JP3762380B2 - Flexible pipe joint - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flexible pipe joint, and more particularly to a joint for connecting a flexible bellows pipe.
[0002]
[Prior art]
As a joint for connecting a flexible bellows tube to a connected portion such as a gas inlet of a gas cock, for example, a joint disclosed in Japanese Patent Laid-Open No. 2002-250488 of Patent Document 1 or Japanese Patent Laid-Open No. 2001-2001 of Patent Document 2 There are those disclosed in Japanese Patent No. 21085.
As shown in FIG. 6, the former is a cylindrical joint body (4) having a gas passage (40) connected to a gas pipe including a joint, and a rear side of the joint body (4) (in the drawing, A fastening cylinder (41) which is screwed in from the right side), an annular retainer (42) which is positioned in front of the fastening cylinder (41) and can be expanded and contracted in the radial direction; and the joint body The packing member (43) is accommodated in an annular groove (47) formed deeper than the retainer (42) in (4).
[0003]
A taper inner peripheral surface (44) that expands toward the front end is formed on the inner periphery of the front end portion of the tightening cylinder (41), and the retainer that faces the taper inner peripheral surface (44). A tapered outer peripheral surface (46) is formed at the rear of (42). Further, a pressing portion (45) for pressing the peak portion of the bellows tube (5) forward is projected from the front end portion of the retainer (42).
[0004]
When the bellows tube (5) is inserted from the rear side of the fastening tube (41) into the joint in which the various parts are assembled, the pressing portion of the retainer (42) at the peak portion of the bellows tube (5) The bellows tube (5) passes through the retainer (42) while expanding and contracting the retainer (42) while pushing (44) from the rear. The front end portion of the bellows tube (5) that has passed through the retainer (42) has the packing member (43) elastically placed in an annular groove (47) formed outside the gas passage (40). It is inserted while being pressed to be connected to the outer peripheral airtight state.
[0005]
Thus, in the conventional joint, when the bellows pipe (5) is inserted into the joint, it is connected in an airtight state, and when a pulling direction force is applied to the bellows pipe (5), the retainer ( Since the outer peripheral surface (46) of 42) comes into contact with the inner peripheral surface (44) of the tightening tube (41), the pressing portion (45) further bites into the valley portion. (5) will be connected to the retaining state. Thus, in the conventional one shown in FIG. 6, the connection work of the bellows tube (5) is facilitated without complicating the structure of the joint.
[0006]
However, in the conventional joint described above, the bellows pipe (5) is held in a state where it is prevented from coming off due to the contact between the taper outer peripheral surface (46) and the taper inner peripheral surface (44). Are connected while maintaining the height of the bellows wave formed in the initial state, and when pulled by a strong pulling force, the peak portion is pushed by the pressing portion and deformed in the reduced diameter direction. As a result, the bellows tube (5) may be forcibly pulled out or a connection failure may occur.
[0007]
In the latter flexible pipe joint, as shown in FIG. 7, the packing member (43) is densely filled in the annular groove (47) provided outside the gas passage (40), and the tightening tube (41 ) To the final tightening position, press the peak (52) at the tip of the bellows tube (5) against the open edge of the annular groove (47) with the pressing part (45) of the retainer (42). By squeezing, the bellows tube (5) is connected in a retaining state. In this case, a strong tightening force is required to tighten the tightening tube (41) to the final tightening state while crushing the crest (52) at the tip of the bellows tube (5). ) Is applied with a relatively strong pulling force, the crushing state of the peak portion (52) is maintained, and the bellows tube (5) is not pulled out.
[0008]
Thus, the connection of the bellows tube (5) is easy, but the former joint, which may be pulled out when pulled with a strong force, is effective for pipe connection under the floor or inside the wall, etc. The connection of the bellows tube (5) requires a tool, but the latter joint in which the once connected bellows tube (5) is not pulled out is effective for pipe connection outdoors.
[0009]
However, since these conventional joints can be connected only by one of the connection methods, the connection method of the joints cannot be changed at the work site in accordance with the piping installation conditions.
In addition, since the bellows tube (5) cannot be removed from both joints, after the bellows tube (5) is connected, the bellows tube (5) must be reconnected for reasons such as detection of foreign matter contamination or poor airtightness. If you want, you must cut the bellows tube (5) and connect a new joint. In this type of joint, when the tightening tube (41) is pulled out from the joint body (4), the various members constituting the joint are disassembled into pieces, and assembly adjustment is required again. Since it is not easy at the work site, as described above, the bellows tube (5) is cut, the joint is discarded, and a new joint is used, which is uneconomical.
[0010]
[Patent Document 1]
JP 2002-250488 A
[Patent Document 2]
JP 2001-21085 A
[0011]
[Problems to be solved by the invention]
The present invention is a "tubular joint body in which a gas passage is formed;
A tightening cylinder screwed into the joint body from behind;
A flexible comprising an annular retainer provided at the front end of the clamping tube and fitted on a valley portion of a bellows tube inserted into the clamping tube and having a pressing portion that presses the front peak portion. It is possible to provide a flexible pipe joint that allows the bellows pipe to be connected by different connection methods depending on the installation location of the joint, and allows easy re-connection and reuse of the joint even after connection. Let it be an issue.
[0012]
[Means for Solving the Problems]
* 1
The technical means of the present invention for solving the above-mentioned problem is as follows: “An annular recess that opens toward the front end surface of the pressing portion of the retainer is provided on the outer side in the radial direction of the gas passage in the joint body. Formed concentrically with the passage,
In the annular recess, a cylindrical seal member is loaded along the outer peripheral wall thereof,
In the annular space formed between the cylindrical seal member and the inner peripheral wall of the annular recess, a metal cylinder configured to be shorter in the axial direction than the seal member can be removably inserted,
In a state where the tightening tube is tightened, a tip of the bellows tube faces the annular space portion, and in a state where the tightening tube is completely tightened, a mountain portion in front of the pressing portion holds the seal member. It is set to be connected to the outer airtight state by elastically pressing,
Retaining means capable of fixing the tightening cylinder in the tightening completed state to the joint body in a retaining state is provided,
The retaining means is set to be releasable by a tool ”.
The technical means operates as follows.
When a cylindrical seal member is loaded into the annular recess in the joint body, an annular space portion is formed between the cylindrical seal member and the inner peripheral wall of the annular recess. In addition, the bellows tube is inserted into the tightening tube before being screwed into the joint body from behind, and set so that the peak portion of the bellows tube protrudes forward from the pressing portion of the retainer at the front end of the tightening tube. To do. As described above, when the fastening tube is screwed into the joint body in a state where the pressing portion is externally fitted to the valley portion of the bellows tube, the screw of the bellows tube is engaged with the fastening tube. The peak portion protruding forward from the pressing portion of the retainer is pressed by the pressing portion, and the bellows tube is inserted into the joint body together with the fastening cylinder.
[0013]
When the metal cylinder is not inserted into the space portion, the peak portion protruding forward from the retainer of the bellows tube is inserted into the space portion while elastically pressing the inner surface of the seal member. . When the tightening tube is tightened to the final tightening position, the tightening tube is fixed to the joint main body by the retaining means. This state is the connection completion state of the bellows tube, and the front portion of the bellows tube from the retainer is connected to the outer peripheral airtight state and the retaining state by the cylindrical seal member.
[0014]
When the metal tube is inserted into the annular space portion, when the tightening tube is tightened, the tip of the bellows tube comes into contact with the rear end surface of the metal tube, and when the tightening tube is completely tightened, A peak portion in front of the pressing portion is squeezed between the rear end surface of the metal tube and the front end surface of the pressing portion, and is crushed into an outer airtight state. In this state, the tightening cylinder can be fixed to the joint main body in a retaining state by retaining means. This is the connection completion state of the bellows tube. In this state, since the seal member is housed in a manner that protrudes rearward than the metal cylinder, the tightening cylinder is tightened until the front end surface of the pressing portion substantially contacts the rear end surface of the metal cylinder. The rear end portion of the seal member is elastically pressed by the pressing portion. Further, since the crest portion in the crushed state also elastically presses the inner peripheral surface portion of the seal member, the bellows tube is connected in a state where airtightness is ensured.
[0015]
In either case, since the retaining means is set so that it can be released using a tool, after the release, the screwing of the fastening cylinder is loosened and the fastening cylinder is moved to the joint body. When retracted, the bellows tube can be pulled out from the joint body together with the fastening cylinder. The joint body after the bellows tube is pulled out together with the tightening tube is the same as the state before the bellows tube is inserted, and in the connection with the metal tube inserted, the crest of the tip in the crushed state is obtained. If the part is cut and the bellows tube is reset to the fastening cylinder in the initial state, it can be inserted into the joint body together with the fastening cylinder and connected.
[0016]
* Section 2
In item 1, “the retaining means includes an elastic ring that can be reduced in diameter in the radial direction and a predetermined position on the outer peripheral surface of the body portion of the fastening cylinder along the circumferential direction, and elastically deforms the elastic ring. An outer groove having a depth capable of accommodating the entire body in a closed state, and an outer peripheral portion of the elastic ring formed in a predetermined position on the inner peripheral surface of the body portion of the joint body along the circumferential direction and elastically restored. It consists of an inner groove with a depth to fit,
When the tightening of the tightening cylinder is completed, the outer groove is set so as to correspond to the inner groove ''. By elastically deforming the elastic ring in the diameter-reducing direction, the elastic ring is attached to the tightening cylinder. When the tightening cylinder is screwed into the joint body in this state, the tightening cylinder is screwed into the joint body. When the final tightening position of the tightening cylinder is reached and the outer groove corresponds to the inner groove in the joint body, the elastic ring is elastically restored in the diameter increasing direction, and the outer peripheral portion of the elastic ring is the inner groove. Abuts on the bottom. At this time, a snapping sound is made and further screwing of the fastening cylinder is prevented. Thereby, it can be recognized by sound and touch that the tightening cylinder has reached the final tightening position. With the elastic ring fitted in the inner groove, the tightening cylinder is connected to the joint body in a state that prevents it from coming off, so the tightening cylinder cannot be loosened by hand force alone. If the tightening cylinder is rotated in the direction of loosening, the elastic ring is reduced in diameter by being pushed by the front open end of the outer groove as the tightening cylinder moves rearward. Pushed out of the inner groove into the outer groove. This is a state in which the retaining means of the retaining means is released. If the fastening cylinder is pulled out in this state, the fastening cylinder can be pulled out from the joint body together with the bellows tube.
[0017]
* Section 3
2. In the joint body, “the joint body is formed with a plurality of through-holes penetrating the body portion in the radial direction and communicating with the inner groove. Is filled with a breathable waterproof member ”, the breathable waterproof member filled in the through-hole does not allow liquids such as rainwater to pass from the outside into the joint body, but gas from the joint body to the outside. Can be passed. Therefore, when a gas leak occurs due to a hole in the bellows tube by nailing or the like during piping work, the gas leaked into the joint body will permeate the breathable waterproof member and flow out to the outside. From this, it is possible to detect gas leakage after pipe connection. Thus, the through hole can function as a gas escape passage for gas leak detection. Further, when it is desired to redo the connection work of the bellows tube due to a connection failure or the like, the breathable waterproof member is removed from the through hole, and a pin-like insertion tool is simultaneously inserted into the plurality of through holes. Since the through-hole is configured to communicate with an inner groove that accommodates the elastic ring for retaining, the insertion of the tool into the through-hole causes the elastic ring to be pressed inward to be contracted. It can be elastically deformed in the radial direction. The elastic ring having a reduced diameter can be pushed into the outer groove of the tightening tube, and the bellows tube can be removed from the joint body together with the tightening tube by loosening the tightening of the tightening tube in this state. .
[0018]
* Item 4
In each of the above items, “a tool-corresponding portion having a diameter larger than that of the body portion protrudes in the radial direction at the rear end portion of the tightening tube, and when the tightening of the tightening tube is completed, the tool-corresponding portion The front surface is set so as to be pressed against the rear end surface of the joint body via the annular packing ”, the annular packing is attached to the front surface of the tool corresponding part or the rear end surface of the joint body. In this configuration, when the tightening cylinder is tightened until it reaches the final tightening state, the tightening cylinder can be attached to the joint body in an airtight outer peripheral state via the annular packing.
[0019]
【The invention's effect】
Since the present invention has the above configuration, the present invention has the following specific effects.
In the case where the joint is installed under the floor or inside a wall where there is little chance that force in the pulling direction acts on the bellows tube accidentally or intentionally, the bellows tube is not inserted into the annular recess. What is necessary is just to insert in an annular space part and to make it connect in the retaining state. In this case, since connection is easy, work efficiency is good.
[0020]
In addition, when the joint is installed outdoors where there is a relatively high opportunity to apply a pulling-direction force to the bellows tube due to force majeure or mischief, the metal tube is inserted into the annular recess, and the rear end surface of the metal tube The crest portion at the tip of the bellows tube is crushed and connected with the pressing portion of the retainer. Since this state is held by the retaining means, even if a strong pulling force acts on the bellows tube, it is possible to reliably prevent the bellows tube from falling off the joint.
[0021]
As described above, since two types of connection methods of the bellows tube are possible with one joint, an operator selects which connection method is used to connect the bellows tube at the work site according to the installation location of the joint. This increases the range of use of the joint.
[0022]
In addition, if it is desired to reconnect the bellows tube after the bellows tube has been connected due to problems such as foreign matter contamination or airtightness, the bellows tube can be connected to the joint body together with the fastening cylinder by releasing the retaining means with a tool. In addition, the joint body and the fastening cylinder can be reused as they are. Even in the case of a connection method with a metal tube inserted, if only the crushed part at the tip of the bellows tube is cut, the bellows tube can be easily reconnected at the work site and reused any number of times. Possible easy-to-use joints can be provided.
[0023]
In the second item, in addition to the above-described effect, whether or not the bellows tube is securely connected and the tightening cylinder is tightened to the final tightening position is recognized by the sound and feel accompanying the elastic return of the elastic ring. Therefore, the operator can easily confirm the completion of the connection of the bellows tube. Further, the structure and structure of the retaining means are simple.
[0024]
Further, in the item of item 3, there is an effect that the gas escape passage can be used as a tool insertion hole for elastically deforming the elastic ring.
In the item of item 4, there is an effect that a more reliable sealing property can be expected in the connection state of the bellows tube.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Next, the embodiment of the present invention described above will be described in detail with reference to the drawings.
A flexible pipe joint according to an embodiment of the present invention includes a joint body (1) connected to a gas inlet (51) of a gas stopper, and a tightening tube (2) screwed to the joint body (1). And a retainer (3) provided at the front end of the tightening tube (2) and elastically expandable / contractible in the radial direction. FIG. 1 shows a tightening tube (1) in the joint of the first embodiment. 2) shows a state before tightening, and FIG. 2 shows a final tightening state in which the tightening tube (2) is tightened from the state of FIG. 1 to the final tightening position.
[0026]
Hereinafter, details of each part in the joint of the first embodiment will be described.
[Fitting body (1)]
On the outer periphery of the front end portion (left end in the drawing), which is the downstream end side of the joint body (1), a male screw portion (10) for being screwed into the gas inlet portion (51) of the gas stopper is engraved. A gas passage (18) is formed on the inner peripheral side. An annular recess (11) having a predetermined depth and opening rearward is formed concentrically with the gas passage (18) on the radially outer side of the rear open end of the gas passage (18). In the annular recess (11), a cylindrical seal member (12) for ensuring airtightness of the bellows tube (5) described later is loaded so as to be in close contact with the outer peripheral wall (11a) of the annular recess (11). In the annular space portion (17) formed between the inner peripheral surface of the seal member (12) and the inner peripheral wall (11b) of the annular recess (11), an annular metal tube (15 ) Is densely loaded.
[0027]
In this embodiment, when the metal cylinder (15) and the seal member (12) are loaded in a state where they are pushed in until they reach the bottom surface of the annular recess (11), the seal member (12) is the metal cylinder ( The mutual dimensions are set so as to protrude rearward from 15).
[0028]
Further, the width of the annular space portion (17) is set so as to substantially match the thickness of the metal tube (15), and it is formed from the crest and trough of the bellows tube (5). The height of the bellows wave is approximately the same.
[0029]
A female thread part (13) for screwing the tightening cylinder (2) is engraved on the inner peripheral surface of a certain range of the central part excluding the front end side and the rear end side of the joint body (1). An inner groove (14) is formed behind the female screw portion (13) so as to open inward.
[0030]
[Clamping tube (2)]
The fastening cylinder (2) is composed of a small-diameter cylinder part (21) screwed into the joint body (1) and a tool corresponding part (22) which is continuous to the rear and has a hexagonal outer periphery. It is configured. The tool-corresponding portion (22) has a flat diameter larger than the outer diameter of the rear end portion of the joint body (1), and a single annular groove (20a) opens forward at the front end portion. Is formed. A part of the annular packing (20) is fitted into the annular groove (20a).
[0031]
Further, a concave portion (23a) is provided on the inner peripheral surface of the tool corresponding portion (22), and the concave portion (23a) is a coated tube made of an elastic material that covers the outer periphery of the bellows tube (5). A waterproof packing (23) having a substantially T-shaped cross section that is in airtight and watertight contact with (50) is loaded. Even when the flexible pipe joint according to the present embodiment is used in the outdoor piping section by the waterproof packing (23), the rainwater adhered to the surface of the cladding pipe (50) from the rear end portion of the tightening cylinder (2). Is prevented from entering the joint.
[0032]
A male screw part (24) that can be screwed into the female screw part (13) is formed on the outer peripheral surface of the small-diameter cylindrical part (21), and is located behind the formation area of the male screw part (24). The outer peripheral surface of the joint body (2) is a position corresponding to the inner groove (14) provided in the joint body (1) when the fastening body (1) is fastened to the joint body (1) until the final fastening position is reached. In addition, an outer groove (25) is formed. A C-shaped elastic ring (26) is engaged with the outer groove (25).
[0033]
The depth and width of the outer groove (25) are set so as to substantially match the diameter of the cross section of the C-shaped elastic ring (26), and the C-shaped elastic ring (26) is in a free state. In some cases, the dimensions are set such that the outer groove (25) can be accommodated in the outer groove (25) in a state of protruding outward from the outer groove (25) and being elastically deformed in the reduced diameter direction.
[0034]
[Retainer (3)]
The retainer (3), which is pushed into the joint body (1) by screwing the tightening cylinder (2) into the joint body (1), has its rear half (3b) at the front end of the tightening cylinder (2). A front half portion (3a) that is externally connected to the engagement tube portion (27) and pushes the peak portion (52) at the tip of the bellows tube (5) forward than the inner diameter of the rear half portion (3b). Is an elastic cylinder made of metal having a smaller inner diameter, and can be expanded and contracted in the radial direction by forming one slit (not shown) in the axial direction.
[0035]
The inner peripheral surface of the front half (3a) of the retainer (3) is a tapered inner peripheral surface (30) that is reduced in diameter toward the front, and the front end that is the smallest diameter portion is a bellows tube (5 ) Functions as a pressing part (33) that pushes forward.
In the natural state where the distal end of the retainer (3) does not expand or contract, the inner diameter of the distal end of the pressing portion (33) is configured to be small enough to fit deeply into the valley of the bellows tube (5), and the retainer (3) The overall outer diameter is set to substantially match the inner diameter of the joint body (1).
[0036]
As a result, in the state where the tightening cylinder (2) is tightened and the retainer (3) is accommodated in the joint body (1), the retainer (3) is held in the state of being prevented from expanding, and the retainer ( The front end surface of the pressing portion (33) of 3) is in a mode of facing substantially the entire area of the open end of the annular space portion (17).
[0037]
[Assembly of flexible pipe joint]
In order to assemble the flexible pipe joint according to the first embodiment of the present invention using each of the above parts, first, the rear end (3b) of the retainer (3) is attached to the front end of the tightening cylinder (2). The retainer (3) is rotatably integrated with the fastening cylinder (2).
[0038]
Then, the bellows tube (5) is inserted into the tightening tube (2) from the rear of the tightening tube (2).
When the bellows tube (5) is inserted, the foremost crest (52) presses the tapered inner peripheral surface (30) of the retainer (3), and accordingly, the front half (3a) of the retainer (3). Expands in the radial direction. Thereby, the peak portion can pass through the pressing portion (33) while pushing the tapered inner peripheral surface (30) outward.
[0039]
In this embodiment, as shown in FIG. 1, the state where only the most distal peak (52) of the bellows tube (5) protrudes forward from the front end of the retainer (3) is a bellows tube ( 5) Assemble to the tightening cylinder (2).
The pressing portion (33) is configured in such a manner that the front end portion of the pressing portion (33) protrudes greatly inward so as to be deeply fitted into the valley portion following the peak portion (52). If the width of the slit is set to be relatively large, the tip portion of the retainer (3) can be expanded with a small pushing force to pass through the peak portion (52).
[0040]
As described above, the fastening tube (2) in which the retainer (3) and the bellows tube (5) are assembled together is screwed from the rear of the joint body (1). At this time, the elastic ring (26) is elastically deformed in the diameter-reducing direction and inserted into the joint body (1) while being accommodated in the outer groove (25), whereby the tightening cylinder (2) is Then, it can be smoothly inserted into the joint body (1), and then the male screw portion (24) is screwed into the female screw portion (13).
[0041]
As the tightening tube (2) is tightened, it advances to the front of the joint body (1), and accordingly, the pressing portion (33) of the retainer (3) passes through the peak portion (52) of the bellows tube (5). By pushing forward, the front end of the peak (52) can be brought into contact with the rear end surface of the metal tube (15). From this state, the tightening cylinder (2) is further tightened. Since the retainer (3) is housed in a substantially contact state in the formation region of the female thread portion (13) of the joint body (1), the diameter expansion is prevented, and the peak portion (52) is securely connected to the metal cylinder. The rear end face of (15) can be pressed.
[0042]
Further, by tightening with a tool, the peak portion (52) is clamped between the rear end surface of the metal tube (15) and the front end surface of the pressing portion (33) and tightened until reaching the final tightening position. In the completed state, as shown in FIG. 2, the crest (52) at the front end of the bellows tube (5) is crushed between the rear end surface of the metal tube (15) and the front end surface of the pressing portion (33). It becomes the mode made.
[0043]
Since the relationship between the height of the seal member (12) and the metal tube (15) is as described above, the front end surface of the pressing portion (33) moves the peak portion (52) behind the metal tube (15). When the end surface is pressed and crushed, the front end surface of the pressing portion (33) is configured to press the seal member (12). Further, since the relationship between the height of the bellows wave of the bellows tube (5), the thickness of the metal tube (15) and the width of the annular space portion (17) in which it is accommodated, is as described above. When the crest (52) is crushed, the top of the crest (52) also presses the seal member (12). Thus, the bellows tube (5) is connected to the outer peripheral airtight state by pressing the seal member (12) against the top of the peak portion (52) and the front end surface of the pressing portion (33). It becomes.
[0044]
At this time, as shown in FIG. 3, the outer groove (25) of the tightening cylinder (2) is just opposite to the inner groove (14) of the joint body (1), so that it is in the outer groove (25). The elastic ring (26) accommodated in the elastically deformed state is elastically returned to the bottom of the inner groove (14) with a strong force in the diameter increasing direction. At this time, the elastic ring (26) hits the bottom of the inner groove (14) and makes a clicking sound, and at the same time, further tightening is prevented. Thereby, it can be recognized with sound and touch that the tightening cylinder (2) has been tightened until it reaches the final tightening position. This is the connection completion state of the bellows tube (5).
[0045]
In this assembled state, when a force in the pulling direction is applied to the bellows tube (5), the retainer (3) is held in the diameter expansion preventing state as described above, and the fastening cylinder (2) Since the elastic ring (26) is engaged and fixed to the joint body (1) so as not to come off, the peak portion (52) at the tip of the bellows tube (5) is connected to the pressing portion (33). The state of being crushed by the front end portion of) is maintained, and this state does not change unless the engagement of the elastic ring (26) is released and the tightening degree of the tightening cylinder (2) is loosened. Therefore, for example, in the case of outdoor piping, even if force in the pulling direction acts on the bellows tube (5), pulling of the bellows tube (5) from the tightening tube (2) is reliably prevented. It becomes.
[0046]
In addition, if the tightening cylinder (2) is not tightened to the final tightened state and the crushing degree of the crest (52) at the tip of the bellows tube (5) is insufficient, the outer groove (25) Since it does not correspond to the inner groove (14) and the elastic ring (26) cannot obtain the sound and feel of elastic return, it can be recognized that the tightening of the tightening cylinder (2) is insufficient.
As shown in FIG. 3, the inner groove (14) is set to a dimension equal to or smaller than the radius of the elastic ring (26).
[0047]
The elastic ring (26) once fitted in the inner groove (14) is strongly pressed against the bottom of the inner groove (14) by its elastic force. Although it cannot be rotated in the loosening direction, the elastic ring (26) can be removed by associating the tool with the tool corresponding part (22) and rotating the clamping cylinder (2) with the tool in the loosening direction. Pushed rearward by the front open end of the groove (25) to contact the rear open end of the outer groove (25), forcibly elastically deformed in the diameter reducing direction, escaped from the inner groove (14), and outer groove (25). If the elastic ring (26) can be accommodated in the outer groove (25), the fastening cylinder (2) can be removed from the joint body (1) by rotating it in the direction of loosening the screw.
[0048]
Thus, the fastening cylinder (2) after being connected to the joint body (1) can be easily taken out from the joint body (1) by using a tool. As the tightening tube (2) is pulled out rearward, the bellows tube (5) can be easily pulled out.
[0049]
Therefore, after the connection of the bellows tube (5) is completed, if it is detected that foreign matter is mixed in the joint body (1) or that the airtightness is poor, the tightening tube (2) is By loosening at (1), the fastening tube (2) can be removed from the joint body (1) together with the bellows tube (5). Since the joint body (1), the fastening cylinder (2), and the retainer (3) after being removed are the same as before the connection, the peak portion (52 ), And then again by setting the bellows tube (5) in the fastening tube (2) in the manner described above, the joint body (1) can be connected.
[0050]
Furthermore, in this embodiment, in order to further facilitate the removal of the tightening cylinder (2) using a tool, the through hole (19) penetrating the body portion of the joint body (1) is provided as described above. It is formed so as to communicate with the inner groove (14). The two through holes (19) are preferably formed at positions facing each other along the diameter of the joint body (1), and the pair of through holes (19) are simultaneously formed as shown in FIG. By inserting the tip of the insertion tool (31) and pressing the elastic ring (26) inward, the elastic ring (26) can be forcibly elastically deformed in the reduced diameter direction. Thus, the tightening cylinder (2) can be pulled out of the joint body (1) by rotating the tightening cylinder (2) in a loosening direction while reducing the diameter of the elastic ring (26). In this case, it is not necessary to use a tool for rotating the fastening cylinder (2), and it can be loosened by hand.
The through hole (19) is filled with a breathable waterproof member (17) when not used as a tool insertion hole.
[0051]
The breathable waterproof member (17) is a member that allows gas such as gas to pass through but does not allow liquid such as rainwater to pass through.By filling the through hole (19) with the breathable waterproof member (17), It is possible to prevent rainwater and the like from entering the joint. Also, if a gas leak occurs from the bellows tube (5) if a hole is opened in the bellows tube (5) by nailing during operation, the bellows tube (5) and the cladding tube (50) The gas that has entered the joint body (1) from the outside leaks out of the joint body (1) through the breathable waterproof member (17). Thus, the through hole (19) can also function as a gas escape passage. This gas leak can be detected by a pressure drop during pipe inspection.
[0052]
In the connection completion state of the bellows tube (5), as described above, the top portion of the peak portion (52) of the bellows tube (5) and the front end surface of the pressing portion (33) are in pressure contact with the seal member (12). Thus, the bellows tube (5) is connected to the outer peripheral airtight state, and the waterproof packing (23) provided on the tool corresponding portion (22) of the fastening tube (2) is covered with the bellows tube (5). The outer surface of the pipe (50) is brought into an airtight state.
[0053]
Further, in the final tightened state, the rear end portion of the joint body (1) and the front end portion of the tool corresponding portion (22) are set so as to be in close contact with each other, but the tool corresponding portion (22) As described above, the annular groove (20a) is formed on the front end surface of the front end surface so as to open forward, and the groove (20a) is loaded with the annular packing (20). Airtightness is maintained between the rear end portion of the main body (1) and the front end portion of the tool corresponding portion (22) by the annular packing (20).
[0054]
Next, the joint according to the second embodiment will be described.
FIG. 4 shows a state before tightening of the tightening tube (2) of the second embodiment, and FIG. 5 shows the state from the state of FIG. 4 to the tightening tube (2) to the final tightening position. The final tightened state is shown.
The joint body (1), tightening tube (2) and retainer (3) structure of the second embodiment can be the same as those employed for the joint of the first embodiment described above. In this embodiment, only the seal member (12) is loaded in the annular recess (11) of the joint body (1), and the inner peripheral surface of the seal member (12) and the annular recess (11 The annular space portion (17) is still formed between the inner peripheral wall (11b) of the).
[0055]
The width of the annular space portion (17) is the height of the bellows wave formed by the peak and valley portions of the bellows tube (5), as in the case of the first embodiment. The depth of the annular recess (11) is set to such a depth that two ridges of the bellows tube (5) can be inserted. In the embodiment, the state in which the two peak portions of the bellows tube (5) protrude forward from the front end of the retainer (3) is the assembly completion state of the bellows tube (5).
[0056]
The tightening tube (2) can be tightened by hand.With the tightening, the tightening tube (2) advances forward of the joint body (1) and protrudes forward of the retainer (3). Two peaks of the tube (5) are pushed into the space (17). Since the relationship between the height of the bellows wave of the bellows tube (5) and the width of the space portion (17) is as described above, the bellows tube (5) is a crest of the seal member (12). The inner peripheral surface is pressed into the space portion (15) while being pressed. At this time, since the retainer (3) is housed in a substantially contact state in the formation region of the female thread portion (13) of the joint body (1), the diameter expansion is prevented, and the peak portion of the bellows tube (5) Can be reliably pushed in the direction of pushing into the space portion (15).
[0057]
As shown in FIG. 2, in the connection completion state where the tightening cylinder (2) is tightened until it reaches the final tightening position, the two crests at the front end of the bellows tube (5) are sealed members (12). As shown in FIG. 3, as in the case of the first embodiment, the outer groove (25) of the tightening tube (2) and the joint body are pressed against the inner peripheral surface of the tube in an airtight state. The fastening cylinder (14) and the retaining means comprising the elastic ring (26) that elastically recovers in the direction of diameter expansion toward the bottom of the inner groove (14) act as a tightening cylinder ( In 2), it will be held in a state where it is tightened until it reaches the final tightening position.
[0058]
In this assembled state, when a force in the pulling direction is applied to the bellows tube (5), the retainer (3) is held in the diameter-expanded state as described above, so 2 from the front of the bellows tube (5). The rear surface of the claw peak portion comes into contact with the pressing portion (33), and the withdrawal of the bellows tube (5) from the tightening tube (2) is prevented.
[0059]
In the second embodiment, the tightening cylinder (2) can be tightened by hand tightening, so that the elastic return of the elastic ring (26) can be recognized by hand feeling. In addition, if the front end of the bellows tube (5) is not inserted into the annular space portion (15), for example, if the bellows tube (5) is inserted distorted, the pressing portion of the retainer (3) Since unnecessary addition is applied to (33), it is possible to recognize the connection failure of the fastening cylinder (2) with the touch of the hand.
[0060]
If the tightening cylinder (2) is not tightened in the final tightened state and the insertion length of the front end portion of the bellows tube (5) into the space (15) is insufficient, the outer groove (25 ) Does not correspond to the inner groove (14) and the elastic ring (26) cannot be elastically restored and feel the same, and in this case too, the tightening cylinder (2) is not sufficiently tightened. You can also recognize that.
The structure in which the elastic ring (26) is elastically deformed in the diameter reducing direction to release the retaining means and the airtight structure in the joint body are the same as those in the first embodiment.
[0061]
In the joint of the second embodiment, the connection of the bellows tube (5) is simple, but if the force in the pulling direction is so strong that the bellows tube (5) is deformed, it is pulled out. Since there is a possibility, it can be effectively used as a joint for pipe connection in a place where a drawing force does not act, such as under the floor or inside a wall.
[0062]
In this way, by providing the metal cylinder (15) so as to be detachable with respect to one joint, the bellows tube can be attached in two ways as shown in the first and second embodiments. Since the connection can be made, the worker can select the connection method of the bellows tube at the work site according to the conditions such as the installation location of the pipe.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state before a fastening tube of a flexible pipe joint according to a first embodiment of the present invention is screwed into a joint body.
2 is an enlarged cross-sectional view of a main part showing a state in which a fastening tube of a flexible pipe joint is tightened to a final fastening position from the state of FIG. 1;
FIG. 3 is an enlarged cross-sectional view of a main part in a state where a tightening cylinder is tightened to a final tightening position.
FIG. 4 is a cross-sectional view showing a state before a fastening tube of a flexible pipe joint according to a second embodiment of the present invention is screwed into a joint body.
FIG. 5 is an enlarged cross-sectional view of a main part showing a state where the fastening tube of the flexible pipe joint is tightened to the final tightening position from the state of FIG. 4;
FIG. 6 is a cross-sectional view showing an example of a conventional flexible pipe joint.
FIG. 7 is a cross-sectional view showing another example of a conventional flexible pipe joint.
[Explanation of symbols]
(1) ・ ・ ・ ・ Fitting body
(11) ... Annular recess
(11a) ・ ・ ・ ・ Outer peripheral wall
(11b) ... Inner peripheral wall
(12) ... Cylindrical seal member
(15) ... Metal cylinder
(17) ... Annular space
(18) ... Gas passage
(2) ... Tightening cylinder
(3) ... Retainer
(33) ... Pressing part
(4) ... Bellows tube
(5) ... Bellows tube
(52) ... ・ Yamabe

Claims (4)

A tubular joint body in which a gas passage is formed;
A tightening cylinder screwed into the joint body from behind;
A flexible comprising an annular retainer provided at the front end of the clamping tube and fitted on a valley portion of a bellows tube inserted into the clamping tube and having a pressing portion that presses the front peak portion. In pipe fittings,
An annular recess that opens toward the front end surface of the pressing portion of the retainer is formed concentrically with the gas passage on the radially outer side of the gas passage in the joint body.
In the annular recess, a cylindrical seal member is loaded along the outer peripheral wall thereof,
In the annular space formed between the cylindrical seal member and the inner peripheral wall of the annular recess, a metal cylinder configured to be shorter in the axial direction than the seal member can be removably inserted,
In a state where the tightening tube is tightened, a tip of the bellows tube faces the annular space portion, and in a state where the tightening tube is completely tightened, a mountain portion in front of the pressing portion holds the seal member. It is set to be connected to the outer airtight state by elastically pressing,
Retaining means capable of fixing the tightening cylinder in the tightening completed state to the joint body in a retaining state is provided,
The flexible pipe joint, wherein the retaining means is set so as to be releasable by a tool. The flexible pipe joint according to claim 1, wherein the retaining means is
An elastic ring that can be reduced in diameter in the radial direction, and a depth that is formed along a circumferential direction at a predetermined position on the outer peripheral surface of the body portion of the fastening cylinder and that can accommodate the whole in a state where the elastic ring is elastically deformed And an inner groove formed along a circumferential direction at a predetermined position on the inner peripheral surface of the body portion of the joint body and having a depth in which the outer peripheral portion of the elastic ring in a state of being elastically restored is shallowly fitted. ,
The flexible pipe joint according to claim 1, wherein when the tightening of the tightening cylinder is completed, the outer groove is set to correspond to the inner groove. 3. The flexible pipe joint according to claim 2, wherein the joint body is formed with a plurality of through-holes penetrating the body portion in the radial direction and communicating with the inner groove, and is used during normal use. In the flexible pipe joint, the through hole is filled with a breathable waterproofing member. The flexible pipe joint according to any one of claims 1 to 3, wherein a tool-corresponding portion having a diameter larger than that of the body portion projects in a radial direction at a rear end portion of the fastening tube, and the fastening tube The flexible pipe joint is set so that the front surface of the tool corresponding portion is pressed against the rear end face of the joint body via the annular packing when the tightening is completed.

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