JP3705506B2 - Corrugate pipe fitting sleeve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sleeve suitable for a pipe joint for connecting a metal corrugate pipe (hereinafter simply referred to as a pipe) having a corrugated outer peripheral surface.
[0002]
[Prior art]
Conventionally, for example, Japanese Patent Publication No. 3-3837 (USP 4,630,850) has been proposed and used as a joint for connecting a corgate pipe.
This joint is composed of a joint body having a screw on the outer periphery of one end, a cap nut screwed into the male thread of the joint body, and a sleeve having a waveform on the inner peripheral surface that engages with the corrugation of the corgate pipe. Yes.
Of these, the joint body has a tapered hole portion that is uniformly reduced in diameter toward the back at the inner periphery on the male screw side, and a smaller diameter passage than the tapered hole portion on the inner periphery of the other end portion. There is a hole, and a pipe receiving wall portion is provided at the boundary between the through hole and the tapered hole portion.
The sleeve has slits in the axial direction and has a plurality of segments. After attaching this sleeve to the outer periphery leaving several peaks from the end of the corrugate tube, insert this sleeve into the tapered hole of the joint body, and screw the cap nut into the male thread of the joint body from the outside of the sleeve. Tighten the nut.
Thus, several crests of the corrugate tube protruding from the end portion of the sleeve are crushed between the front end portion of the sleeve and the tube receiving wall portion of the joint main body to be connected and sealed.
[0003]
[Problems to be solved by the invention]
As described above, the sleeve used for this joint is a plurality of divided segments having a waveform that engages with the corrugation of the corrugate pipe on the inner peripheral surface. There is an annoyance that it is necessary to disassemble the joint and to fit the sleeve around the outer periphery of the corgate pipe. Furthermore, there is a problem that labor and force are applied, such as inserting the sleeve-equipped corrugate pipe into the joint body, screwing the cap nut, and crushing several peaks at the end of the pipe. Furthermore, there was a problem that the parts of the joints that were disassembled were dropped from the hand during the piping work and the parts were lost.
[0004]
Therefore, the present invention is a sleeve suitable for use in a joint that has been preliminarily assembled, and the pipe and the sleeve can be easily engaged by inserting the corgate pipe without disassembling the joint when connecting the joint and the corgate pipe. It provides a sleeve that is compatible and cannot be easily removed.
[0005]
[Means for Solving the Problems]
The present invention includes a plurality of metal segments having a protruding portion protruding toward the radially inner diameter side at one end and a contact surface at the other end contacting the pressing surface formed on the nut, and the metal segments A sleeve made of a composite member with a ring-shaped synthetic resin substrate formed integrally,
Each of the metal segments forms a plurality of slits extending in the axial direction between the metal segments, and a substantially circular hole inner diameter formed by the tip of the projection is a peak of a corrugate tube to which the metal segment is connected. Is arranged at the front of the sleeve so that it is smaller than the diameter of and slightly larger than the diameter of the valley,
The ring-shaped synthetic resin base has a ring-shaped synthetic resin ring body formed at the rear portion of the sleeve, and is molded so as to be integrated with each metal segment via the ring body,
When the corrugate pipe is pushed in from the rear part of the sleeve, the projection on the front part expands and climbs over the ridge of the corgate pipe, and then shrinks to enter the valley. It is a sleeve.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The sleeve of the present invention is formed by integrally molding the metal segment with a synthetic resin member. At this time, the front part of the sleeve receives the pressing force of the nut, and it is locked to the valley of the corrugate tube, and it is necessary to crush the crest portion of the tip against the back wall of the joint. Since it is necessary to form a metal piece segment with high rigidity and to expand (expand outward) on the other hand, a plurality of slits are provided in the axial direction and the resin portions are connected. Therefore, when the corrugate tube is pushed in, the protruding portion of the sleeve expands by using the elastic force of the slit and the resin portion with the rear portion as a fulcrum, gets over the mountain of the tube, and shrinks when it reaches the next valley ( (Returns to the original state) enters the valley and locks. (A movement in which the protruding portion of the front portion elastically expands and climbs over the crest of the tube with the rear portion of the sleeve as a fulcrum is referred to as an elastic pivot motion in the present invention.)
On the other hand, since it is necessary to adjust the position of the projection of the sleeve to the position of the recess of the joint body so that the projection can be expanded, an engagement portion with a nut is provided at the rear, and the above-mentioned projection is expanded and contracted. The whole was made into a ring-shaped synthetic resin base so as to facilitate the pivot movement. Therefore, the engaging portion of the nut and the sleeve functions as a fulcrum for the elastic pivot motion, and at this time, the protrusion of the front portion of the sleeve is more easily expanded due to the elasticity of the synthetic resin base.
[0007]
【Example】
FIG. 1 is a partial cross-sectional front view showing an embodiment in which a sleeve of the present invention is used for a joint, where a nut and a joint body are temporarily assembled and a corrugate pipe is inserted. FIG. 2 is a front view showing a partial cross-section in a state where the nut of the joint of FIG. 1 is tightened. FIG. 3 is a perspective view of the sleeve of the present invention.
[0008]
Hereinafter, embodiments will be described with reference to the drawings. First, as for the joint, reference numeral 1 denotes a joint body, and a through hole 11 is opened in the axial direction, and a shoulder 14 having an airtight surface facing one side (left in the drawing) is formed in the through hole 11. are doing. In this example, a heat-resistant gasket 12 is attached, and a rubber packing 13 containing expanded graphite is provided almost in contact therewith. A tapered inner peripheral surface 15 that is reduced in diameter toward the shoulder portion 14 is provided next to it (the taper may be provided on a part of the inner surface), and an annular concave groove 16 and the concave portion are adjacent thereto. A female screw 17 having a diameter smaller than that of the groove is provided side by side, and a notch 18 for accommodating the O-ring 36 is provided at an end thereof. On the other side (right side) of the joint main body, a male screw 19 for attaching the joint main body to other pipes or instruments is provided.
[0009]
The nut 3 is provided with a male screw 31 to be screwed into the female screw 17 of the joint body 1 on the outer periphery of one end portion, and a concave groove serving as an engaging portion is cut out at an inner end portion of the male screw 31. A protrusion 32 is provided. On the other hand, the tip of the nut 3 is a pressing surface 33 that presses against the contact surface 24 of the sleeve. Further, an E-shaped packing 37 is attached to the opposing portion of the nut 3 and the resin cover 41 of the corrugate tube, thereby preventing moisture from entering the joint.
[0010]
Now, the sleeve 2 that holds the free end of the corrugate tube 4 is positioned in the through hole 11 of the joint body 1 in a state in which the sleeve 2 is attached to the nut in advance. As shown in FIG. 3, the sleeve 2 has a ring 21 made of a synthetic resin at the rear, and the front is divided into segments 22 by a plurality of slits (here, five) extending in the axial direction. At the tip of each segment, that is, the portion facing the shoulder portion 14 in the through hole 11 of the joint body, there is a projection 23 protruding toward the inside in the radial direction. The circle formed by the tip of the projection 23 is smaller than the diameter of the peak of the corrugated tube to be inserted and slightly larger than the diameter of the valley.
[0011]
The sleeve 2 is a composite member in which a ring-shaped synthetic resin base and a metal segment are integrally formed. That is, most of the segment 22 including the protrusion 23 and the contact surface 24 is a metal segment made of a brass plate, and the ring body 21 itself and the inner peripheral portion of the segment 22 (portion indicated by 27 in FIG. 1) and FIG. It consists of a ring-shaped synthetic resin base | substrate over the outer peripheral part shown by 22. These metal segments 26 are integrally formed through slits. Therefore, by providing the slit and connecting with the resin body, the protrusion 23 portion can be easily expanded and contracted elastically with the portion of the ring body 21 as a fulcrum. Further, the projection 23 having high rigidity can crush the peak portion of the tip of the corrugate tube, and the contact surface 24 can receive a strong force from the nut 3. The contact surface 24 has a portion covered with resin as shown in the figure, and the entire surface does not necessarily have to be a metal portion. Further, a plurality of claws 25 serving as engaging portions with the nut are provided on the outer periphery of the rear end portion of the ring body 21 at the rear portion of the sleeve, and the claws are elastically fitted into the groove portion on the nut 3 side and are rotatably attached. The sleeve 2 is allowed to move axially relative to the nut 3 and is prevented from moving away.
[0012]
Next, a procedure for connecting a corrugate tube will be described. First, a spacer ring or the like is attached, leaving a tightening amount of about one mountain of the corrugate pipe to be connected to the nut 3 and the joint body 1, and a joint assembled in a temporarily tightened state is prepared. (This joint is assembled at the factory in advance.)
The resin cover of a length of 4 to 5 is removed from the end of the corrugate tube 4 and inserted into the joint from the opening of the nut 3 (from the left side of the drawing). Then, the tip of the corrugate tube 4 or the crest 42 of the tip pushes the projection 23 of the sleeve 2 to the back, so that the corgate tube and the sleeve together advance to the back until the catch of the sleeve claw 25 and the nut projection 32 is allowed. . When the innermost position is reached, the outer peripheral portion of the projection 23 at the tip of the sleeve is located at the annular groove 16 of the joint body. When the tube is further pushed in, the front portion of the sleeve is cracked by the slit and the resin body has elasticity, so that the protrusion 23 is elastically expanded with the rear ring portion 21 as a fulcrum along the mountain of the corrugate tube. Then, the projection 23 opens and climbs over the peak 42 at the tip of the corrugate tube, and then the projection 23 enters and locks into the first valley 43 while being reduced. Here, since the distance from the protrusion 23 at the tip of the sleeve to the shoulder inside the main body (in this example, the fireproof gasket 12) is a length corresponding to about one mountain of the corrugate tube, the protrusion 23 of the sleeve is one of the corrugate tubes. The tip of the corrugate tube hits the refractory gasket 12 in the state where it enters the second valley 43 so that it cannot be inserted any further.
[0013]
Here, a structure in which only one mountain can be inserted is more preferable than a structure in which several tubes can be inserted because it can be determined whether the tube has been normally inserted deeply or not. Because, as described above, the sleeve projection 23 enters the first valley 43 of the corrugate tube and cannot be inserted any more. Therefore, once the corrugate tube is pulled out in this state, the sleeve is retracted together with the tube. The protrusion 23 deviates from the position of the groove 16. Moreover, since the outer peripheral surface of the segment 22 fits into the female thread 17 portion of the joint body, the projection 23 cannot be opened, and the tube cannot be blocked and pulled out. As described above, since the tube does not come off, it can be confirmed that the corrugate tube has been normally inserted, and the crushing allowance of the tube is also normal, so that it can be reliably sealed. On the other hand, when the corrugate tube is pulled out, it means that the projection 23 has not climbed over the peak 42 at the tip of the corrugate tube, and it can be seen that it is not properly connected. At this time, if the structure can be inserted in two or three peaks, even if only one peak is inserted, there is a disadvantage that the tube will not come out but there is no allowance for crushing the tube. There is a problem that cannot be done. Although the present invention is not limited to one mountain, the above-mentioned one mountain means that it may be in the range of 0.5 mountain to 1.5 mountain.
[0014]
Thereafter, when the male screw 31 of the nut is tightened along the female screw 17 of the main body, the sleeve 2 rotates with respect to the rotation of the nut 3 after the pressing surface 33 of the nut hits the contact surface 24 of the sleeve. Since the tube is flexible, the sleeve 2 is pushed toward the back of the through hole 11 of the main body as the nut 3 is tightened without twisting the tube. There is a taper inner peripheral surface 15 at the back of the through hole 11 of the main body, and the inner diameter of the taper inner peripheral surface 15 becomes smaller as it goes deeper. I will do it. Therefore, the protrusion 23 at the end of the sleeve is tightened in the radial direction while keeping the first trough 43 of the corrugate tube 4, and the peak 42 at the end is crushed to the fireproof gasket 12 of the shoulder 14 to obtain complete airtightness. Connecting.
[0015]
In order to determine the position of the nut 3 and the joint body 1 when assembled in the above-described temporarily tightened state, a spacer ring 5 is inserted between the nut end face and the body end face, and the nut 3 is fastened to the joint body 1 in advance. It is desirable that the size of the spacer ring 5 is a length obtained by adding a distance between the protruding portion of the sleeve and the shoulder gasket surface of the main body and a crushing margin, and is set on the basis of the length of about one mountain of the corgate tube. . The spacer ring 5 is made of an elastic plastic or the like, and has a substantially C-shape with a notch in the axial direction at a part of the circumference. In this way, in a state where the nut is weakly tightened to the main body, the spacer ring 5 is sandwiched between the nut and the end surface of the main body so that the position of the nut can be obtained. However, when the nut is strongly tightened, the spacer ring 5 is broken at the notch and is detached from between the end surface of the nut and the main body and attached to the outer periphery of the main body. In addition, after inserting the corrugate tube, the spacer ring 5 between the nut and the end face of the main body can be removed by hand.
[0016]
【The invention's effect】
The sleeve of the joint for connecting a corrugate pipe of the present invention can be easily locked to the valley of the corrugate pipe by inserting the corgate pipe into the joint body without disassembling the joint body such as the joint main body and the nut, and thereafter It is hard to come out and always make a correct connection. In addition, the metal part segmented by the slit is connected to the front part of the sleeve with a synthetic resin, and at the same time, the rear part is a composite member integrally molded with a synthetic resin body. Can be reliably crushed and sealed, and the protrusion of the retainer is easily expanded and contracted by a slit and an elastic synthetic resin body. Therefore, connection work can be performed smoothly, simply and reliably.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view showing an embodiment of a joint using a sleeve of the present invention, showing a state where a corrugate pipe is inserted after provisional assembly.
FIG. 2 is a partial cross-sectional view showing a state in which a nut is tightened.
FIG. 3 is a perspective view of a sleeve of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Joint body 2 Sleeve 3 Nut 4 Colgate pipe 5 Spacer ring 11 Through-hole 12 Heat-resistant gasket 13 Rubber packing 14 with expanded graphite Shoulder part 15 Tapered inner peripheral surface 16 Annular groove 17 Female thread 18 Notch 19 Male thread 21 Ring Body 22 Segment 23 Protrusion of sleeve 2 24 Contact surface 25 Claw 26 Brass plate (metal segment)
27 resin 31 external thread 32 nut 3 of the protrusion 33 pushing surface 36 O-ring 37 E-shaped packing 41 resin cover Korugeito tube 4 42 Korugeito tube tip of the mountain 43 Korugeito tube The first valley

Claims (1)

A plurality of metal segments having a protruding portion protruding toward the radially inner diameter side at one end and an abutting surface at the other end abutting against a pressing surface formed on the nut, and these metal segments are integrally formed A sleeve composed of a composite member with a ring-shaped synthetic resin substrate,
Each of the metal segments forms a plurality of slits extending in the axial direction between the metal segments, and a substantially circular hole inner diameter formed by the tip of the projection is a peak of a corrugate tube to which the metal segment is connected. Is arranged at the front of the sleeve so that it is smaller than the diameter of and slightly larger than the diameter of the valley,
The ring-shaped synthetic resin base has a ring-shaped synthetic resin ring body formed at the rear portion of the sleeve, and is molded so as to be integrated with each metal segment via the ring body,
When the corrugate pipe is pushed in from the rear part of the sleeve, the projection on the front part expands and climbs over the ridge of the corgate pipe, and then shrinks to enter the valley. sleeve.

Images