JP3096846B1 - Flexible pipe joint - Google Patents

Abstract

Abstract: [Problem] A joint main body (1) and a tightening cylinder screwed into the main body.
(2) The front side is elastically expandable and contractable, and is externally fitted to the front end of the bellows pipe (8) to retain the retainer chamber (17) in the joint main body (1).
With regard to a flexible pipe joint having a metal retainer (3) pushed into the bellows, the sealing property of the bellows pipe (8) to be connected is improved and even if the bellows pipe (8) is pulled carelessly, Make sure that the connection is secure so that it does not come off. An inner diameter of a bite portion (33) at a front end of a retainer (3) in a free state is smaller than an outer diameter of a peak portion (81) of a bellows tube (8) and is smaller than that of a valley portion (82). The retainer storage chamber (17) is formed in a cylindrical shape, and the inner diameter of the cylinder is capable of storing the retainer (3) substantially in the free state, and prevents the front end from expanding. The size must be set so that it fits externally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible pipe joint, and more particularly to a flexible pipe joint to which a flexible metal bellows pipe is connected.

[0002]

2. Description of the Related Art As a flexible pipe joint, Japanese Utility Model Publication No. Hei 7-2846.
No. 7 discloses a technique disclosed in Japanese Patent Application Laid-Open No. H07-139,873. As shown in FIG. 7, this flexible pipe joint has a cylindrical joint main body (5) having a tapered inner peripheral surface (50), and is screwed into a rear portion (left end in the drawing) of the joint main body (5). And an annular retainer (52) pushed into the tapered inner peripheral surface (50) of the joint main body (5) by tightening the nut (51). 7 is a cross-sectional view before the nut (51) is tightened, and the upper half is a cross-sectional view when the nut (51) is completely tightened.

A bellows tube (54) is inserted into a nut (5)
Insert from the back of 1) and insert the insertion end into the joint main body (5)
Pipe receiving surface (55) located ahead of the tapered inner peripheral surface (50)
Contact. Since the minimum diameter of the nut (51) and the bellows tube (54) is set to be larger than the outer diameter of the peak of the bellows tube (54), the bellows tube (54) is easily inserted into the flexible fitting. Can be done.

In this state, the nut (51) is tightened. Then, as shown in the upper half of FIG.
It is pushed by (51) and moved forward (to the right in the drawing) of the joint main body (5), and is pushed into the tapered inner peripheral surface (50). Since the retainer (52) is formed into an annular body having a plurality of slits formed in the circumferential direction from the front end side, the retainer (52) is pushed into the tapered inner peripheral surface (50), The diameter is reduced from the front end side along the tapered inner peripheral surface (50), and the bite portion (53) provided at the front end portion of the retainer (52) (referred to as “flange” in the same publication) is formed. , So as to bite into a valley at a predetermined position of the bellows tube (54). By further tightening the nut (51), the inner peripheral surface of the taper
A bellows tube (54) inserted forward of the bite portion (53) of (50)
The insertion end of the front end of the biting portion (53) and the pipe receiving surface
(55), whereby the connection of the bellows tube (54) is completed.

[0005]

In this conventional device,
The bellows pipe (54) is inserted into the flexible pipe joint in which the joint main body (5), the nut (51) and the retainer (52) are pre-assembled, and the nut (51) is simply tightened. Since the connection of ()) is completed, the connection work is easy, the time required for the connection work is shortened, and the parts are not forgotten.

However, the retainer (52) is mainly connected to the joint.
By pressing the tapered inner peripheral surface (50) of (5), the retainer (52) is deformed into a form that fits exactly to the tapered inner peripheral surface (50), as shown in the upper half of FIG. Let me
In addition, the flat surface on the front of the biting portion (53) is
It is actually difficult to act straight on 5).

[0007] Regardless of whether the retainer (52) is made of metal or resin, a predetermined range of the insertion end of the bellows pipe (54) is covered by the pipe receiving surface (5).
When the retainer (52) made of such a hard member is pushed into a tapered tubular portion such as the tapered inner peripheral surface (50), the retainer (52) made of such a hard member must follow the taper. The shape is rarely deformed.
As shown in (5), the retainer (52) bends and deforms inward beyond the taper angle of the tapered inner peripheral surface (50). Along with this,
A gap is formed between the outer peripheral surface of the retainer (52) and the tapered inner peripheral surface (50), and the bite portion (53) is fitted into the valley portion of the bellows pipe (54) in an obliquely distorted posture. Becomes If the nut (51) is tightened while it is obliquely fitted, the tightening force will not act uniformly on the bellows pipe (54) from the bite part (53), and the front part of the bite part (53) will not work. Presses the bellows tube (54) located ahead of the biting portion (53) against the tube receiving surface (55) with uneven force. Accordingly, the bellows pipe (54) is pressed obliquely against the pipe receiving surface (55), and it is difficult to obtain a reliable connection state.

The tightening force of the nut (51) is once received by the tapered inner peripheral surface (50) and partially acts as a force to bend the retainer (52). Bellows tube (54)
The conversion efficiency for converting the pressure into a pressing force pressing the tube receiving surface (55) is poor.

As described above, in this conventional apparatus, a bellows tube
(54) is pressed by a non-uniform force by the biting portion (53) of the retainer (52) which is located obliquely distorted with respect to the pipe receiving surface (55), and the tightening force of the nut (51) is reduced. All pipe receiving surfaces (5
Since it is difficult to act as a pressing force for pressing 5), the sealing property of the bellows tube (54) in the connected state is poor,
If the bellows tube (54) is accidentally pulled,
There is a problem that the bellows tube (54) comes off without the front surface of the (52) being able to hold down the bellows tube (54).

[0010] The present invention relates to a tubular joint main body, a tightening tube screwed into the joint main body from behind, and a bellows tube located in front of the tightening tube and inserted from the rear. An annular retainer which is pushed into a retainer housing chamber in the joint main body while being fitted, wherein the retainer has a plurality of arc-shaped cross-sections which are located side by side in the circumferential direction through slits cut from a front end. It is composed of a metal split member,
Each of the divided members is connected to each other at a thin portion at a rear end, and the front end of the retainer is elastically expandable and contractable with the thin portion as a fulcrum, and the front end of each of the divided members is In the inside of the flexible pipe joint which is formed with a biting portion that cuts into the valley of the bellows pipe, the sealing property of the connected bellows pipe is improved, and the bellows pipe is inadvertently pulled. Another object of the present invention is to provide a flexible pipe joint which can be securely connected without easily coming off. <1>

[0011]

In order to solve the above-mentioned problem, the solution of the present invention is as follows: "The inner diameter of the bite portion of the retainer in the free state is equal to the outer diameter of the peak portion of the bellows tube. The retainer chamber is formed in a cylindrical shape, and the inner diameter of the cylinder is such that the retainer can be accommodated in the substantially free state and the front end thereof Is set to a size that can be fitted to the outside in the unfolded state, an annular concave portion is formed on the outer periphery of each of the divided members, and is formed separately from the divided member in the annular concave portion and faces rearward from the front end. A cylindrical member made of an elastic synthetic resin or rubber having a plurality of grooves formed therein is housed in an externally fitted state, and a flange portion made of the same material as the cylindrical member is integrally formed on the rear end of the cylindrical member. Inner wall of the joint main body The flange portion is provided with an annular engaging projection projecting from behind, the front end face of the tightening cylinder is provided with two concentric annular end faces, and the outer annular end face on the outer peripheral side is the inner annular end face. The pressing end surface is located at a position advanced forward from the inner circumferential end surface on the peripheral side, and the rear end surface of the tubular member is a pressure receiving end surface located on the outer peripheral side and forward of the rear end of the retainer, When tightening the tightening cylinder,
The pressing end face of the tightening cylinder is set to abut against the pressure receiving end face of the cylindrical member, and the inner annular end face of the tightening cylinder is set to face the rear end of the retainer via a slight gap. I did. "

The above-mentioned solution works as follows. The retainer is housed in the joint main body from the rear, and the fastening tube is further screwed into the rear end of the joint main body from the rear to mount the flexible pipe joint. A bellows tube as a flexible tube is inserted into the thus assembled flexible tube joint from behind the tightening cylinder. The inner diameter of the bite portion provided so as to protrude inside the front end of the retainer in a free state is set smaller than the outer diameter of the peak portion of the bellows tube and larger than the valley portion. When inserted, the foremost ridge will come into contact with the inner end of the bite, but the retainer is
Since it is constituted by a plurality of divided members arranged in parallel via a slit and can be expanded with the thin portion at the rear end as a fulcrum, when the bellows tube is forcibly pushed in, the peak portion of the bellows tube is Then, while forcibly increasing the diameter of the bite portion of the retainer, the bite is passed through the bite portion and inserted into the front of the retainer, and the inserted end thereof comes into contact with the pipe receiving surface mainly of the joint.

Each of the divided members opened from the front end is returned to the initial state, so that the biting portion bites into a valley following the peak of the bellows tube. When the tightening cylinder is further tightened in this state, the retainer is pushed forward by the tightening cylinder, and while pushing the bellows tube located forward of the front portion of the bite portion into the retainer housing chamber in the joint main body. It will be pushed in.

The retainer storage chamber is formed in a cylindrical shape, and the inner diameter of the cylinder is capable of storing the retainer in a substantially free state. While being substantially kept in the free state posture that bites into the part, it is pushed straight into the retainer storage chamber, and its front end is held in the expansion preventing state by the inner peripheral surface of the retainer storage chamber. Become.

In other words, the divided members constituting the retainer do not bend or deform when being housed in the retainer housing chamber, and the biting portion formed at the front end thereof has a bellows shape. It does not fit unevenly into the valley of the tube in an obliquely distorted posture and does not press the bellows tube unevenly.
In particular, since a cylindrical member provided separately from the split member of the retainer is externally fitted to the split member of the retainer, the retainer allows the metal split member and the elastic synthetic resin or rubber cylindrical member to relatively rotate. It will be of a configuration that is integrally assembled. As described above, when the retainer having the configuration in which the cylindrical member made of the elastic material is fitted to the outside is accommodated in the joint main body from the rear, the flange integrally provided at the rear end of the cylindrical member has the inside of the joint main body. An annular engaging projection projecting from the peripheral wall is brought into contact with and engaged from the rear side. Then, when the tightening cylinder is tightened, the pressing end surface of the tightening cylinder comes into contact with the pressure receiving end surface of the cylindrical member. This state is a state in which the tightening cylinder is temporarily fixed at the initial position. still,
A plurality of grooves are formed in the axial direction from the front end side of the cylindrical member, and the groove forming area of the peripheral wall of the cylindrical member is thin. Thereby, the diameter of the front end side of the cylindrical member can be forcibly expanded. Therefore, when the bellows tube is inserted into the flexible pipe joint assembled in this manner, the foremost ridge of the bellows tube comes into contact with the bite portion of each divided member. Since the members can also be expanded from their front ends, the front end of each divided member can be expanded with the thin portion at the rear end as a fulcrum. You can pass between. Each of the divided members opened from the front end is returned to the initial state by the elastic return force of the tubular member, and the front end of the divided member cuts into a valley following the peak of the bellows tube. Become. That is, the cylindrical member functions as an elastic ring for tightening the divided member from the outside. When the tightening cylinder is further tightened in this state, the pressing end surface of the tightening cylinder presses the pressure receiving end surface of the cylindrical member. Accordingly, the flange portion engaged with the engagement convex portion is bent rearward until its outer diameter becomes smaller than the inner diameter of the engagement convex portion, and the tubular member is moved forward in the annular concave portion. Is pushed to. The cylindrical member is reduced in axial length by being pressed between the front wall of the annular concave portion and the pressing end surface, and is deformed so as to protrude laterally (outward). Due to this deformation, the outer diameter of the tubular member rises beyond the outer diameter of the retainer, and in this state, the tubular member is pushed into the retainer chamber together with the tubular member. The cylindrical member deformed so as to be raised to the outside beyond the outer diameter of the retainer is accommodated in the retainer accommodating chamber together with the retainer, thereby being absorbed between the retainer and the inner peripheral surface of the retainer accommodating chamber. Is more reliably prevented from coming out of the retainer storage chamber.
Thus, the bellows tube pinched between the retainer and the tube receiving surface is reliably prevented from falling off.

[0016]

According to the present invention, when the retainer is pushed into the retainer chamber, each of the divided members hardly bends or deforms. The part can efficiently convert to a pressing force for pressing the bellows tube, and a large pressing force can be expected. Also, since the front portion of the bite portion is hardly fitted into the valley portion of the bellows tube in a distorted posture, the pressing force is applied to the bellows tube inserted forward from the front portion of the bite portion. On the other hand, the force can be reliably applied as a force that is applied in the correct direction and uniformly, so that the flattening of the bellows tube in the retainer accommodating chamber is ensured. Therefore, the bellows tube is connected in a retaining state in a state of being securely sealed.

Further, since the inner diameter of the retainer storage chamber is set to a size for holding the retainer in the expansion preventing state, even if the bellows tube in the connected state is pulled, the front end of the retainer expands. Therefore, the peak of the bellows tube located forward of the front end of the retainer cannot exceed the bite portion. Therefore, there is no inconvenience that the bellows tube is accidentally dropped.

<2> In the invention described in the above item 1, the pipe receiving surface with which the insertion end of the bellows tube abuts is provided ahead of the retainer storage chamber, and outside the pipe receiving surface, An annular groove into which an O-ring is loaded is formed, and when the retainer is pushed to the final position in the retainer storage chamber, the front portion of the retainer stops the O-ring in the annular groove at the same time as this. The front portion of the biting portion is set so as to press the outer peripheral area of the insertion end of the bellows tube against the outer edge of the tube receiving surface. '' The front surface of the split member presses the O-ring in a retaining state, and at the same time, the front surface of the bite portion forms an outer peripheral area of a mountain portion which is an insertion end of a bellows tube. The outer edge of the tube receiving surface, i.e. It is pressed against the terminal edge of the surface and the annular groove. As a result, the peaks of the bellows tube are crushed by the pressing of the bite portion at the portions corresponding to the boundary edges, and the portions projecting outside the boundary edges are pushed into the annular groove to be divided. O depending on the front part of the member
It will be pressed by the ring. Therefore, the bellows tube is more reliably connected in the retaining state, and the sealing property is improved.

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

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 an exploded perspective view of a partially cutaway portion of a flexible pipe joint according to an embodiment of the present invention.
FIG. 2 is a partial sectional view showing a state in which a bellows pipe (8) is inserted into the flexible pipe joint.

As shown in FIG. 1, the flexible pipe joint according to this embodiment has a cylindrical joint main body (1), a retainer (3) inserted into the joint main body (1), and a retainer (3). (3) and a tightening cylinder (2) for pushing the inside of the joint main body (1). In addition, these joint main body (1), tightening cylinder (2) and retainer
(3) is made of a metal material such as brass.

First, the joint main body (1) will be described. As shown in FIGS. 1 and 2, the above-mentioned joint main body (1) is provided on the outer periphery of the front end (the upper end in FIG. 1, the left side in FIG. 2) of the joint main body (1), for example, at the gas inlet of the gas cock. A male screw (10) for screw connection is engraved.

A female screw (13) is formed on the inner periphery of the rear end of the joint main body (1), which is the screw-in side end of the tightening cylinder (2) described later. In the joint main body (1), an engagement projection (11) is formed in an annular shape over the entire inner circumference in front of the female screw (13). In front of the engaging projection (11), a retainer expansion allowance (1
2) Following the corner radius, a cylindrical retainer storage chamber
(17) is formed.

Further, a gas passage (18) having a small diameter is formed further forward of the retainer storage chamber (17), and a rear end of the gas passage (18) and a front end of the retainer storage chamber (17) are formed. An annular pipe receiving surface (15) is formed so as to be positioned at right angles to the inner peripheral surface of the retainer storage chamber (17) between the side end portion. An annular groove (19) is formed outside the tube receiving surface (15), and an O-ring (14) for ensuring airtightness with the bellows tube (8) is formed in the annular groove (19). Is loaded.

Next, the tightening cylinder (2) will be described. As shown in FIGS. 1 and 2, the tightening cylinder (2) is composed of a hexagonal spanner engaging portion (22) and a cylindrical portion (23) following the wrench engaging portion.

On the outer periphery of the cylindrical portion (23) in the middle of the axial direction,
A male screw (29) screwed into the female screw (13) of the joint main body (1) is engraved, and the front end face of the cylindrical portion (23) has two annular end faces formed concentrically. It has become.

The outer annular end surface on the outer peripheral side is a pressing end surface (25).
And protrudes forward from the inner annular end surface (28) on the inner peripheral side. Then, the pressing end face in the cylindrical portion (23)
The cylindrical portion from (25) to the male screw (29) is set to a size that can be inserted into the above-mentioned engaging projection (11).

Further, a concave portion (24) extending over the entire periphery is formed on the inner periphery of the spanner engaging portion (22).
(24) is loaded with an annular packing (27). The annular packing (27) is for preventing rainwater or the like from entering the flexible pipe joint by coming into contact with a synthetic resin covering pipe (80) covering the outer periphery of the bellows pipe (8). is there.

Finally, the retainer (3) will be described.
As shown in FIG. 3, the retainer (3) is formed in a cylindrical shape as a whole, and is accommodated in the joint main body (1) so as to be located in front of the tightening cylinder (2).

The retainer (3) is cut in the axial direction from the front end so that a thin portion (31) is formed on the annular end surface (30) at the rear end on the side of the tightening cylinder (2). The four slits (32) are provided at a pitch of 90 degrees in the circumferential direction, whereby the retainer (3) has a configuration having four divided members (37). The front end side is easily bent so as to expand or contract easily.

The front part (34) of the dividing member (37) has a flat surface, the outer peripheral edge of which is formed in an arc-shaped cross section, and the front end side of the dividing member (37) is formed by a slit. (32)
The outer diameter of the front end of the retainer (3) in a state reduced in diameter by the same amount as the inner diameter of the retainer storage chamber (17),
It is assumed that the width of the slit (32) is set.

On the outer peripheral side of each of the divided members (37), an annular concave portion (36) having a predetermined width is formed so as to be continuous in the circumferential direction of the retainer (3). An annular biting portion (33) is formed inside the front end portion of the dividing member (37) so as to be continuous with the front surface portion (34), and the inner diameter of the biting portion (33) is the same as that of the retainer (3). ) Is a bellows tube in a free state where the diameter on the tip side does not expand or contract
The diameter of the crest (81) of (8) is smaller than the diameter of the bellows tube (8).
The dimensions are set to be slightly larger than the diameter of (82).

Then, the annular concave portion (36) of the retainer (3)
A cylindrical member made of an elastic synthetic resin as shown in FIG.
(40) is externally fitted. The cylindrical member (40) has a cylindrical body (4) provided with a plurality of grooves (42) in the axial direction from the front end side on the outer peripheral surface thereof.
1) An annular cylinder having a configuration in which an annular body (43) is connected to a rear end portion. A portion of the peripheral wall of the tubular body (41) where the groove (42) is formed is a thin portion.

The inner diameter of the cylindrical member (40) is set so as to substantially match the outer diameter of the annular concave portion (36) formed in the retainer (3), and as shown in FIG. Only the body (41) is housed and mounted in the annular recess (36) of the retainer (3). The axial length of the cylindrical body (41) is the same as that of the annular recess.
It is set to be slightly shorter than that of (36).

The rear end surface of the annular body (43) is a pressure receiving end surface (45) pressed against the pressing end surface (25) of the tightening cylinder (2), and is provided on the outer peripheral side of the pressure receiving end surface (45). Is an annular flange (44)
Are integrally formed so as to project outward. The outer diameter of the flange portion (44) is set to be larger than the inner diameter of the engagement protrusion (11).

The distance from the pressing end face (25) of the tightening cylinder (2) to the annular end face (28) is from the pressure receiving end face (45) of the cylindrical member (40) to the thin portion (3) of the retainer (3). The distance is set to be larger than the distance to the annular end face (30) in which 31) are arranged. Thus, a predetermined gap (S) is formed between the annular end face (30) and the annular end face (28) in a state where the pressing end face (25) is in contact with the pressure receiving end face (45). .

The procedure for assembling the flexible pipe joint will be described. First, the cylinder member (40) is divided into the retainer (3) divided members (3
Externally fit to 7) to integrate them. Since the entire cylindrical member (40) is molded of elastic synthetic resin,
Of (3), the annular end face (30) on the rear end side with a small outer diameter
The front end side of the tubular body (41) of the tubular member (40) is elastically deformed in the expanding direction by using the annular body (43) as a fulcrum by forcibly fitting the tubular body (40) against the front end of the tubular member (40). And the cylindrical member
(40) can be externally fitted to the dividing member (37). And when the cylindrical body (41) corresponds to the annular concave portion (36), the cylindrical body
(41) is elastically restored, and the tubular body (41) is housed in the annular concave portion (36) in an externally fitted state.

After assembling the retainer (3) and the synthetic resin tubular member (40), the retainer (3) is placed from the rear (right side in FIG. 2) of the joint main body (1), and the annular end face (30) is placed rearward. Insert in the end position. As a result of the insertion of the retainer (3), the flange portion (44) formed on the tubular member (40) is brought into a state of being engaged with the engaging convex portion (11) of the joint main body (1) from the rear side. The retainer (3) is positioned coaxially with the joint main body (1).

Thereafter, the male screw (29) of the tightening cylinder (2) is screwed into the female screw (13) of the joint main body (1), and the pressing end face (25) of the tightening cylinder (2) is pressed against the pressure receiving end face. When it comes into contact with (45), the tightening cylinder (2) is attached to the initial position.

In this state, the front end of the retainer (3) is set so as to be located at the retainer expansion allowing portion (12) of the joint main body (1), and the front end portion of the retainer (3) is in contact with the bite portion (33) of the retainer (3). The distance (L) between the opposed pipe receiving surface (15) is
(8) The configuration is approximately the same as the size of one peak.
Also, at this time, the flange portion (44) of the tubular member (40) is sandwiched between the engaging convex portion (11) of the joint main body (1) and the pressing end surface (25) of the tightening barrel (2). However, no force acts on the retainer (3) to prevent the bite portion (33) from expanding.

Next, a bellows pipe (8), which is a flexible pipe, is inserted into the flexible pipe joint from behind the tightening cylinder (2). Then, as shown by the solid line in FIG. 2, the foremost peak (81) of the bellows tube (8) comes into contact with the bite portion (33) of the retainer (3).

When the bellows tube (8) is further pushed in from the contact state, the peak portion (81) pushes the bite portion (33) to the outer peripheral side. At this time, the retainer (3) and the cylindrical member fitted around the retainer (3)
In (40), the slit (32) and the groove (42) are respectively formed as described above, and these front ends are
The front end side of the retainer (3) can be expanded because it is located at the retainer expansion allowable portion (12) of the joint main body (1). As a result, as shown by the broken line in FIG.
(33), the retainer (3) returns to the above-mentioned free state by the elastic return force of the tubular member (40), and the bite portion (33)
Penetrates into the valley (82) following the mountain (81).

In this state, the engagement convex portion (11) and the flange portion
(44) and the end face of the biting portion (33) and the pipe receiving surface (1
Since the distance (L) to 5) is set to one peak of the bellows tube (8), only the foremost peak (81) of the bellows tube (8) is set as shown by the broken line in FIG. Is projected forward from the retainer (3).

When the tightening cylinder (2) is further tightened in this state, the pressing end face (25) of the tightening cylinder (2) comes into contact with the pressure receiving end face (45) of the cylindrical member (40), and the annular shape is formed. The cylindrical member (40) housed in the recess (36) is connected to the annular end face (30) of the retainer (3) and the tightening cylinder.
It is pushed forward by the gap (S) between the annular end face (28) of (2). Since the cylindrical member (40) is molded from an elastic synthetic resin, the cylindrical member (40) is pushed forward by the pressing end surface (25), thereby causing the annular concave portion (3) as shown by the two-dot chain line in FIG.
At the same time, the gap (S) disappears and the inner annular end face (28) comes into contact with the annular end face (30). After that, tighten the cylinder (2) with the metal retainer.
The annular end face (30) at the rear end of (3) is pressed.

The pressing end surface (25) of the tightening cylinder (2) is a cylindrical member.
When pressing the pressure receiving end surface (45) of the (40), the movement of the tubular member (40) is prevented by the engagement of the engagement convex portion (11) and the flange portion (44). )
The base end side of the flange portion (44) is forcibly moved to the front end relative to the engagement convex portion (11), and accordingly, the flange portion (44)
Is bent rearward. Flange (44)
Is formed of an elastic synthetic resin similarly to the cylindrical member (40), the flange portion (44) is easily bent rearward. When the outer diameter of the flange portion (44) becomes smaller than the inner diameter of the engaging convex portion (11), the engagement between the flange portion (44) and the engaging convex portion (11) is released, and the retainer is removed.
(3) is directly pressed by the tightening cylinder (2) and pushed into the retainer storage chamber (17) as shown in FIG.

The retainer storage chamber (17) is formed in a cylindrical shape, and the inner diameter thereof is set between the slits (32) between the divided members (37).
The outer diameter of the retainer (3) in the state reduced in diameter by the distance is set to substantially match the outer diameter of the front end of the retainer (3), and
Since the outer peripheral edge of the front end of (7) is formed in an arc shape in cross section, the retainer is tightened by tightening the tightening cylinder (2).
(3) is pushed by the tightening cylinder (2), and the diameter of the front end is reduced while the bite portion (33) is still fitted to the valley (82) of the bellows tube (8). While being forcibly pushed into the retainer storage chamber (17), the retainer (3) is moved into the retainer storage chamber (17).
Is held in the expansion-prevented state by the inner peripheral wall.

In this case, the outer diameter of the front end of the retainer (3) in a free state and the outer diameter of the front end of the retainer (3) in a state reduced in diameter by the slit (32). It is assumed that the width of the slit (32) is set to be small so as not to cause a significant difference. As a result, the retainer (3) is pushed straight into the retainer accommodating chamber (17) while being substantially maintained in a free state without being extremely deformed. Therefore, the tightening force for tightening the tightening cylinder (2) can be efficiently converted to the pressing force for pressing the insertion end of the bellows tube (8) via the retainer (3), and the retainer (3 )
Since the front surface of the divided member (37) is formed of a flat surface, in the state shown in FIG. 6 in which the tightening cylinder (2) is tightened to the final position, the divided member is The front surface of (37) has an O groove in the annular groove (19) facing it.
Press the ring (14) in the retaining state and at the same time make the annular groove (19)
Is pressed uniformly on the open edge.

Thus, the gap between the bite portion (33) continuing to the front surface of the dividing member (37) and the open edge of the annular groove (19) corresponding to the outer edge of the pipe receiving surface (15) is formed. The foremost ridge (81) of the bellows tube (8), which is located at the bottom, is pressed against the open edge of the annular groove (19) by the front face of the biting portion (33) and is crushed, and the outer end is formed. A part of the ridge (81) projecting outward from the edge is pushed into the annular groove (19), and the dividing member
The front portion of (37) is pressed in a pressed state together with the O-ring (14).

In this case, the tube receiving surface (15) and the annular groove (19)
The bellows tube (8) is fixed by crushing the bellows tube (8) at the boundary edge of the bellows, so that the sealing performance of the bellows tube (8) is improved as compared with the configuration in which the bellows tube (8) is pressed between the surfaces, In this state, the front end of the retainer (3) is
The inner peripheral wall of the bellows prevents the bellows (8) from being inadvertently pulled. It does not fall out of (82) and the bellows tube (8) does not fall out.

Incidentally, when the depth of the retainer housing chamber (17) is set so that the cylindrical member (40) is simultaneously pushed together with the dividing member (37), the cylindrical member (40) is as described above. Then, since the pressing end surface (25) of the tightening cylinder (2) is pushed from the rear and protrudes outward, the cylindrical member (40) together with the dividing member (37) is inserted into the retainer accommodating chamber (17). By being forcibly pushed, the retainer chamber (1
7) It is possible to further secure the retention.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a partially cutaway portion of a flexible pipe joint according to an embodiment of the present invention.

FIG. 2 is a partially cutaway sectional view showing a state in which a bellows tube is inserted into the flexible pipe joint according to the embodiment of the present invention.

FIG. 3 is a sectional view of a retainer of the flexible pipe joint according to the embodiment of the present invention.

FIG. 4 is a side view of a tubular member to be externally fitted to a retainer of the flexible pipe joint according to the embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a state in which a tubular member is externally fitted to a retainer of the flexible pipe joint according to the embodiment of the present invention.

FIG. 6 is a partially cutaway cross-sectional view showing a state in which tightening of the tightening cylinder in the flexible pipe joint according to the embodiment of the present invention has been completed.

FIG. 7 is an explanatory view showing a state in which a bellows tube is inserted into a conventional flexible pipe joint before tightening (lower half view), and an explanatory view after completion of tightening (upper half view).

FIG. 8 is an explanatory view showing an actual state of connection of a bellows pipe of a conventional flexible pipe joint.

[Explanation of symbols]

 (1) ・ ・ ・ Coupling main body (17) ・ ・ ・ Retainer storage chamber (2) ・ ・ ・ Tightening cylinder (3) ・ ・ ・ Retainer (31) ・ ・ ・ Thin wall (32) ・ ・ ・ Slit (33 ) ・ ・ ・ Bite-in part (37) ・ ・ ・ Divided member (8) ・ ・ ・ Collapsible tube (81) ・ ・ ・ Crest (82) ・ ・ ・ Valley

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Higashitaro Higashiguchi 18 Fujimi Alloy Co., Ltd., 1-18 Hana Toba, Minami-ku, Kyoto (56) References JP-A-8-159350 (JP, A) JP-A-9-189390 (JP, A) JP-A-4-125389 (JP, A) JP-A-9-189391 (JP, A) JP-A-2000-161562 (JP, A) Utility model registration 2510623 (JP, Y2) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16L 33/00-33/34

Claims (2)

(57) [Claims] 1. A tubular joint main body, a tightening cylinder screwed into the joint main body from behind, and externally fitted to a bellows tube located in front of the tightening cylinder and inserted from the rear. An annular retainer pushed into a retainer housing chamber in the joint main body, wherein the retainer is a plurality of metal segments having a plurality of arc-shaped cross-sections that are positioned side by side in the circumferential direction through slits cut from a front end. The divided members are connected to each other at a thin portion at a rear end, and the front end of the retainer is elastically expandable and contractable with the thin portion as a fulcrum. Inside the front end of each split member, in a flexible pipe joint in which a bite portion that bites into the valley portion of the bellows tube is formed, an inner diameter of the bite portion of the retainer in a free state is:
The outer diameter of the peak of the bellows tube is set smaller than the outer diameter of the valley, and the retainer storage chamber is formed in a cylindrical shape, and the inner diameter of the cylinder keeps the retainer substantially in the free state. The front end portion is set to a size that allows the front end portion to be externally fitted in an expansion preventing state. An annular concave portion is formed on the outer periphery of each of the divided members, and the annular concave portion is separate from the divided member. A cylindrical member made of an elastic synthetic resin or rubber having a plurality of grooves formed from a front end toward a rear side is housed in an externally fitted state, and a rear end of the cylindrical member has the same material as the cylindrical member. A flange portion formed integrally with the outer periphery of the joint body, and an annular engagement convex portion with which the flange portion abuts from the rear is projected from an inner peripheral wall of the joint main body, and a front end surface of the tightening cylinder. Has two concentric annular end faces, The outer annular end surface on the side is a pressing end surface located at a position advanced forward from the inner annular end surface on the inner peripheral side, and the rear end surface of the tubular member is displaced outward and forward from the rear end of the retainer. When the tightening tube is tightened, the pressing end surface of the tightening tube abuts on the pressure receiving end surface of the cylindrical member, and the inner annular end surface of the tightening tube is formed of the retainer. At the back end,
A flexible pipe joint characterized by being set to be opposed to each other with a small gap therebetween. 2. The flexible pipe joint according to claim 1, wherein
A tube receiving surface with which the insertion end of the bellows tube abuts is provided forward of the retainer storage chamber, and O is provided outside the tube receiving surface.
Forming an annular groove into which a ring is loaded, and when the retainer is pushed to the final position in the retainer storage chamber, the front portion of the retainer prevents the O-ring in the annular groove from being pulled out; A flexible pipe joint which is set so that a front portion of the continuous biting portion presses an outer peripheral area of an insertion end portion of the bellows tube against an outer edge of the tube receiving surface.