JP3030497B2 - Pipe connection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe connecting device, and more particularly, to a pipe inserted into a hole of a main body, a contractible member on an outer peripheral side thereof is compressed in an axial direction to come into contact with the pipe in a retaining state. The present invention relates to a pipe connection device.

[0002]

2. Description of the Related Art FIG. 8 is an explanatory view of a conventional pipe connection device. The conventional pipe connection device shown in FIG.
(P), a tubular main body (9a) into which the pipe (P) is inserted,
A large-diameter hole (91) formed in a predetermined range from one end of the main body (9a) in an inner peripheral hole of the main body (9a);
A ring member (9c) having a V-shaped cross section which is disposed at the inner end of the pipe (P) on the outer peripheral side and is convex on the inner peripheral side, and the large-diameter hole (9)
1) Screwed into the main body (9a) in the inserted state with respect to (1) and the pipe (P)
And a screw cylinder (9b) into which the screw is inserted.

[0003] In this device, when a screw cylinder (9b) is tightened in a state where a pipe (P) is inserted into a main body (9a), a ring member is formed.
(9c) is pressed by the screw cylinder (9b) and compressed in the axial direction. At this time, since the ring member (9c) is formed in a V-shaped cross section that is convex on the inner peripheral side, the inner peripheral portion of the ring member (9c) is displaced inward by the compression, Is displaced. During this displacement process, the inner periphery of the ring member (9c)
(P) comes into contact with the retaining state, and the degree of the contact increases as the displacement progresses.

[0004] When the outer peripheral ends of the pair of tapered portions constituting the ring member (9c) come into contact with each other by tightening the screw cylinder (9b), the displacement, that is, the displacement of the ring member (9c). Compression ends. In this state, the inner peripheral portion of the ring member (9c) bites into the pipe (P), and the pipe (P) is fixed to the main body (9a). In this case, the constituent wall of the pipe (P) is plastically deformed to protrude toward the inner circumference due to the bite of the inner circumference into the pipe (P).

In this apparatus, a pipe (P) is attached to a main body (9a).
Since the pipe (P) is fixed to the main body (9a) simply by tightening the screw cylinder (9b) in a state where the is inserted, the operation for fixing is easy. However, in this case, the pipe (P)
When the tube (P) is inserted into the main body (9a), the tip of the tube (P) does not hit anything, so that the position of the tube (P) cannot be determined at the time of the insertion. After the inner peripheral portion of the ring member (9c) comes into contact with the pipe (P) in a retaining state, the pipe (P) moves inward with the displacement of the inner peripheral portion of the ring member (9c). Side, the insertion depth (A) from the large-diameter hole (91) increases, so even when the screw cylinder (9b) is tightened, the position of the pipe (P) greatly changes inward. I do.
Therefore, it is difficult to position the pipe (P) with respect to the main body (9a).

[0006]

FIG. 9 is an explanatory view of another pipe connection device. On the other hand, as shown in FIG.
The pipe (P) is located on the inner side of the large diameter hole (91) in the inner peripheral hole of (a).
It is conceivable to provide an annular stepped portion (92) with which the tip of the abutment contacts. In this case, the pipe (P) inserted into the main body (9a) is positioned with respect to the main body (9a) by the contact.
Also, when the screw cylinder (9b) is tightened,
(P) does not move and is positioned as described above.

However, when the screw cylinder (9b) is tightened,
Since the tip of (P) is in contact with the annular step (92), the inner periphery of the ring member (9c) and the pipe (P) in the tightening process.
As the degree of contact with the pipe increases, the pipe (P)
The drag acting on the surface increases. This allows the screw cylinder (9
The torque required for tightening in b) increases. In particular, in the final stage of the tightening, the torque becomes extremely large.

It is an object of the present invention to provide a pipe connecting apparatus which improves the positioning performance of an inserted pipe and reduces the force required for fixing the pipe.

[0009]

Means for solving the problem of the invention according to the first aspect of the present invention are as follows: a pipe to be connected, a main body having a hole into which the pipe is inserted, and a tip of the inserted pipe. Blocking means for preventing the insertion of a predetermined amount or more by abutting against the pipe; a compressible member arranged on the outer peripheral side of the inserted pipe in the hole and compressed by a force applied in an axial direction; A movement preventing means for preventing the inward movement of the shrinkable member, and a pressing member attached to the main body so as to be able to press the shrinkable member from the outside, the shrinkable member includes: The tube-side end is displaced inward while being displaced inward by compression by the pressing of the pressing member, and comes into contact with the tube in a retaining state, and the blocking means is provided on the peripheral wall of the hole. A tapered step formed and progressively decreasing in diameter inwardly; A ring body interposed between the stepped portion and the ring body, the ring body has a diameter when the inward acting force generated in the pipe in the retaining state becomes a predetermined value or more. The blockage is reduced and moved inward of the step to release the blockage. "

In this structure, when the tube is inserted into the hole of the main body, the distal end surface of the tube comes into contact with the ring as the blocking means, and the ring comes into contact with the step. Touch These abutments prevent the tube from being inserted beyond a predetermined amount. In this state, when the compressible member is pressed in the axial direction by the pressing of the pressing member, the tube-side end of the compressible member is displaced inward while being displaced inwardly with respect to the tube. Touch the retaining state. When in contact, the tube produces an inwardly acting force. When the acting force becomes equal to or more than the predetermined value due to the continuation of the compression, the ring body is reduced in diameter and moves to the inside of the stepped portion. It is released.

[0011]

[0012]

According to the second aspect of the present invention, the ring body may include a notch formed in a part of the circumferential direction in the axial direction. Further, the one having no notch may be used. According to the third aspect of the present invention, "the pipe to be connected, the main body having the hole into which the pipe is inserted, and the tip of the inserted pipe are prevented from being inserted beyond a predetermined amount. Blocking means, a compressible member arranged on the outer peripheral side of the inserted tube in the hole and compressed by an axially applied force, and preventing the compressible member from moving inward. A movement preventing unit; and a pressing member mounted on the main body so as to press the compressible member from the outside. The tube-side end of the compressible member is pressed against the pressing member. And displaced inward while being displaced inward by the compression of the tube so as to come into contact with the tube in a retaining state, and the blocking means is provided in the hole so as to abut against the outer periphery of the distal end surface of the tube. A projection projecting from a peripheral wall, wherein the projection is formed in the pipe in the retaining state. Plastic deformation to the prevent the are released contact with each may be one to be "released when the acting force becomes the predetermined value or more toward the.

In this case, when the tube is inserted into the hole, the protrusion comes into contact with the outer peripheral portion of the distal end surface of the tube. This abutment prevents more than a predetermined insertion of the tube. In this state, when the compressible member is pressed in the axial direction by the pressing of the pressing member, the tube-side end of the compressible member is displaced inward while being displaced inwardly with respect to the tube. Touch the retaining state. When the contact state is reached,
The tube produces an inwardly acting force. Then, the protruding portion is plastically deformed when the acting force is equal to or more than the predetermined value, and the contact state is released. That is, the inhibition is released.

According to a fourth aspect of the present invention, the projection may include an annular projection projecting from the peripheral wall over the entire circumference. As in the invention of claim 5, the "compressible member may include a compressible ring having a V-shaped cross section that is convex on the inner peripheral side." Also, a tapered ring whose diameter gradually increases inward or a bellows-shaped ring may be used. Furthermore, it may not be annular.

According to a sixth aspect of the present invention, "the compressible ring is formed such that an inner peripheral portion of the compressible ring bites into the tube due to the compression, and a constituent wall of the tube is protruded toward the inner peripheral side over substantially the entire circumference. Plastic deformation ". Further, it may be one that bites into the outer peripheral surface of the tube but does not plastically deform the constituent wall to the inner peripheral side, or may be one that is pressed without being bitten. According to a seventh aspect of the present invention, "the hole has a first hole which is open to the outside of the main body, and a first hole which is smaller in diameter than the first hole which is continuous inward of the first hole. A second hole, wherein the compressible member is disposed in the first hole, and the movement preventing means is formed on a peripheral wall of the hole, and the first hole, the second hole, And the pressing member includes a screw cylinder screwed into the main body in an inserted state with respect to the first hole and through which the tube is inserted.

In this case, the shrinkable member is compressed between the screw cylinder and the boundary end surface by tightening the screw cylinder. According to the invention as set forth in claim 8, the "screw cylinder further comprises a synthetic resin annular plate mounted in a region facing the shrinkable member at an inner end portion of the screw cylinder". The annular plate attached to the contact member comes into contact with the compressible member.

[0018]

As described above, according to the first aspect of the present invention, when the tube is inserted into the hole of the main body, the insertion of a predetermined amount or more is prevented by the ring as the blocking means. . Thereby, the insertion position of the tube is determined. Further, since the insertion is prevented until the compressible member comes into contact with the pipe in a retaining state and the acting force is equal to or more than the predetermined value, the conventional insertion of FIG. The movement of the tube is suppressed as compared with the case. Therefore, the positioning performance of the tube is improved as compared with the conventional one.

When the acting force is equal to or greater than a predetermined value, the inhibition is stably released due to the relationship between the step portion and the ring body. Required force does not increase. Therefore, the force required for the compression, that is, the force required for fixing the pipe, is significantly reduced as compared with that of the above-described FIG.

According to the second aspect of the present invention, since the ring body has the notch, the diameter of the ring body can be reduced smoothly. According to the third aspect of the present invention, when the tube is inserted into the hole of the main body, the insertion of a predetermined amount or more is prevented by the protruding portion serving as the blocking means.
Thereby, the insertion position of the tube is determined. Further, since the insertion is prevented until the compressible member comes into contact with the pipe in a retaining state and the acting force is equal to or more than the predetermined value, the conventional insertion of FIG. The movement of the tube is suppressed as compared with the case. Therefore, the positioning performance of the tube is improved as compared with the conventional one. Further, when the acting force is equal to or more than a predetermined value, the inhibition is stably released by plastic deformation of the protruding portion. Therefore, the force required for the compression after the acting force is equal to or more than the predetermined value does not increase. Therefore, the force required for the compression, that is, the force required for fixing the pipe, is significantly reduced as compared with that of the above-described FIG. And since it is blocked by the protruding portion, the structure for the blocking is simplified. In the invention according to claim 6, the inner peripheral portion of the shrinkable ring cuts into the tube and plastically deforms the constituent wall of the tube to the inner peripheral side over substantially the entire circumference. The inward acting force generated in the tube due to the bite increases. Therefore, the effect of reducing the force required for connecting the pipes is particularly remarkable.

According to the seventh aspect of the present invention, the compressible member is compressed between the screw cylinder and the boundary end face by tightening the screw cylinder, so that the configuration for the compression is simplified. In the invention according to claim 8, since the annular plate made of synthetic resin attached to the screw cylinder comes into contact with the compressible member, it is smaller than that in which the screw cylinder and the compressible member directly contact. The frictional resistance during rotation of the screw cylinder is reduced, and the force required for tightening the screw cylinder is reduced.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. FIG. 1 is a partially cutaway sectional view of a pipe joint (100) according to an embodiment of the present invention. FIG. 2 is a partially cutaway sectional view of the pipe joint (100) of FIG. 1 with the pipe (P) inserted therein, and FIG. 3 is a sectional view of the pipe joint (100) of FIG. FIG. 4 is a cross-sectional view of a partially cut-away state of the screw cylinder (2) in the process of being tightened. FIG.
FIG. 6 is a partially cutaway sectional view showing a state where the screw cylinder (2) is completely tightened in FIG. FIG. 5 is a perspective view of the ring body (5) of FIG. 1, and FIG. 6 is a sectional view taken along the line VI-VI of the pipe joint (100) of FIG.

As shown in FIGS. 1 and 2, the pipe connecting device of this embodiment comprises a metal pipe (P) to be connected,
And a pipe joint (100) to which the pipe (P) is connected. The pipe joint (100) has a cylindrical main body (1) having an inner peripheral hole (1a) into which a pipe (P) is inserted, and a main body (1) inserted into the inner peripheral hole (1a). 1) and a screw cylinder (2) into which the pipe (P) is inserted, and a pipe (P) arranged in the inner peripheral hole (1a) and connected to the main body.
(1) A shrinkable ring (3) for fixing to
(a) an annular packing (4) for ensuring airtightness between the pipe (P) and the main body (1), and the inserted pipe (P)
And a ring body (5) for determining the insertion position of the ring. Note that a relatively thin copper pipe is used as the pipe (P).

[Regarding the Configuration of Each Part] * Main part (1) * The main part (1) has a hexagonal part on the outer periphery.
It is configured to include a cylindrical portion (15) and a second cylindrical portion (16) that is axially continuous with the first cylindrical portion (15) and has a thread formed on the outer peripheral surface.

The inner peripheral hole (1a) extends from the edge of the main body (1) on the side of the first cylinder (15) toward the inside (the second cylinder (16)).
Side), a first hole (11) formed in a certain range of
A second hole (12) formed in a range continuing to the hole (11) up to the edge on the side of the second cylindrical portion (16) and having a smaller diameter than the first hole (11);
It is a structure provided with. A female screw portion (111) for screwing a screw tube (2) described later is formed in a certain range from the outer edge of the first hole portion (11). Also, this female thread (1
Inside 11), there is formed a tapered hole (112) whose diameter gradually decreases inward.

The boundary end face (1) between the first hole (11) and the second hole (12) is an annular plane perpendicular to the axis.
3) is formed. The boundary end face (13) is set to have a size such that an inner end of a shrinkable ring (3) described later abuts. The second hole portion (12) is formed with an enlarged hole portion (14) having a larger diameter than the inside in a certain range inward from the boundary end face (13). The inner side portion of the peripheral wall of the enlarged hole (14) is a tapered wall portion whose diameter gradually decreases inward.
(141).

A tapered step portion (122) whose diameter gradually decreases inward is located at a position inside the second hole portion (12) within a predetermined distance from the enlarged hole portion (14). Are formed. The diameter of the inner edge of the step (122) is set to be larger than the inner diameter of the pipe (P) and smaller than the outer diameter of the pipe (P). * Screw cylinder (2) * The above-mentioned screw cylinder (2) is a ring-shaped hexagonal head (3) which is compatible with a tightening tool (not shown) such as a spanner and is located outside the first cylinder portion (15). 23) and a screw body (22) which is axially continuous with the hexagonal head (23) and is screwed with the female screw (111).
And a pressure cylinder (21) that is continuous with the hexagonal head (23) of the screw body (22) and that presses a shrinkable ring (3) described later. It is a configuration to do. In addition, this screw cylinder
The inner peripheral surface of (2) is set to have a uniform size in the axial direction, and its diameter is set slightly larger than the outer diameter of the pipe (P).

An annular cutout (210) is formed on the outer peripheral portion of the distal end surface of the pressurizing cylinder (21). An annular plate (7) having a rectangular cross section and made of synthetic resin is just fitted into the annular notch (210). This annular plate
As (7), a material such as polyacetal resin having relatively small frictional resistance on the surface is used. Further, on the inner peripheral surface of the hexagonal head (23), there is formed an annular groove portion (230) having a rectangular cross section which is depressed over the entire periphery. This annular groove (23
0) is fitted with a claw ring (6) which is formed in a tapered shape whose diameter gradually decreases inward and has a plurality of claws (not shown) projecting from the inner peripheral edge. This ring with nail
(6) is set to a size such that the claw is pressed against the pipe (P) inserted into the screw cylinder (2) and the inner peripheral hole (1a).

* Shrinkable Ring (3) * The above-described shrinkable ring (3) is a metal annular body formed in a V-shaped cross section that is convex on the inner peripheral side, and is compressed by a force applied in the axial direction. It is configured to be. Also, this shrinkable ring
(3) is disposed substantially coaxially in the tapered hole (112). The shrinkable ring (3) is set so that the inner diameter in the uncompressed free state is slightly larger than the outer diameter of the pipe (P). In addition, the width in the radial direction in the compression completed state where the compression is completed, the boundary end face (13)
Is set to be larger than the radial distance between the outer peripheral edge of the pipe and the pipe (P) inserted into the inner peripheral hole (1a).

The shrinkable ring (3) is made of steel. * Annular packing (4) * The above-mentioned annular packing (4) is a rubber-made annular body with a substantially rectangular cross section. The annular packing (4) is disposed in the enlarged hole (14), and the outer side portion of the annular packing (4) is located outside the boundary end surface (13). . In this arrangement, the inner diameter is slightly larger than the outer diameter of the pipe (P), and it is deformed by the pressure from the shrinkable ring (3) to form an entire circumference with respect to the pipe (P). The shape and size of the annular packing (4) are set so as to be in close contact with each other.

* Ring body (5) * The above-mentioned ring body (5) has a stepped portion (12) in the second hole (12).
2) is disposed on the side of the enlarged hole (14). As shown in FIGS. 5 and 6, the ring body (5) is an annular body having a rectangular cross section and made of synthetic resin, and the outer diameter of the ring body (5) is outside the pipe (P). The second hole (12) having a diameter larger than the diameter
The size is set to be substantially in contact with the outer peripheral wall of the step portion (122) over the entire circumference. Also this ring body
The inner diameter of (5) is set smaller than the inner diameter of the pipe (P).

The ring body (5) is formed with a notch (51) that is cut off in the axial direction at a part in the circumferential direction. The notch (51) has a stepped outer peripheral surface of the ring body (5).
The ring body (5) is set to have a diameter that can be reduced in diameter so as to substantially coincide with the inner edge of (122). Further, since the ring body (5) is set in the above-described dimensional relationship with respect to the pipe (P), the pipe is attached to the ring body (5) regardless of the contracted state or the non-reduced state. (P) abuts in the axial direction.

[Connection of Pipe (P) to Pipe Fitting (100)] To connect the pipe (P) to the pipe fitting (100), first connect the pipe (P) to the screw cylinder (2). Insert from outside. Then, the pipe (P) reaches the second hole (12) of the inner peripheral hole (1a), and as shown in FIG.
Contact (5). The ring body (5) comes into contact with the end of the step (122) on the side of the enlarged hole (14). These abutments prevent the insertion of the tube (P) beyond a predetermined amount. As a result, the insertion position of the pipe (P) is determined, and the pipe (P) is
Positioned with respect to (1).

In this state, the screw cylinder (2) is tightened. Then, the screw cylinder (2) moves inward of the main body (1), and the pressurized cylinder (21) of the screw cylinder (2) is located between the screw cylinder (2) and the boundary end face (13). (3) Compress in the axial direction. This shrinkable ring (3)
Is formed in a V-shaped cross section that is convex on the inner peripheral side as described above, so that the pair of tapered portions constituting the shrinkable ring (3) are compressed in such a manner as to approach each other. . or,
During the compression, the inner peripheral portion of the shrinkable ring (3) is displaced inward while being displaced inward.

Due to the displacement, as shown in FIG. 3, the inner peripheral portion of the shrinkable ring (3) comes into contact with the pipe (P), and the pipe (P) is accidentally pulled out of the shrinkable ring (3). There will be no retaining state.
When it comes into contact with the retaining state, the inward pressing force of the screw cylinder (2) is transmitted to the pipe (P) via the shrinkable ring (3).
At the beginning of the contact, the acting force generated inwardly toward the pipe (P) is relatively small, and the acting force is a force for maintaining the engagement between the ring body (5) and the step (122). Since it is smaller, the contact state between the ring body (5) and the step (122) is maintained. On the other hand, in this state, since the degree of contact between the inner peripheral portion of the shrinkable ring (3) and the pipe (P) is small, the ring body (5)
The inner circumference of the shrinkable ring (3) slides against the pipe (P) due to the drag acting on the pipe (P) from above and the inward pressing force acting on the shrinkable ring (3). .

Accordingly, the insertion preventing state of the tube (P) is maintained. Then, as the displacement progresses, the inner peripheral portion of the shrinkable ring (3) bites into the component wall of the pipe (P) over the entire periphery, and the degree of contact increases. Further, when the degree of contact becomes larger than a predetermined degree due to the progress of the displacement, the force transmitted from the compressible ring (3) to the pipe (P) becomes larger, and the above-mentioned acting force becomes larger than a predetermined value. At this time, due to the pressing force acting on the ring body (5) from the pipe (P), the ring body (5) exerts a component force of the reaction force received from the inclined surface of the step (122) (the axis of the ring body (5)). Due to the force toward the center, the diameter is reduced and moves toward the inside of the step (122). When the outer diameter of the ring body (5) becomes smaller than the diameter of the inner edge of the step (122), the engagement between the ring body (5) and the step (122) is made as shown in FIG. Comes off, ring body (5)
Moves further inward, and the above-described insertion blocking state is released. In this state, the inner circumference of the shrinkable ring (3) and the pipe
No sliding with (P).

Finally, the outer peripheral ends of the pair of tapered portions come into contact with each other, and the compression and the displacement are completed. At this point, the tube for the body (1)
Fixing of (P) is completed. In this state, the shrinkable ring (3)
Of the pipe (P) penetrates the entire circumference of the pipe (P).
The component wall of (P) is plastically deformed convexly inward.
On the other hand, the compression of the shrinkable ring (3) pushes the annular packing (4) into the enlarged hole (14) over the entire circumference. This push reduces the inner diameter of the annular packing (4),
(P) is adhered over the entire circumference. Also, the tapered wall (1
When the annular packing (4) is pressed against the pipe (41), the inner diameter of the annular packing (4) is reduced, and the annular packing (4) comes into close contact with the pipe (P). This allows
Airtightness between the main body (1) and the pipe (P) is ensured.

Since the hermetic seal is ensured even at the contact portion between the inner peripheral portion of the shrinkable ring (3) and the pipe (P), the hermetic performance of the pipe joint (100) is further improved. In this case, since the ring (5) and the step (122) prevent insertion of the pipe (P) beyond a predetermined amount, the insertion position of the pipe (P) is determined. In addition, until the acting force becomes equal to or more than the predetermined value after the contact with the retaining state at the time of tightening the screw cylinder (2), the inward movement of the pipe (P) is suppressed. Have been. Therefore, the positioning performance of the pipe (P) is improved as compared with the conventional one shown in FIG.

When the acting force exceeds a predetermined value, the insertion blocking state by the step portion (122) and the ring body (5) is released, and the compression after the predetermined value or more is required. Power does not increase. Therefore, the force required for the compression, that is, the force required for connecting the pipes is significantly reduced as compared with the conventional one. In particular, since the inner peripheral portion of the shrinkable ring (3) bites into the pipe (P), the inward acting force generated in the pipe (P) increases, so that the effect of the reduction is remarkable. I have.

Since the insertion blocking state is released by the relationship between the step (122) and the ring body (5), the releasing operation is stable. Further, since the ring body (5) is provided with the notch (51), the diameter of the ring body (5) can be reduced smoothly. Note that the ring body (5) may have no notch (51). The tightening of the screw cylinder (2) compresses the shrinkable ring (3), so that the structure for the compression is simplified.

Since the annular plate (7) comes into contact with the shrinkable ring (3), the screw cylinder (2) is compared with the screw cylinder (2) and the shrinkable ring (3) which are in direct contact. ) Has reduced frictional resistance during rotation. Therefore, the force required for tightening the screw cylinder (2) is reduced. In this case, the above-mentioned pipe (P) corresponds to the “pipe” described in the above-mentioned claims, and the above-mentioned main body (1) corresponds to “the main body” described in the above-mentioned claims. The inner peripheral hole (1a) corresponds to the "hole" described in the claims described above, and the first hole (11) corresponds to the "first hole" described in the claims. Hole, and the second hole described above.
(12) corresponds to the “second hole portion” described in the claims described above, and the boundary end surface (13) is referred to as the “boundary end surface” or the “movement preventing means” described in the claims. Is equivalent to

The screw cylinder (2) corresponds to the "screw cylinder" and "pressing member" described in the claims, and the shrinkable ring (3) corresponds to the claims described in the claims. , "Compressible ring" and "compressible member". Furthermore, the step (1
22) corresponds to the “step portion” described in the appended claims,
The above-mentioned ring body (5) corresponds to the `` ring body '' described in the claims described above, and the notch (51) corresponds to the `` notch '' described in the claims described above, The step (122) and the ring body (5) correspond to the "blocking means" described in the appended claims.

The above-mentioned annular plate (7) corresponds to the "annular plate" described in the appended claims. [Regarding Modification] FIG. 7 is a pipe joint according to another embodiment of the present invention.
It is principal part sectional drawing of (100). The pipe joint (100) shown in the figure has an annular projection (17) projecting from the position inside the enlarged hole (14) in the peripheral wall of the second hole (12) over the entire circumference. It is a configuration provided. The annular convex portion (1
7) is in contact with the outer peripheral portion of the distal end surface of the pipe (P) over the entire circumference, and when the above-mentioned acting force becomes equal to or more than the above-mentioned predetermined value when the compressible ring (3) is compressed. The contact state is set so as to be released by plastic deformation.

In this case, when the pipe (P) is inserted into the inner peripheral hole (1a), the annular convex portion (17) comes into contact with the outer peripheral portion of the distal end surface of the pipe (P). This abutment prevents the tube (P) from being inserted more than a predetermined amount. Then, the annular convex portion (17) is plastically deformed when the acting force becomes equal to or more than the predetermined value, and the contact state is released. That is, the inhibition is released. In this case, the structure is prevented by the annular convex portion (17), so that the structure for the prevention is more simplified than that of the above-described embodiment.

The above-mentioned annular convex portion (17) corresponds to the “annular convex portion” and the “projecting portion” described in the appended claims. still,
The “projection” may be non-annular. . In the above embodiment, the shrinkable ring (3) is formed into an annular body having a V-shaped cross section. Other configurations can be adopted as long as they are displaced inward while being displaced. For example, a tapered ring whose diameter gradually increases inward or a bellows-shaped ring may be used. Furthermore, it may not be annular.

[0046] In the above embodiment, the shrinkable ring (3)
The inner peripheral portion of the pipe (P) penetrates the wall of the pipe (P) over the entire circumference and is plastically deformed convexly to the inner peripheral side. The component wall may not be plastically deformed convexly to the inner peripheral side, or the inner peripheral portion may be pressed against the pipe (P) without biting. In this case, a steel pipe may be used as the pipe (P).

[0047] In the above embodiment, the above-mentioned “movement preventing means” is the boundary end face (13). However, as long as the inward movement of the shrinkable ring (3) is prevented, other means are used. A configuration can be adopted. For example, the inner end of the shrinkable ring (3) may be pivotally supported on the peripheral wall of the first hole (11). . The annular packing (4) may be a rubber ring having a substantially circular cross section, a so-called O-ring, in addition to the rubber ring having a substantially rectangular cross section.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of a pipe joint (100) according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the pipe joint (100) of FIG. 1 with a pipe (P) inserted and partially cut away.

FIG. 3 is a cross-sectional view of a partially cut-away state of the screw cylinder (2) in the pipe joint (100) of FIG.

FIG. 4 is a partially cutaway sectional view of the pipe joint (100) of FIG. 1 in a state where the screw cylinder (2) is completely tightened.

FIG. 5 is a perspective view of the ring body (5) of FIG. 1;

FIG. 6 is a VI-VI sectional view of the pipe joint (100) of FIG. 1;

FIG. 7 shows a pipe joint (10) according to another embodiment of the present invention.
(0) cross section

FIG. 8 is an explanatory view of a conventional pipe connection device.

FIG. 9 is an explanatory view of another pipe connection device.

[Explanation of symbols]

 (P) ・ ・ ・ Tube (1) ・ ・ ・ Main body (1a) ・ ・ ・ Inner peripheral hole (11) ・ ・ ・ First hole (12) ・ ・ ・ Second hole (13) ・ ・ ・Boundary end surface (2) ・ ・ ・ Screw tube (3) ・ ・ ・ Shrinkable ring (122) ・ ・ ・ Step (5) ・ ・ ・ Ring body

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16L 19/08-19/14 F16L 37/10-37/20

Claims (8)

(57) [Claims] 1. A pipe to be connected, a main body having a hole into which the pipe is inserted, and blocking means for abutting against a tip of the inserted pipe to prevent the insertion of a predetermined amount or more, A compressible member arranged on the outer peripheral side of the inserted tube in the hole and compressed by a force applied in an axial direction; and a movement preventing unit for preventing the inward movement of the compressible member; And a pressing member attached to the main body so as to press the compressible member from the outside. The compressible member is configured such that the tube-side end is inwardly compressed by the pressing of the pressing member. Is displaced inward while being displaced, and comes into contact with the pipe in a retaining state. The blocking means is formed on the peripheral wall of the hole and has a tapered shape whose diameter gradually decreases inward. A step, and a ring body interposed between the distal end surface of the tube and the step, When the inward acting force generated in the pipe in the retaining state becomes greater than or equal to a predetermined value, the diameter of the ring body is reduced, and the ring body moves toward the inner side of the stepped portion to prevent the ring. Is released from the pipe connection device. 2. The pipe connection device according to claim 1, wherein the ring body includes a notch formed in a part of a circumferential direction thereof in an axial direction. 3. A pipe to be connected, a main body having a hole into which the pipe is inserted, and blocking means for contacting a tip of the inserted pipe to prevent the insertion beyond a predetermined value. A compressible member arranged on the outer peripheral side of the inserted tube in the hole and compressed by a force applied in an axial direction; and a movement preventing unit for preventing the inward movement of the compressible member; And a pressing member attached to the main body so as to press the compressible member from the outside. The compressible member is configured such that the tube-side end is inwardly compressed by the pressing of the pressing member. The stopper is displaced inward while contacting the tube in a state of being prevented from coming off, and the blocking means projects from the peripheral wall of the hole so as to contact the outer peripheral portion of the distal end surface of the tube. Portion, wherein the protrusion is directed inwardly to the tube in the retaining state. Tube connecting device the utility is plastically deformed by the abutment with said blocking is released is released when it becomes the predetermined value or more. 4. The pipe connection device according to claim 3, wherein the projecting portion includes an annular projecting portion projecting from the peripheral wall over the entire circumference. 5. The pipe connection device according to claim 1, wherein the shrinkable member includes a shrinkable ring having a V-shaped cross section that is convex inward. 6. The shrinkable ring according to claim 5, wherein an inner peripheral portion of the shrinkable ring bites into the tube by the compression, so that a constituent wall of the tube is plastically deformed to an inner peripheral side over substantially the entire circumference. Pipe connection equipment. 7. The first hole portion, which is open to the outside of the main body portion, and the second hole portion, which has a smaller diameter than the first hole portion, is provided on an inner side of the first hole portion. Wherein the shrinkable member is disposed in the first hole, and the movement preventing means is formed on a peripheral wall of the hole and is a boundary end face between the first hole and the second hole. The pipe connection according to any one of claims 1 to 6, wherein the pressing member includes a screw cylinder screwed into the main body in an inserted state with respect to the first hole and through which the pipe is inserted. apparatus. 8. The pipe connection device according to claim 7, further comprising an annular plate made of a synthetic resin, which is mounted on an inner end of the screw cylinder in a region facing the shrinkable member.