JP3295653B2 - Flexible pipe joint - Google Patents

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 joint for connecting a flexible metal bellows pipe to a connected portion, for example, when connecting a gas pipe to a gas cock. Applicable to

[0002]

2. Description of the Related Art A joint having the structure shown in FIG. 9 has already been proposed as a joint for connecting a flexible metal bellows tube to a portion to be connected (Japanese Patent Application No. 10-271613). In this case, a connected cylinder connected to the gas inlet of the gas cock, etc.
A tightening cylinder (2) is screwed into one end of (1), and a retainer (3) that contracts in diameter by tightening the tightening cylinder (2) fits over the bellows pipe (91). This is kept in a retaining state.

For this reason, the tightening cylinder (2) in the retainer (3)
A flange (38) is provided on the outer periphery of the side end, and the flange (38) is fixed to the projecting portion (11) that is annularly continuous along the inner periphery of the connected cylinder (1). The bellows tube (91) is engaged from the side of the attachment tube (2), whereby the front end of the retainer (3) is opposed to the tube receiving surface (51) of the connected tube (1).
Is projected one mountain. Also, the above flange
By forming a notch (39) around the inner peripheral portion of (38), a thin portion (381) that is easily broken is formed. Also, retainer
(3) has a slit (31) cut in the axial direction from the tip
(31) are formed at a constant pitch in the circumferential direction. Further, a tapered portion (17) into which the retainer (3) is pushed is formed in the connected cylinder (1).

In this device, when a bellows pipe (91) is inserted from the rear end of the tightening cylinder (2), the first ridge (92) at the front end of the bellows (91) engages with the engaging projection (37) at the front end of the retainer (3). Abuts on the retainer (3)
Move in the insertion direction while pushing out the tip of. As a result, the engaging projections (3) are located in the valleys (93) following the first ridges (92).
7) is engaged with the outside, and the bellows tube (91) projects from the tip of the retainer (3) by one mountain. In this state, tighten the cylinder (2)
The flange (38) of the retainer (3) is broken at the thin portion (381) by the tightening force of the tightening cylinder (2), and the retainer (3) from which the flange (38) has been removed moves forward. Then, it is pushed into the tapered portion (17). Then, the retainer (3) contracts in diameter and the engaging projection (37) digs deeply into the valley (93) of the bellows tube (91), and the first peak (92) of the bellows tube (91) rises. Tip of retainer (3) and pipe receiving surface of connected cylinder (1) facing it
The compression is flattened in (51). Thereby, the bellows pipe (91) is connected to the connected cylinder (1).

In this device, the flange (38) on the outer periphery of the retainer (3) is engaged with the projection (11) on the inner periphery of the connected cylinder (1), so that the retainer (3) and the connected cylinder are connected. The interval between the pipe receiving surfaces (51) of (1) can be set to an appropriate interval (an interval in which only one tip of the bellows tube (91) protrudes from the retainer (3)).

[0006]

However, in the above-mentioned prior art, when the tightening cylinder (2) is tightened, the flange (38) of the retainer (3) breaks at the thin portion (381), and this breaks. A bellows tube (91) that has been connected because it remains in the joint
There is a problem that it is difficult to pull out and reconnect.

That is, when the tightening cylinder (2) is removed from the connected cylinder (1) in order to reconnect the bellows pipe (91) that has been excessively connected, the annular flange () separated from the retainer (3) is removed. 38) bellow tube
It is directly caught in the valley (93) on the outer periphery of (91). Therefore, in this state, after the bellows tube (91) is pulled out from the connected tube (1) together with the retainer (3), if the bellows tube (91) is further pulled out from the tightening tube (2) or the like, the bellows tube (91) is pulled out. The flange (38) hooked on the valley (93) of the) interferes with the bellows tube (91)
Cannot be smoothly pulled out from the tightening cylinder (2), and the work of reconnecting the bellows pipe (91) is difficult.

The present invention has been made in view of such a point, and "protrudes into the connected tube (1) from within the tightening tube (2) screwed into one end of the connected tube (1). A retainer (3) surrounding the outer periphery of the distal end of the bellows pipe (91), wherein the retainer (3) is screwed into the tightening cylinder (2),
From the temporary fixing position in the connected cylinder (1), it is forcibly pushed into the retainer accommodating chamber and contracts in diameter, and the valley of the bellows pipe (91) is reduced.
(93) to the flexible pipe fitting which fits outside in the unfolded state.
It is an object of the present invention to ensure that a member for holding the retainer (3) at the temporary fixing position does not separate from a portion where the retainer (3) is disposed, so that the operation of reconnecting the bellows pipe (91) can be performed smoothly. * 1

[0009]

Means for Solving the Problems The technical means of the present invention taken to solve the above-mentioned problem is that "a retainer (3) has a concave formed on the outer periphery near the front end in the pushing direction of the retainer (3)". An elastic ring (55) externally fitted in the groove (36), a projection provided on the inner periphery of the connected cylinder (1), and screwing of the fastening cylinder (2) into the projection. The retainer (3) is provided on the outer periphery of the retainer (3) so as to
(2) is provided with a flange having a strength that is deformed so that the engagement is released by a pushing force acting on the retainer (3), and the flange of the fastening cylinder (2) is screwed into an outer peripheral edge of the flange. A bent piece (35) projecting rearward in the direction is provided in a manner continuous in the circumferential direction, and the retainer (3) is fastened by the fastening cylinder (2) screwed into the connected cylinder (1). ) Is pressed, a flange relief space recessed toward the joint center axis side from the tip of the protruding portion is formed in a portion that continues to the flange in the screwing direction of the tightening cylinder (2). Is done. "

When the connecting operation of the bellows pipe (91) is performed using the flexible pipe joint of the present invention, the tightening cylinder is connected in the same manner as the above-mentioned conventional one.
When the bellows tube (91) is inserted from the rear end of (2), the diameter of the retainer (3) is forcibly expanded by the peak of the bellows tube (91), and then the diameter is contracted by the urging force of the elastic ring (55).
As a result, the tip of the bellows tube (91) projects from the retainer (3). At this time, the flange on the outer periphery of the retainer (3) is engaged with the projection provided on the inner periphery of the connected cylinder (1) from behind in the screwing direction of the tightening cylinder (2). Accordingly, the retainer (3) is held at the temporary fixing position with respect to the connected cylinder (1).

Next, when the tightening cylinder (2) is screwed into the connected cylinder (1) and tightened, the tightening force at this time causes the connected cylinder (1) to be tightened.
The flange on the outer periphery of the retainer (3) engaged with the protrusion of the third member is deformed. That is, when the tightening cylinder (2) is tightened, the retainer
The retainer (3) moves while the outer peripheral flange of (3) remains engaged with the protruding portion of the connected cylinder (1).
The flange is deformed rearward in the tightening direction of the tightening cylinder (2).
At this time, the flange is tightened with respect to the flange.
Deforms so as to escape into the flange relief space formed in the part that continues to the back in the screwing direction of (2) (the connection cylinder (1) is recessed toward the center axis of the joint from the tip of the protrusion on the inner periphery). I do. That is, unlike the above-mentioned conventional one, the flange does not separate from the retainer (3). As a result, the engaged state between the connected cylinder (1) and the retainer (3) is released, and the retainer (3) moves in the screwing direction together with the flange, and the retainer housing chamber on the inner periphery of the connected cylinder (1). Pushed into. As a result, the retainer (3) moves the bellows tube (9
The bellows tube (91) is fitted to the valley portion (93) of (1), and the bellows tube (91) is in a retaining state.

Next, the operation of pulling out the bellows tube (91) that has been connected in excess will be described. Loosen the tightening cylinder (2) and connect it to the connected cylinder.
(1), then remove the bellows tube (91) from the connected tube (1).
Forcibly withdrawn from Then, the retainer (3) in the contracted diameter state moves together with the bellows tube (91) in the pulling-out direction with the retainer (3) still fitted on the tip of the bellows tube (91). In this case, the flange provided on the outer periphery of the retainer (3)
Since it has not been separated from the retainer (3) at the time of the above-mentioned bellows connection operation, it moves together with the retainer (3) in the pull-out direction of the bellows shaft (91).

Therefore, in this case, the flange, which is a member for holding the retainer (3) in the temporary fixing position, is provided with a tightening cylinder.
It only deforms with the tightening of (2) and this is the retainer (3)
When the fastening tube (2) is removed from the connected tube (1), the flange does not catch on the bellows tube (91) as in the conventional case described above, so that the bellows tube (91) is not separated. From the tightening cylinder (2) smoothly.

[0014]

According to the present invention having the above configuration, the following specific effects are obtained. A flange for holding the retainer (3) in the temporary fixing position will retain the retainer even if the tightening cylinder (2) is tightened.
Since it is not separated from the bellows tube (91), the work of reconnecting the bellows tube (91) can be performed more smoothly than the above-mentioned conventional one in which the flange is separated from the retainer (3) when the bellows tube (91) is connected. Since the bent piece (35) that is continuous in the circumferential direction is provided on the outer peripheral edge of the flange, the deformation strength of the thin flange can be increased even when the flange is thin. Therefore, retainer before assembly
Even if an unexpected external force acts on the flange during the handling of (3), the flange is unlikely to be deformed. [Others] * 2. In the flexible pipe joint according to the above item 1, "the flange portion of the retainer (3) is fitted into the connected cylinder (1) in a state in which it cannot move in the radial direction." Stuff, retainer
(3) is positioned in the radial direction within the connected cylinder (1), thereby preventing the retainer (3) from rattling in the radial direction. * 3. Contrary to the above-mentioned item 1, the above problem can be solved even if the flange is provided on the connected cylinder (1) side.

That is, "the connecting cylinder (2) is engaged with the projection provided on the outer periphery of the retainer (3) so as to engage with the projection from the front in the screwing direction of the tightening cylinder (2). A flange provided on the inner periphery of 1) and deforming so that the engagement is released by a pushing force acting on the retainer (3) from the tightening cylinder (2); In a state where the retainer (3) is pushed by the tightening tube (2) screwed into the tube (1), a portion that is continuous with respect to the flange in the front of the tightening tube (2) in the screwing direction. In addition, a flange clearance space is formed which is larger in the direction away from the joint center axis than the tip of the protruding part, '' when the retainer (3) is moved by the tightening force of the tightening cylinder (2). The flange on the inner periphery of the connected cylinder (1) engaged with the projection on the outer periphery of the retainer (3) is deformed. That is, a flange clearance space formed at a portion that is continuous with the flange in the screwing direction of the tightening cylinder (2) in a direction away from the center axis of the joint than the tip of the protruding portion on the outer periphery of the retainer (3). ) So that the flange escapes into the inside. Therefore, even in this case, the flange does not separate from the connected cylinder (1) when the bellows is connected.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described together with the illustrated example. As shown in FIG. 1, the flexible pipe joint according to the present embodiment includes a connected cylinder (1) connected to a gas cock, and a retainer (3) inserted into the connected cylinder (1).
And a tightening cylinder (2) for pushing the retainer (3) into the back of the connected cylinder (1), and these connected cylinders (1),
The fastening cylinder (2) and the retainer (3) are made of a metal material such as brass.

The details of each section will be described below. [Regarding Connected Tube (1)] As shown in FIGS. 1 and 2, a gas inlet (not shown) of a gas cock (not shown) is provided on the outer periphery of the downstream end (the upper end in FIG. 1) of the connected tube (1). A male screw (10) is screwed into the hole.

The connected cylinder (1) has a female screw (13) engraved on the inner periphery of the screwing side end of a tightening cylinder (2), which will be described later, on the upstream side. A projection (11) is formed on the inner periphery on the downstream side of (13) (in front of the tightening cylinder (2) in the screwing direction), and the projection (11) is formed on the inner surface of the connected cylinder (1). It is continuous over the entire circumferential direction. On the inner circumference of the connected cylinder (1), an annular ridge (119) adjacent to the upstream side of the protrusion (11) (rearward in the screwing direction of the tightening cylinder (2)) is provided in the entire circumferential direction. The inner diameter of the annular ridge (119) portion is formed so as to be connected to the projection (11).
It is set slightly larger than the inner diameter of the part.

A retainer escape portion (15) having an enlarged inner diameter of the connected cylinder (1) is formed downstream of the formation portion of the protruding portion (11). The retainer escape portion (15) is formed to secure a space that allows the outer periphery of the tip of the retainer (3) to spread when the bellows tube (91) is forcibly inserted into the retainer (3) described later. is there. A tapered portion (17) is formed on the inner periphery of the downstream end side of the retainer escape portion (15), which is a retainer storage chamber whose diameter decreases gradually toward the front in the screwing direction of the tightening cylinder (2). A small-diameter gas passage (18) is continuous downstream of the tapered portion (17). A tubular portion (19) extends at the upstream end of the gas passage (18), and the tubular portion (19)
An annular groove (5) for mounting an O-ring (52) is provided on an annular pipe receiving surface (51) connected from the base end of the tapered portion (17) to the small-diameter end of the tapered portion (17).
3) is formed. [Regarding Tightening Tube (2)] The tightening tube (2) screwed into one end of the connected tube (1) has a wrench engaging portion (22) having a hexagonal outer periphery and a It has a cylindrical portion (23) that follows.
Also, a male screw (29) is provided on the outer periphery of the cylindrical portion (23) in the middle of the axial direction.
And a small-diameter cylindrical portion (205) to be inserted into a retainer (3) described later protrudes from the distal end of the cylindrical portion (23). A retainer pressing surface (28) extending from the base end of the small-diameter tube portion (205) to the outside in the radial direction of the tightening tube (2) comes into contact with the end surface of the retainer (3).

The outer diameter of a portion (239) of the cylindrical portion (23) that continues from the retainer pressing surface (28) to the upstream side is an annular ridge (119) in the connected cylinder (1). It is smaller by a predetermined dimension than the inner diameter of the part. This allows the flange
A flange relief space (S) recessed toward the joint center axis from the end of the protruding portion (11) is provided in a portion that continues to the rear in the screwing direction of the tightening cylinder (2) with respect to (38). Is formed.

The inner periphery of the wrench engaging portion (22) is covered with a covering tube (95) made of an elastic synthetic resin for covering the outer periphery of the bellows tube (91).
A concave portion (24) for loading a waterproof packing (27) in contact with (see FIG. 3) is provided. [Retainer (3)] The retainer (3) pushed deep into the connected cylinder (1) by screwing the tightening cylinder (2) into
The main body (30) formed in a cylindrical shape as a whole and the tightening cylinder
The retainer (3) has a slit (31) (31) cut in the axial direction from the downstream end face, in addition to a thin flange (38) projecting from the outer periphery of the end on the (2) side. ) Are arranged in a circumferential direction at a pitch of 90 degrees. And slit (31)
The bottom wall portions (34) and (34) of (31) are formed to be thin, so that the inner diameter of the downstream end portion of the retainer (3) can be easily enlarged.
It is easy to bend so that it can contract. Also, retainer
As described above, the flange (38) is provided around the outer periphery of the end of the tightening cylinder (2) in (3), and the flange (3)
The outer diameter of 8) is the same as that of the connected cylinder (1).
Substantially coincides with the inner diameter of the portion. Therefore, retainer (3)
With the flange (3) attached to the connected cylinder (1).
The outer peripheral surface of (8) comes into substantially contact with the inner peripheral surface of the annular ridge (119), whereby the retainer (3) does not rattle in the connected cylinder (1) in the radial direction, and the outer peripheral surface of the annular protrusion (119) does not rattle. Connection tube (1)
And is positioned coaxially. A gap (103) is provided between the outer periphery of the retainer (3) near the base end of the flange (38) and the inner periphery of the protruding portion (11) in the connected cylinder (1). Is formed.

The outer peripheral edge of the flange (38) is provided with a tightening cylinder (2).
A bent piece (35) as a three-dimensional body projecting toward the side is provided in a manner continuous in the circumferential direction. The bending piece (35) is provided because the strength of the thin-walled flange (38) is increased to increase the strength of the flange.
This is to prevent (38) from waving in the circumferential direction.
Therefore, even if an unexpected external force acts on the flange (38) during handling of the retainer (3) before assembling the joint, the flange (38) is less likely to be deformed.

A concave groove (36) in which an elastic ring (55) is fitted is formed on the outer periphery near the distal end of the retainer (3), and the inner peripheral surface of the downstream distal end of the retainer (3) is formed. Is provided with an engaging projection (37). In the natural state where the tip of the retainer (3) does not expand or contract, the engagement protrusion (3
The diameter of the circle connecting the inner peripheral end of 7) is set slightly smaller than the diameter of the peak of the bellows tube (91) and larger than the diameter of the valley of the bellows tube (91).

The elastic ring 55 may be a C-ring having elasticity or an elastic rubber ring. [Assembly work of flexible pipe joint] In order to assemble the flexible pipe joint according to the present embodiment using the above-mentioned parts, first, the connected pipe (1) starts from the upstream end of the connected pipe (1). Retainer inside
Insert (3). In this case, the retainer (3) is positioned such that the flange (38) formed at one end of the retainer (3) faces rearward.
Into the connected cylinder (1). Then, the flange (38) of the retainer (3) is moved from the upstream side (from the rear in the screwing direction of the tightening tube (2)) to the protruding portion (11) of the inner periphery of the connected tube (1).
Engage. In this state, the outer peripheral surface of the flange (38) is substantially in contact with the inner peripheral surface of the annular protruding portion (119) provided around the connected cylinder (1).
(3) is positioned coaxially with the connected tube (1) and the tightening tube (2). That is, the retainer (3) is prevented from rattling in the radial direction in the connected cylinder (1).

Next, a tightening cylinder is attached to the female screw (13) of the connection cylinder (1).
Screw in the male screw (29) of (2), thereby tightening the tightening cylinder.
The retainer pressing surface (28) at the front end of (2) is once loosely contacted with the base end surface (360) of the retainer (3) opposed thereto, and then is slightly unscrewed and retracted. Thereby, the tightening cylinder (2) is attached to the initial position. As a result, the engaging projection (37) at the tip of the retainer (3) and the pipe receiving surface (5
Distance L ₁ between 1) is set to a dimension of about a mountain portion of the bellows tube below (91). [Regarding connection work of bellows pipe (91)] Next, the work of connecting the bellows pipe (91) as a flexible pipe to a connection object such as a gas cock using the above-mentioned flexible pipe joint will be described.

As shown in FIG. 3, the male screw (10) at the downstream end of the connected cylinder (1) and the gas inlet of the gas cock (G) are screwed in advance. Next, as shown in the same figure, when a flexible bellows pipe (91) for gas supply is inserted from the rear end which is the upstream end of the tightening cylinder (2), the bellows pipe (91) at the top of the bellows pipe (91) is inserted. The first ridge (92) comes into contact with the engaging projection (37) of the retainer (3). From this state,
When the bellows tube (91) is forcibly pushed, the engagement projection (37) is strongly pushed outward in the radial direction by the first peak (92). Then, the tip of the retainer (3), which is easily deformed in the radial direction due to the formation of the slits (31), (31), is attached to the elastic ring.
The diameter is increased against the urging force of (55), whereby the engaging projection (37) of the retainer (3) climbs over the first peak (92) of the bellows tube (91) and continues to the valley. It matches the part (93). At this time, the distal end of the retainer (3) contracts in diameter due to the urging force of the elastic ring (55), whereby the engaging projection (37) is reduced to the valley portion of the bellows tube (91).
(93) loosely engaged. Then, the flange (38) of the retainer (3) engaging with the projecting portion (11) on the inner circumference of the connected cylinder (1) causes the engaging convex portion (37) of the retainer (3) to be connected to the connected convex portion (37). cylinder (1) bellows tube as the distance L ₁ is already described tube receiving surface (51)
Since it is set to one mountain of (91), the first of the bellows pipe (91)
Only the peak (92) protrudes downstream from the retainer (3) (see FIG. 4).

When the tightening cylinder (2) is tightened from the state shown in FIG. 4, when the retainer pressing surface (28) of the tightening cylinder (2) is used, the retainer (3)
Is pressed. When the tightening cylinder (2) is further tightened, the retainer (3) is tapered while the thin flange (38) provided at one end of the retainer (3) remains engaged with the protrusion (11). Move to (17) side. At this time, the flange (38) on the outer periphery of the retainer (3) is located between the outer periphery near the tip of the cylindrical portion (23) of the tightening tube (2) and the annular ridge (119) of the connected tube (1). Deforms so as to escape into the flange escape space (S). This forcibly releases the engagement between the retainer (3) and the projection (11) on the inner periphery of the connected cylinder (1). As described above, in the flexible pipe joint according to the present embodiment, the flange (38) does not break and separate from the main body (30) as in the related art.
Then, when the tightening cylinder (2) is further tightened, the retainer (3) pressed by the retainer pressing surface (28) of the tightening cylinder (2) moves the connected cylinder.
(1) is pushed into the tapered portion (17), which is the retainer storage chamber, and the engaging projection (37) at the tip of the retainer (3) is pushed into the bellows tube (91).
(See FIG. 5). That is, the retainer (3) is fitted to the valley (93) of the bellows pipe (91) in a state of preventing the spread. Fig. 5 shows the tightening cylinder (2) tightened to the final position.
In the condition (1), the first ridge (92) of the bellows pipe (91) is pressed and flattened by the engaging projection (37) at the tip of the retainer (3) and the pipe receiving surface (51) of the connected cylinder (1). And pressed against the O-ring (52),
The piping work is completed by ensuring the sealing performance of the tip of the bellows pipe (91).

Next, when pulling out the bellows tube (91) that has been excessively connected, the tightening tube (2) is loosened to separate it from the tube (1) to be connected, and then the bellows tube (91) is covered. Forcibly pull it out of the connection tube (1). Then, the retainer (3) in the contracted diameter state is kept fitted to the tip of the bellows tube (91) and the bellows tube (9) is kept fitted.
Together with 1), it moves in the drawing direction and escapes from the connected cylinder (1). In this case, the flange (38) provided around the retainer (3) is not separated from the retainer (3) during the bellows connection operation described above. Therefore, as compared with the case where the flange (38) is separated from the main part (30) of the retainer (3) as described above, the work of reconnecting the pulled-out bellows tube (91) to the connected tube (1) is performed more frequently. It becomes easier.

In the above embodiment, the tapered portion (17) formed in the connected cylinder (1) is used as the retainer housing chamber. However, the cylindrical empty chamber having an inner diameter uniform in the axial direction is defined as the retainer housing chamber. And the distal end of the retainer (3) is formed in a tapered shape tapering toward the distal end, and the retainer (3) contracts in diameter when the tapered portion is forcibly pushed into the cylindrical empty space. It may be. [Others] In the above embodiment, the flange (38) is provided around the end of the retainer (3). However, as shown in the imaginary line of FIG. 1 and FIG. 6, the axis of the retainer (3) extends from the end of the retainer (3). Four flanges (38) (38) arranged in the circumferential direction may be formed at positions shifted in the direction. In this case, each flange (38) (38) is
The slits (31) and (31) formed in (3) are separated from each other. Further, the cylindrical main part (30) of the retainer (3) is formed at the bottom (the end on the side of the tightening cylinder (2)) of the slits (31) and (31) formed therein. 33).
Even in this case, when the retainer (3) is pushed by the tightening cylinder (2), the retainer (3) is formed at a portion that is continuous with the flange (38) behind the screwing direction of the tightening cylinder (2). The flanges (38) and (38) are deformed so as to escape into the flange escape space (S). FIG. 7 shows a configuration in which an annular protruding portion (11) protruding along the inner circumference of the connected cylinder (1) is fitted to the cylindrical main body (30) of the retainer (3). In this outer fitting, retainer
(3) is positioned coaxially with the connected cylinder (1). Even with this, when the tightening cylinder (2) is tightened, a flange relief space formed in a portion that is continuous with the flange (38) behind the screwing direction of the tightening cylinder (2) is formed.
The flange (38) is deformed so as to escape to (S). In the above embodiment, the flange (38) is provided around the outer periphery of the retainer (3). Conversely, as shown in FIG. 8, a thin-walled engagement portion is provided on the inner periphery of the connected cylinder (1). Around the flange (100) and tighten the cylinder (2) against the flange (100).
Insert the protruding part (300) that comes into contact
(3) may be provided around the periphery. Then, the flange (1
00) is configured to abut along the outer peripheral surface (301) of the retainer (3), and the inner periphery of the connected cylinder (1) and the protrusion of the retainer (3) at the base end of the flange (100). A gap outer peripheral surface (305) is formed between the outer peripheries of the portion (300),
Set the dimensions of each part. In addition, a flange relief extending in a direction away from the center axis of the joint with respect to the flange (100) in a portion continuing forward in the screwing direction of the tightening cylinder (2) with respect to the flange (100). A space (S) is formed.

In this case, the flange (100) is connected to the connected cylinder.
(1) side, the point where the projection (300) engaging with the flange (100) is provided on the retainer (3) side, and the flange relief space (S) is Downstream side (Tightening cylinder (2)
(The front in the screw-in direction) is configured in the same manner as in the above embodiment. In this case, the tightening cylinder (2)
When the retainer (3) moves in the tightening direction with the tightening, the flange engaged with the protrusion (300) of the retainer (3)
(100) is deformed so as to escape into the retainer escape space (2). As a result, the engagement between the flange (100) and the projection (300) of the retainer (3) is released, and the retainer (3) is pushed into the tapered portion (17) of the connected cylinder (1). Therefore,
Even in this case, the flange (100) does not separate from the connected cylinder (1). Therefore, the work of reconnecting the bellows tube (91) that has been connected excessively can be performed smoothly.

In FIG. 8, the flange (10
0) downstream from the tip (forward in the screwing direction of the tightening cylinder (2))
By providing a three-dimensional body (integrally formed with the flange (100)) projecting around the entire circumference,
It is desirable to improve the strength of 0). This is to prevent the retainer (3) inserted into the connected cylinder (1) from being easily deformed when the tip of the retainer (3) hits the flange (100).

[Brief description of the drawings]

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

FIG. 2 is a sectional view of a flexible pipe joint according to the first embodiment of the present invention.

FIG. 3 is an operation explanatory view of the flexible pipe joint according to the first embodiment of the present invention, showing a state immediately before the bellows pipe (91) is inserted into the retainer (3).

FIG. 4 is an operation explanatory view of the flexible pipe joint according to the first embodiment of the present invention, showing a state in which a bellows pipe (91) is inserted through a retainer (3).

FIG. 5 is an operation explanatory view of the flexible pipe joint according to the first embodiment of the present invention, showing a state in which the tightening of the tightening cylinder (2) is completed.

FIG. 6 is a sectional view of an embodiment in which a flange (38) is provided forward from a rear end of a retainer (3).

[Fig. 7] (11) Projecting portion (11) of connected cylinder (1) is retainer (3).
Sectional view of a main part of a flexible pipe joint having a structure abutting on a cylindrical main body (30) of FIG.

FIG. 8 is a cross-sectional view of a flexible pipe joint according to another embodiment.

FIG. 9 is an explanatory diagram of the prior art.

[Explanation of symbols]

(1) ・ ・ ・ Connected cylinder (11) ・ ・ ・ Circular upright wall (17) ・ ・ ・ Tapered part (18) ・ ・ ・ Gas passage (2) ・ ・ ・ Tightening cylinder (22) ・ ・ ・ Spanner Engagement part (3) ・ ・ ・ Retainer (100) ・ ・ ・
Flange (91) ・ ・ ・ bellow tube

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Higashitaro Higashiro 18 Kaname Toba Hanana, Minami-ku, Kyoto 1 Inside Fujii Alloy Manufacturing Co., Ltd. (72) Inventor Yasuji Shimizu 18 Kaname Toba, Minami-ku, Kyoto No. 1 in Fujii Alloy Manufacturing Co., Ltd. (56) References JP-A-2000-130671 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16L 33/00 F16L 33/28

Claims (3)

(57) [Claims] 1. A tightening cylinder screwed into one end of a connected cylinder (1).
(2) A retainer (3) surrounding the outer periphery of the bellows pipe (91) projecting into the connected cylinder (1) from the inside, wherein the retainer (3) is screwed. The tightening tube (2) is forcibly pushed into the retainer storage chamber from the temporary fixing position in the connected tube (1) and contracts in diameter to reduce the diameter of the bellows tube (9).
In the flexible pipe joint which is fitted to the valley portion (93) of (1) in an expansion preventing state, a concave groove () formed on the outer periphery near the front end in the pushing direction of the retainer (3). An elastic ring (55) externally fitted to the connecting cylinder (36), a projection provided on the inner periphery of the connected cylinder (1), and a screwing direction of the tightening cylinder (2) into the projection. Strength that is provided on the outer periphery of the retainer (3) so as to engage from the rear and is deformed so that the engagement is released by a pushing force acting on the retainer (3) from the tightening cylinder (2). A bent piece (35) protruding rearward in the screwing direction of the tightening cylinder (2) is provided on an outer peripheral edge of the flange in a manner continuous in the circumferential direction, In a state where the retainer (3) is pushed by the fastening cylinder (2) screwed into the connected cylinder (1), the retainer (3) is connected to the flange in the rearward direction of the fastening cylinder (2) in the screwing direction. In a portion, flexible pipe joint flange relief space recessed joint center axis side is formed from the tip of the protrusion. 2. The flexible pipe joint according to claim 1, wherein the flange portion of the retainer (3) can be fitted into the connected cylinder (1) in a state in which it cannot move in a radial direction. Flexible pipe joint. 3. A tightening cylinder screwed into one end of the connected cylinder (1).
(2) A retainer (3) surrounding the outer periphery of the bellows pipe (91) projecting into the connected cylinder (1) from the inside, wherein the retainer (3) is screwed. The tightening tube (2) is forcibly pushed into the retainer storage chamber from the temporary fixing position in the connected tube (1) and contracts in diameter to reduce the diameter of the bellows tube (9).
In a flexible pipe fitting which is fitted to the valley (93) of (1) in a state of preventing expansion, a protrusion provided on the outer periphery of a retainer (3), and the tightening cylinder ( 2) is provided on the inner circumference of the connected cylinder (1) so as to engage from the front in the screwing direction of 2), and the engaging force is applied from the tightening cylinder (2) to the retainer (3). A flange having a strength capable of deforming so that the connection is released, and in a state where the retainer (3) is pushed by the tightening cylinder (2) screwed into the connected cylinder (1), the flange is attached to the flange. On the other hand, a flexible pipe joint in which a flange relief space is formed in a portion continuing forward in the screwing direction of the tightening cylinder (2) in a direction away from the center axis of the joint than the tip of the protrusion.