JP3380721B2 - Flexible pipe fittings - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible pipe joint for connecting a bellows-shaped flexible pipe. 2. Description of the Related Art Conventionally, as a joint for connecting a flexible pipe (hereinafter sometimes referred to as a flexible pipe) formed in a bellows shape, for example, Japanese Patent Publication No. 3-3837 shown in FIG. Are disclosed. When connecting this joint to the flexible pipe, first insert the cap nut 83 into the flexible pipe 10, open the retainer 80 having an inner surface that engages with the corrugation and provided a slit in the axial direction, open the cut, and open the tip of the flexible pipe. Attach to the part. Then, this is fitted into the large-diameter hole 85 of the joint main body 88, and the female screw 82 of the cap nut and the male screw 84 of the joint main body are screwed into each other, and a few peaks protruding from the end face of the retainer 80 to the end face of the retainer 80. And a gasket 89 to be connected by crimping, that is, crushing, for example, a so-called tightening type. [0003] Another example is disclosed in Japanese Utility Model Laid-Open No. 3-73785. In this joint, as shown in FIG. 5, a joint main body 90 and a tightening member 91 are temporarily assembled in advance, and a retaining ring 93 capable of expanding the diameter is provided.
Is provided between the distal end surface of the tightening member 91 and the packing 92, and the retaining ring 93 is expanded while passing through the flexible pipe.
10 and then push the retaining ring 93 and the packing 92 inward while preventing the expansion of the retaining ring 93 by fully tightening the tightening member 91 to the joint body 90, and the flexible pipe located forward of the retaining ring 93. Are crushed and connected to the inner wall 94 of the joint body, for example, a retightening type. Recently, there has also been proposed a so-called one-touch type joint (for example, Japanese Patent Application Laid-Open No. 5-164280) in which connection can be completed simply by pushing a flexible pipe into a joint body. Since there is no function, the tip of the flexible tube is crushed and complete sealing cannot be performed. In particular, in the case of gas, those with uneasiness in sealing performance are not preferable,
Actually, as in the above two examples, a tightening type or a retightening type in which at least several tips of the flexible tube are crushed has been put to practical use. [0005] Among the above-mentioned conventional flexible pipe joints, the former one has a problem that it takes a lot of time and labor for the connection work because the joint parts are once separated and then assembled. Since this is a tightening work that originally involves friction, it also crushes several tips (2 to 5 peaks) of the flexible pipe, so this tightening work requires considerable force, and the cap nut has to be turned many times. So it takes a long time. [0006] Next, the latter is pre-assembled in a pre-assembled state, and after the flexible tube is pushed in, the connection is completed only by retightening, so that the working time is relatively short. However, since the three peaks of the flexible pipe are crushed against the inner wall in this case, the amount of additional tightening of the fastening member is set to an amount corresponding to a pitch of approximately three peaks of the flexible pipe. The problem here is that there is no guarantee that three ridges will pass through the snap ring when the flexible tube is pushed in, and there is no means for confirming that. That is, even if only one or two peaks are passed through, the same amount of additional tightening is obtained. In such a case, even if the additional tightening is performed, the amount of tightening for two or one mountain is insufficient, and there is a problem that the mountain cannot be completely crushed and leakage occurs from here. [0007] In order to solve this problem, for example, it is conceivable to provide a margin in the retightening amount. However, in this case, since the number of screwing rotations of the fastening member is further increased, there is a problem that a large amount of power and time are required for the connection work as in the previous example. The present invention solves the above problems,
An object of the present invention is to provide a joint for a flexible pipe having a function capable of shortening a tightening force and a time in a connection work, and having a function of easily confirming that a flexible pipe has been normally pushed. SUMMARY OF THE INVENTION The present invention has an inner surface engaged with an outer surface of a bellows-shaped flexible tube and a plurality of cuts in an axial direction, and is capable of expanding and contracting to reduce the diameter. A retainer for engaging the outer surface of the flexible tube, a wall abutting on the rear end of the retainer, an inner diameter capable of inserting the flexible tube, and a nut having a female thread formed on a front portion; and a retainer interposed between the retainers. Has a locking member placed so as to cancel the diameter expansion by moving the flexible tube to the back side and a male screw screwed into the female screw of the nut at the front, and a rear portion at the rear. The joint body and the nut are formed via a retainer, and the distal end of the flexible tube is brought into contact with the back wall via the locking member. When the retainer comes into contact, the retainer shrinks in diameter, A flexible pipe joint which is screwed in advance with an additional tightening amount leaving one mountain at the end to be engaged with the outer surface thereof, and which, when tightened, presses one mountain of the end of the flexible pipe to the inner wall. It is. According to the joint for a flexible pipe described above, the joint body and the nut are preliminarily tightened so that the distance between the front end of the retainer and the back wall allows only one tip of the flexible pipe to pass therethrough. Leave it together. At the same time, the tip of the flexible tube 1
Since the expanded state of the retainer is released when the mountain is inserted, when the flexible tube is inserted through the retainer, the distal end collides with the back wall and cannot be further advanced. At the same time, the entire retainer is reduced in diameter and engages with the first valley and thereafter. In this state, once the flexible pipe is to be pulled out, the flexible pipe cannot be pulled out because the retainer is locked in the valley next to the tip of the tip. This makes it possible to confirm that the flexible tube has been inserted normally. Conversely,
If the flexible tube is actually pulled out while trying to be pulled out, it means that the insertion of the flexible tube has been prevented or the retainer is not in a reduced diameter state, and it is possible to know here that it is necessary to push the flexible tube further. It has such a tube insertion confirmation function. In addition, crimp one tip of the flexible pipe,
In other words, only crushing is required, so that the force required for tightening and the time required for connection are reduced. Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are sectional views of a joint for a flexible pipe showing one embodiment of the present invention. FIG. 1 is a cross-sectional view showing a state before the flexible pipe is inserted, FIG. 2 is a cross-sectional view showing a state where the flexible pipe is inserted, and FIG. 3 is a cross-sectional view showing a state after the retightening is completed. The joint for a flexible pipe has a joint body 51.
, A nut 52, a retainer 53, a locking member 54,
Reduced diameter ring 55, O-ring 56, watertight packing 46
Consists of In this embodiment, the locking member 54 also functions as a gasket. On the other hand, the flexible pipe 7 to be connected has a cut portion 7a, a crushed first peak 7b, a first valley 7c, a second valley 7d, a second valley 7e,. The outer surface is covered with a protective layer 8 made of synthetic resin. The joint body 51 includes a male screw 41 screwed to the nut from the inlet side (left side in the drawing) and a through hole 5.
9, a back wall 57 is formed as a step surface.
The nut 52 has a joint body 51 from its front (right side in the drawing).
A female screw 42 to be screwed with the male screw 41, a rear wall 43 for holding a retainer 53, which will be described later, between the front end surface 44 of the joint body, and an inner diameter through which the flexible pipe can be inserted are provided on the inner surface of the rear end. Is formed. The retainer 53 is a stopper for the flexible pipe, and is capable of being expanded and contracted so as to engage with the first and second valleys of the flexible pipe when the diameter thereof is reduced. This has a shape having a corrugated inner surface to be locked to the outer surface of the flexible pipe and four split grooves in the circumferential direction, and a projection 45 of the locking member 54 intervening between each split groove. A diameter-reduced ring 55 having a contraction force in the inner diameter direction is fitted on the outer periphery of the retainer so that the diameter can be reduced and the diameter can be reduced. The locking member 54 includes a projection 45 and a gasket, and the projection is interposed in advance between the retainers as described above. When the flexible tube is inserted, the cutting portion 7a pushes the gasket portion to the rear side, and when the first mountain portion 7b passes through the retainer 53, the engagement of the projection portion 45 with the retainer is released. The diameter of the flexible pipe is reduced by the force of the diameter ring 55 and the flexible pipe is engaged from the first valley to the second valley. Next, the procedure for connecting the joint for a flexible pipe of this embodiment will be briefly described. FIG. 1 shows a state before the flexible tube 7 is inserted. As described above, when the diameter of the retainer 53 is reduced, the retainer 53 is locked from the first valley portion to the second valley portion excluding one tip of the flexible tube. It is screwed in advance so as to be sandwiched between the joint body 51 and the nut 52 while leaving the amount of tightening. The collar 58 is mounted to maintain this screwed state. Next, when the flexible pipe 7 to be connected is inserted from the rear end of the nut 52, the cut end 7a of the flexible pipe 7 pushes the locking member 54 inward as shown in FIG.
At the same time, the engagement of the projecting portion 45 is released, and the retainer 53 is reduced in diameter and engaged except for one peak at the tip of the flexible tube. Therefore, even if the flexible tube 7 is pulled out here, it does not come out of the joint body. Conversely, when the flexible tube comes off, it means that the flexible tube has not passed through the retainer portion, and it can be confirmed that further pushing is necessary. Next, when the collar 58 is removed and the nut 52 is rotated to retighten the joint body 51, the retainer 53 advances to the rear side as shown in FIG. The flexible pipe and the joint body are completely sealed by the gasket portion. The connection of the flexible tube 7 is completed as described above. The above embodiment is an embodiment in which a retainer whose diameter can be freely increased is used. However, the present invention is not limited to this embodiment.
When the joint body and nut are tightened, the end of the flexible pipe 1
What is necessary is just what was comprised so that mountain parts might be crimped. As described above, in the joint for a flexible pipe according to the present invention, since only one tip of the flexible pipe is crushed, the tightening force and time in the connection work can be reduced. Furthermore, even if the connection can be made simply by pushing in the flexible tube and tightening the nut, there is a function to easily check whether the flexible tube is properly pushed in when pushed in. Can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view showing a temporarily assembled state of a flexible pipe joint according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing a state in which a flexible pipe is inserted in the flexible pipe joint according to the embodiment of the present invention. FIG. 3 is a longitudinal sectional view showing a state after a flexible pipe is connected in the flexible pipe joint according to the embodiment of the present invention. FIG. 4 is a longitudinal sectional view showing an example of a conventional flexible pipe joint. FIG. 5 is a longitudinal sectional view showing another example of a conventional flexible pipe joint. [Description of Symbols] 51 ... joint body 52 ... nut 53 ... retainer 54 ... gasket (locking member) 55 ... reduced-diameter ring 56 ... O-ring 58 ... collar 59 ... through-hole 41 ... male screw 42 ... female screw 43 ... rear Wall 7: Flexible tube 8: Resin coating layer

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiyuki Ueno 71-4 Yukojihama, Joetsu-shi, Niigata (72) Inventor Shinichi Kamata 3-1-21-108, Kamiigusa, Suginami-ku, Tokyo (72) Inventor Takashi Anamizu 404, Itogaya Natocho, Nidocho, Shinjuku-ku, Tokyo 404 (72) Inventor Yuzuo Saito 1-1-11-11 Unoki, Ota-ku, Tokyo (72) Inventor Fumitaka Sato 3-27- Nishi Ichinoe, Edogawa-ku, Tokyo 15 (56) References JP-A-4-58697 (JP, U) JP-A-3-100688 (JP, U) (58) Fields studied (Int. Cl. ⁷ , DB name) F16L 33/00 F16L 9 / 06 F16L 19/02 F16L 33/28 F16L 57/00

Claims (1)

(57) [Claims 1] An inner surface engaging with the outer surface of a bellows-shaped flexible tube and a plurality of cuts in an axial direction, and are capable of expanding and contracting, and have an outer surface of the flexible tube when the diameter is reduced. A retainer to be engaged, a nut having a female thread formed at the front and an inner diameter through which a flexible tube can be inserted into a wall abutting the rear end of the retainer; and A locking member placed to release the diameter expansion by moving the flexible tube to the back side, and a male screw screwed into the female screw of the nut at the front, and a rear portion of the locking member at the rear. The joint body and the nut are formed via a retainer, and the retainer is reduced in diameter when the distal end of the flexible tube comes into contact with the back wall via the locking member. Engage with the outer surface except one tip So that smoothing is previously screwed to leave tightening amount, increasingly flexible pipe joint characterized by crimping one peak fraction tip of the flexible tube inner wall when clamped.