of a vinyl tube or the like.

The holder shown in FIG. 1 comprises an optical connector 2 having an inner tube 1 and a stopper 4 having a tube receiving hole 3. A convex portion 5 (in the figure, an annular convex portion) is provided on the outer periphery of the distal end of the inner cylinder 1, and a concave portion 6 (in the figure, an annular groove) is provided in the longitudinal middle portion of the inner cylinder 1.

The inner surface of the tube receiving hole 3 has
A projection 7 is provided directly above the recess 6 when the stopper 4 is attached. When the tube receiving hole 3 and the inner cylinder 1 are concentric, the radial gap g generated between the projections 5 and 7 is set smaller than the thickness of the jacket c. The outer diameter d of the tube fitting portion of the inner cylinder 1 is equal to or smaller than the inner diameter of the jacket c, and the inner diameter d ₁ of the tube receiving hole 3 is equal to or smaller than the outer diameter of the jacket c. It has been enlarged.

In this holder, the inner cylinder 1 is inserted into the inside of the jacket c, and the stopper 4 is pressed into the outer side thereof so that the reinforcing fibers b
And the jacket c are sandwiched between the inner cylinder 1 and the stopper 4. In this case, the reinforcing fiber b and the jacket c are caught by the projections 5 and 7 and cannot be easily pulled out. In particular, the provision of the concave portion 6 and the convex portion 7 causes the jacket c to meander in a complicated manner between the inner cylinder and the stopper 4, so that the pull-out strength is enhanced and stable retaining is performed.

The optical fiber a passes through the inside of the inner cylinder 1 and is drawn into the housing of the connector 2. Therefore, the optical fiber cord A
Is not affected at all by the stress of retaining.

In this case, since the holding member has a high pull-out strength, the projection 7 goes over the projection 5 while compressing the jacket c when the stopper 4 is fitted. In some cases, the stress is high and the press-fitting by human power becomes difficult. Therefore, in such a case, structures and elements as shown in FIGS. 3 to 5 are added. The additional elements are listed below.

(1) Surface 5a of projection 5 in front of inner cylinder insertion direction
Is a slope of the front going down which is easy to get over the convex portion 7. (2) A slit 8 is provided in the tube fitting portion of the inner cylinder 1 so as to divide the inner cylinder into two vertically so that the inner cylinder 1 is reduced in diameter when the projection 7 passes over the projection 5. (3) A large-diameter portion 1a having the same diameter as or larger than the outer diameter of the jacket c (FIG. 1) is provided on the base end side of the inner cylinder 1, and a spiral is formed on the inner surface of the large-diameter portion receiving portion 3a of the tube receiving hole 3. Cam groove 9 (FIGS. 3 and 6 show the developed groove).
Is provided. A cam follower 10 is provided on the outer periphery of the distal end of the large diameter portion 1a so as to be slidably fitted into the cam groove 9. In this way, the stopper 4 is fitted while being rotated, thereby generating an axial thrust as a press input to the engaging portion between the cam groove 9 and the cam follower 10. If a plurality of pairs of the cam grooves 9 and the cam followers 10 are provided at a constant pitch in the circumferential direction, axial thrust can be generated with good balance. By performing the above-described contrivance, easy assembly by human power becomes possible.

Next, in particular, when the configuration (3) is adopted, there is a possibility that the stopper 4 will loosen naturally. Therefore, as shown in FIGS.
The recess 11 is provided symmetrically on the end surface of the inner cylinder 1, and the stopper 4 comes to a position corresponding to the recess 11 at the insertion end point of the inner cylinder 1.
1 is provided with a projection 12 which fits. The recess 11 and the projection 12
The rotation of the stopper 4 due to an unexpected stress is prevented by the engagement of the stopper, and the reliability of preventing the holder from being disassembled is increased.

As shown in FIGS. 1, 3, 4, and 6,
If the surface 7a of the convex portion 7 on the entrance side of the receiving hole is inclined in the opposite direction to the inclined surface 5a, the convex portion 7 can easily get over the convex portion 5 even when the stopper 4 is removed.

Also, as shown in FIG.
When the core wire is passed through the inside of the inner tube 1 and drawn into the inside of a connector or the like, as shown in FIG. 6, the edges of the hole ends of the hole of the inner tube 1 and the entrance of the tube receiving hole 3 are removed. When the curved surfaces 1b and 3b are provided so as to increase the hole diameter toward the inlet side, even if the core wire passed through the inner cylinder 1 swings in the direction perpendicular to the axis,
A local bending stress is not applied to the edge of the hole, and it is possible to avoid a break in the core wire and a damage to the jacket at the outlet from the hole due to the local bending.

[0028]

As described above, in the tube terminal holding device of the present invention, an inner cylinder having a convex portion on the outer periphery is provided on the connection partner part, the inner cylinder is inserted into the end of the tube, and the inner cylinder is inserted outside the tube. A stopper provided on the inner surface of the tube receiving hole with a convex part that is retained by the convex part is press-fitted to hold the tube end, so that the component parts are simple, mass production by injection molding or the like is possible, and cost reduction can be achieved. .

Further, a strong retaining strength can be obtained by assembling by manpower without the necessity of an operation tool, so that connection can be simplified and reliability can be improved.

The inner cylinder is provided with a vertically split slit, the outer cylinder has a convex portion on the outer periphery or the inner surface of the tube receiving hole is provided with a slope, or a spiral cam groove is provided in the tube receiving hole. When the cam follower on the outer periphery of the inner cylinder is engaged with the groove, assembly by human power is further simplified.

Further, the projection and the concave portion which are fitted to each other at the mounting point of the stopper on the mating surface of the stopper and the component are provided as follows.
The stopper is prevented from rotating, and the effect of preventing the holder from being naturally decomposed is further enhanced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a holder according to the present invention in a used state.

FIG. 2 is a perspective view of an optical fiber cord as an example of a connection target.

FIG. 3 is a partially broken side view showing a preferred holder embodiment;

FIG. 4 is a partially broken plan view of the holder of FIG. 3;

FIG. 5 is a perspective view of an inner cylinder of the holder of FIG. 3;

FIG. 6 is a sectional view showing a use state of the holder of FIG. 3;

FIG. 7 is a sectional view showing a conventional example of a pipe joint.

[Description of Signs] 1 Inner cylinder 1a Large diameter portion 1b Curved surface 2 Optical connector 3 Tube receiving hole 3a Large diameter portion receiving portion 3b Curved surface 4 Stopper 5 Convex portion 5a Slope 6 Concave portion 7 Convex portion 7a Slope 8 Slit 9 Cam groove 10 Cam follower 11 recess 12 protrusion A optical fiber cord a optical fiber c jacket

Claims (7)

[Claims] 1. A connecting member for a flexible tube having an inner cylinder projecting to the outside, and a stopper having a tube receiving hole, wherein the inner cylinder has a convex portion on the outer periphery at the distal end and a concave portion on an intermediate longitudinal portion. Forming a convex portion which is placed directly above the concave portion in the state where the stopper is mounted on the inner surface of the inner cylinder receiving hole of the stopper, and fitting the connection end side of the flexible tube to the outside of the inner cylinder, Further, a terminal holder for a flexible tube, wherein the stopper is fitted to the outside thereof so that the tube is sandwiched between the inner cylinder and the stopper. 2. The outer diameter of the tube fitting portion of the inner cylinder is equal to or smaller than the inner diameter of the flexible tube, and the inner diameter of the tube receiving hole of the stopper is equal to or smaller than the outer diameter of the tube. 2. The flexible tube end holding device according to claim 1, wherein the radial gap between the protrusion on the outer periphery of the inner cylinder and the protrusion on the inner surface of the inner cylinder receiving hole is smaller than the thickness of the flexible tube. Utensils. 3. The method according to claim 1, wherein the inner cylinder is formed integrally with the mating part, and a protrusion is provided on one of the mutually abutting surfaces of the stopper and the mating part, and the other part is provided with a recess in which the protrusion fits. Item 3. The flexible tube terminal holder according to item 1 or 2. 4. An outer diameter of a base end side of the inner cylinder is made equal to or larger than an outer diameter of a flexible tube, and the inner cylinder is vertically attached to an inner cylinder at a portion in front of the large diameter portion. 4. The terminal holder for a flexible tube according to claim 1, wherein a slit for dividing the flexible tube is provided. 5. A plurality of spiral cam grooves, one end of which is opened at an outlet of the tube receiving hole, are provided in the inner surface of a portion of the tube receiving hole for receiving the large diameter portion of the inner cylinder at a constant pitch in the circumferential direction. A cam follower that is slidably fitted in each cam groove is provided on the outer periphery of the distal end side of the large diameter portion of the cylinder, and further, on the mutual butting surface of the stopper and the mating part,
5. A symmetrically provided two sets of protrusions and recesses which are aligned and fitted to each other at the insertion end point of the inner cylinder with respect to the stopper.
A flexible tube terminal holder according to any one of the preceding claims. 6. The front surface of the inner cylinder outer peripheral convex portion on the tip side of the inner cylinder is a downward slope, and the convex portion of the inner surface of the tube receiving hole is a slope inclined in a direction opposite to the inclined surface. A terminal holder for a flexible tube according to any one of claims 1 to 5. 7. A wire body such as an optical fiber covered and protected by a flexible tube can be drawn into the inside of the connection partner component from the hole of the inner tube by penetrating the hole of the inner cylinder inside the connection partner component. 7. A method according to claim 1, further comprising the step of removing the edge of the hole and increasing the diameter of the hole toward the inlet at the inlet of the hole of the inner cylinder and at the inlet of the tube receiving hole of the stopper. A flexible tube terminal holder according to any one of claims 1 to 3.