JPS6318069B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an airtight joint device that connects a covered flexible tube and a joint body by tightening them with a lock nut, in which the connection work can be easily performed with low tightening torque. The present invention relates to an airtight flexible pipe joint device that can maintain airtightness against gas, liquid, oil, etc. over a long period of time, and strengthens the tensile strength between the flexible pipe and the joint device.

Conventionally, in this type of joint device, a coated flexible tube 2' as shown in FIG. 5A is often used. A large amount of PVC material was used until the surface was coated with PVC material and made uniformly smooth, but in line with the era of energy saving and material saving, electrical piping work that does not require thick coated flexible pipes. etc.,
A relatively thin PVC-coated flexible tube 2 with a predetermined thickness, as shown in FIG. 5B, has come into use. Since the PVC material is thinly coated 2b, the outer surface also has an uneven surface, and conventional coupling devices do not adhere tightly, resulting in problems such as not being able to maintain airtightness against gas leaks, oil leaks, etc. In addition, since the conventional product has a terminal cap 6 mounted on the end of the coated flexible tube, the end portion 6c may be plastically deformed as shown in FIG. 6A, or the terminal cap 6 may be deformed as shown in FIG. 6B. Since the end portion 6c is flared and the wedge-shaped sleeve 6d made of nylon or the like is press-fitted, there is a problem in that the flexible tube 2' and other parts cannot be reused. In addition, the work of assembling the parts in the state shown in Fig. 6A and B is difficult due to the large screw-in torque of the tightening nuts, is time consuming, is costly, and requires skill in construction. points are listed.

In view of such conventional defects, the present invention forms the end portion 6c of the terminal cap 6 in a mountain shape, and newly adds the gland packing 5 and the taper sleeve 4.
By intervening and tightening the tightening nut 3, airtightness can be maintained for both conventional and uneven covered flexible tubes 2', 2, and airtightness can be maintained easily with low tightening torque. The present invention aims to provide a flexible pipe joint device.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings of embodiments. As shown in FIG. 1, this coupling device 1 has a lock nut 3 inserted through a flexible tube 2 having an outer sheath made of soft synthetic resin, etc., and further has a V-shaped cross section on the side in contact with the gland packing. An annular taper sleeve 4 with a concave L shape and an annular gland packing 5 made of an elastic material with a cross section protruding in a chevron shape on both sides, a groove on the outer periphery, and a flat concave inner periphery.
is inserted through the flexible tube 2, and a terminal cap 6, in which an inner tube and an outer tube are integrally molded so as to match the cut of the tube, is mounted on the end of the flexible tube 2. 2 is inserted and fitted into the inner cavity of the joint body 7, and the lock nut 3 is screwed into the connecting thread of the large diameter portion of the joint body 7 and fastened.

Next, the terminal cap 6 will be explained according to FIG. The terminal cap 6 is a coated flexible tube 2
The inner cylinder part and the outer cylinder part are integrally molded so as to sandwich the end tube body from the inside and the outside. A thread-like raised protrusion 6a is provided around the inner cylinder part so as to be screwed into the spiral groove of the inner pipe part of the flexible tube 2, that is, the metal conduit 2a, and the end 6b of the protrusion 6a is provided with a PVC electric wire or the like. It is bent so as not to damage the covering of electric wires, etc. when passing through. Further, the outer cylinder part is formed into a mountain shape so that the end part 6c is in contact with the inclined surface of the inner cavity of the joint body 7 and the side surface 5b of the gland packing 5.

Next, the gland packing 5 will be explained according to FIG. 4A. This annular gland packing 5 has a groove 5a on the outer periphery of the middle part in the width direction, and both ends in the outer diameter width direction are formed with chevron-shaped protrusions 5b, one of which is a V-shaped concave surface of the tapered sleeve 4. The other side is in contact with a V-shaped recess formed by the inclined surface of the inner cavity of the joint body 7 and the end 6c of the terminal cap 6, and the inner peripheral surface is simply cylindrical.

In addition, as another example of the gland packing 5, as shown in FIGS. 4B, C, and D, a plurality of grooves may be provided, or the groove attachment position may be provided on the inner or outer periphery. Further, the shape of the groove may be formed as shown in FIG. 4E depending on its use, and may be provided on the outer or inner circumference. Since both bulge mainly in the inner diameter direction, the effect of ensuring airtightness is the same as that of this embodiment.

Since this invention relates to the above-mentioned configuration, as shown in FIG. 2, when the mounting screw part 7a of the coupling device 1 is inserted into the through-hole part of the control panel etc. 8 and tightened with the tightening nut 7d, the packing 7b spreads to the full extent of the spare space of the seal seat 7c so as to effectively utilize its elastic limit to ensure airtightness. Further, when the lock nut 3 is screwed forward, the fitted taper sleeve 4 and gland packing 5 are propelled, and the gland packing 5 eventually connects to the inclined surface of the inner cavity of the joint body 7, the end 6c of the terminal cap 6, and the taper sleeve 4. The groove 5a is closed by being squeezed, and if the left and right inner walls of the groove 5a are further squeezed to the point where they come into contact with each other, the widthwise central part of the inner circumferential surface will bulge hard toward the center, and this bulge will be removed. The flexible tube 2 is tightly attached to the covering portion 2b of the flexible tube 2 through which the portion is inserted. At the same time, the protrusion 5b of the gland packing 5 connects to the end 6c of the terminal cap 6.
Press the inclined surface of the inner cavity of the joint body 7 to make a tight contact and ensure airtightness. As described above, the coated flexible tube 2 is tightly fitted with the terminal cap 6.
Due to the expansion of the packing 5, the convex and concave surface of the outer cover is completely in close contact with the joint body 7, preventing gases, liquids, etc. from entering from the outside.
It will be completely airtight against oil, etc.

As described above, the coupling device 1 according to the present invention can be used for flexible tubes with any surface shape, whereas conventional products are limited to flexible tubes 2 with almost smooth surfaces. Conventionally, when capping a flexible pipe with cap 6, it was necessary to tighten it using a special tool, but the advantage is that it can be completely capped by simply screwing it into the spiral groove, and has a high airtightness. Furthermore, when attaching the flexible pipe to the fitting body, conventional products require a large amount of tightening torque, requiring great effort and skill, but thanks to the action of the gland packing and tapered sleeve, it can be fastened with a low tightening torque. This has made work much easier and more reliable. Furthermore, regarding electrical grounding, conventional products have a metal touch system, so if the tightening becomes loose, the grounding performance deteriorates and the electrical resistance value increases.However, sufficient grounding is maintained due to the pressing action of the elastic material. It became possible to do what I could. In addition, the tensile strength between the flexible tube and the joint body has increased due to the bulging action of the elastic material, which increases the gripping force (clamping force) caused by pressing and tightening, making it sufficiently resistant to considerable external forces.

In the present invention, as described above, the gland packing is inserted into the V-shaped recess of the joint body and the tapered sleeve by fitting both sides of the gland into the V-shaped recess, so that the two do not shift or come off, and the lock nut is secured. When tightened, the flexible tube and the joint body are firmly fixed together by the strong adhesion force due to the swelling action of the gland packing, and can sufficiently withstand large tensile forces.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a main part of a coupling device according to an embodiment of the present invention in cross section, FIG. 2 is a plan view when the above connection is completed, and FIG. 3 is a partially cross-sectional plan view of a terminal cap. FIGS. 4A, B, C, and D are cross-sectional views of another example of the gland packing, E is an explanatory view of an example of the groove, and FIGS. 5A and B are plan views of a part of the covered flexible tube in cross section.
FIGS. 6A and 6B are cross-sectional plan views of the main parts of the conventional example. Description of symbols, 1...Joint device, 2...Coated flexible tube, 2a...Metal conduit, 2b...Coated part, 3...
Lock nut, 4...Taper sleeve, 5...Gland packing, 5a...Groove, 5b...Protrusion, 6
...Terminal cap, 6a...Protrusion, 6c
... end, 6d ... sleeve, 7 ... joint body,
7a...Mounting spiral tube part, 7b...Packkin, 7c...
...Patsukin seat, 7d...Natsuto, 8...control panel, etc.

Claims (1)

[Claims] 1 In a flexible pipe joint, terminal cap 6
The end 6c of the outer cylinder part is bent into a mountain shape and fitted into the joint main body 7, and a V-shaped recess is formed with the inner inclined surface of the joint main body 7, and the tapered sleeve 4 faces the V-shaped recess. A V-shaped recess is provided in the end face of the space, and a gland packing 5 is interposed in both spaces, and both sides of the cross section of the gland packing 5 are provided with chevrons that fit into the V-shaped recesses of both the spaces. , and one or more grooves 5a are provided on the outer periphery of the middle part in the width direction, and this gland packing 5 is inserted into the space and tightened with a lock nut 3. An airtight flexible pipe characterized in that the left and right inner walls of the groove 5a of the groove 5a are pressed together so that they are in contact with each other, and the inner circumferential surface of the groove 5a is largely bulged toward the center so that the flexible tube is airtightly fixed to the joint body. Pipe fitting device.