JP2012047233A - Pipe joint, and hot water supply device, air conditioning device and floor heating device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint which can improve connection workability to a pipe and a place to be connected without incurring twist of the pipe and damage of an elastic seal member causing leakage of a fluid.SOLUTION: The pipe joint 10 includes: an inner cylinder 14; an outer cylinder 15 disposed outside in a radial direction of the inner cylinder 14 and forming a space S which can insert the pipe P between the outer cylinder 15 and the inner cylinder 14; a screw cylinder 16 provided on the base end of the outer cylinder 15 to be integrally rotatable in a sate relatively rotatable to the inner cylinder 14 and also having a screw part screwed to the place to be connected U1; an elastic seal member 36 provided on the inner cylinder 14 and adhering to the peripheral surface of the pipe P inserted into the space S; and a holding mechanism 47 provided on the outer cylinder 15 and holding the pipe P while permitting the relative rotation between the pipe P inserted into the space S and the outer cylinder 15.

Description

  The present invention relates to a pipe joint, and a hot water supply device, an air conditioner, and a floor heating device using the same.

  In recent years, a heat pump type hot water supply apparatus has become widespread as a clean hot water supply system in consideration of the global environment. The heat pump type hot water supply apparatus includes a heat pump unit that incorporates a refrigerant circuit that generates hot water by a refrigeration cycle, and a water storage unit that stores the hot water generated by the heat pump unit. In addition, in the heat pump hot water supply system, on-site installation work, communication piping for circulating hot water between the heat pump unit and the water storage unit, and communication for supplying hot water from the water storage unit to hot water use equipment such as a bathtub. Pipes are routed and connected to each unit and hot water equipment.

  In general, a pipe joint is used to connect a communication pipe to each unit or hot water utilization equipment. For example, as shown in FIG. 21, the conventional pipe joint is disposed on the radially outer side of the inner cylindrical body 114 and the inner cylindrical body 114, and a connecting pipe is inserted between the inner cylindrical body 114. An outer cylinder 115 that forms a space, a screw cylinder 116 having a male screw provided on the proximal end side of the inner cylinder 114, an elastic seal member 136 attached to the outer peripheral surface of the inner cylinder 114, And a holding ring 142 mounted on the inner peripheral surface of the outer cylinder 115. The inner cylinder 114 and the screw cylinder 116 are integrally formed, and the outer cylinder 115 is screwed to the proximal end side of the inner cylinder 114 (see, for example, Patent Document 1).

  Conventionally, a pipe joint 210 shown in FIG. 22 is also known. This pipe joint 210 is relative to the inner cylinder 214, the outer cylinder 215 integrally screwed to the outer side in the radial direction of the inner cylinder 214, and the proximal end side (the right side in the figure) of the inner cylinder 214. And a nut 216 that is rotatably connected. An elastic seal member 236 is mounted on the outer peripheral surface of the inner cylindrical body 214, and a holding ring 242 is mounted on the inner peripheral surface of the outer cylindrical body 215. The proximal end portion of the inner cylindrical body 214 is inserted into the distal end side (the left side in the figure) of the nut 216, and a retaining member 220 such as a C ring is press-fitted into a groove 219 formed on the inner peripheral surface of the nut 216. Therefore, the nut 216 is prevented from coming off.

JP 2006-138378 A

In order to connect the pipe joint 110 shown in FIG. 21 to the connection pipe and the connected portion such as the hot water supply unit, first, the screw tube 116 of the pipe joint 110 is screwed into the connected portion and then attached. In general, a connecting pipe is inserted into a space S formed between the cylindrical body 114 and the outer cylindrical body 115. However, depending on the installation environment, it may be desirable to attach the pipe joint 110 to the connection pipe first and then connect the pipe joint to the connected portion.
In such a case, since the inner cylinder body 114, the outer cylinder body 115, and the screw cylinder 116 are integrated in the pipe joint of Patent Document 1, the pipe joint 110 is connected to the connecting pipe. If the screw tube is to be screwed into the connected portion, the connecting pipe turns around with the inner cylinder 114 and the outer cylinder 115, or the elastic seal member 136 rubs against the inner peripheral surface of the connecting pipe. The sealing performance decreases, and the possibility of fluid leakage increases.

  On the other hand, in the pipe joint 210 shown in FIG. 22, the nut 216 is coupled to the inner cylinder 214 so as to be relatively rotatable. Therefore, even if the pipe joint 210 is connected to the connecting pipe first, the nut 216 is connected. Can be rotated by itself and screwed into the connected part. However, since this pipe joint 210 needs to incorporate a C-ring 220 for retaining the nut 216, the number of parts increases and the assembling work becomes complicated, resulting in an increase in manufacturing cost.

  The present invention has been made in view of the above circumstances, and enhances connection workability with respect to the pipe and the connected portion without causing kinking of the pipe which causes fluid leakage or damage to the elastic seal member. It is a main object to provide a pipe joint that can be used, a hot water supply device, an air conditioner, and a floor heating device using the same.

The pipe joint according to the first aspect of the present invention is a pipe joint in which the distal end side in the axial direction is connected to the pipe, and the proximal end side in the axial direction is connected to the connected place,
Of the inner cylinder and the outer cylinder, an outer cylinder that is disposed on the radially outer side of the inner cylinder and forms a space in which a tube can be inserted between the inner cylinder and the inner cylinder A threaded cylinder having a threaded portion which is provided so as to be integrally rotatable at the base end portion of the other tubular body in a state of being relatively rotatable with respect to the one tubular body, and which is screwed into a connected portion; An elastic seal member that is provided in one cylinder and is in close contact with a peripheral surface of a tube inserted into the space; and a tube that is provided in the one or other cylinder and is inserted into the space; and the other cylinder And a holding mechanism for holding the tube in a state in which relative rotation is allowed.

  According to this configuration, when the screw cylinder is screwed into the connected portion and attached with the pipe joint connected to the pipe, the other cylinder rotates integrally with the screw cylinder, but one cylinder is attached to the screw cylinder. Since the relative rotation is possible, the stopped state is maintained, and the tube is also stopped. For this reason, the pipe is not kinked or the elastic seal member is hardly rubbed and damaged by the peripheral surface of the pipe, and the sealing performance is not deteriorated. In addition, the screw cylinder and the other cylinder can be formed as a single part by forming them integrally with a single material. In this case, the number of parts can be reduced and the number of parts can be reduced. Assembling can be facilitated, and the manufacturing cost can be reduced.

In the above configuration, the screw cylinder is provided so as to be integrally rotatable at a base end portion of the outer cylinder in a state of being rotatable relative to the inner cylinder, and the elastic seal member is provided on an outer periphery of the inner cylinder. It is preferable to be provided on the surface.
According to this configuration, when the screw cylinder is screwed and attached to the connected portion with the pipe joint connected to the pipe, the outer cylinder rotates together with the screw cylinder, and the inner cylinder and the pipe rotate with the screw cylinder. It will maintain the stopped state without doing.

Further, the inner cylinder is inserted into the outer cylinder from the proximal end side of the screw cylinder in the axial direction, and the inner cylinder and the screw cylinder include a distal end side of the inner cylinder with respect to the screw cylinder. A position restricting portion that restricts the movement in the axial direction may be provided.
With such a configuration, the screw cylinder and the inner cylinder can be easily connected in a state where they are prevented from coming off, and the C-ring 220 for retaining as shown in FIG. The manufacturing cost can be further reduced without increasing the manufacturing cost.

The pipe joint according to the second aspect of the present invention is a pipe joint in which the distal end side in the axial direction is connected to the pipe, and the proximal end side in the axial direction is connected to the connected place,
An outer cylinder that is disposed on the outer side in the radial direction of the inner cylinder and is provided so as to be integrally rotatable with the inner cylinder, and forms a space in which a tube can be inserted between the inner cylinder and the inner cylinder And a screw cylinder having a threaded portion that is coupled to a base end portion of the inner cylindrical body and the outer cylindrical body in a relatively rotatable state and is screwed into a connected portion, and the inner cylindrical body And an elastic seal member that is provided on one of the outer cylinders and is in close contact with the peripheral surface of the pipe, and a pipe that is provided on either the inner cylinder or the outer cylinder and is inserted into the space. A holding mechanism for holding,
The inner cylinder or the inner cylinder and the outer cylinder are inserted into the screw cylinder in the axial direction from the proximal end side to the distal end side of the screw cylinder, and the inner cylinder or the outer cylinder The body and the screw cylinder are provided with a position restricting portion that restricts axial movement of the inner cylinder or the outer cylinder relative to the screw cylinder toward the distal end side.

  According to this configuration, when the screw cylinder is screwed and attached to the connected portion with the pipe joint connected to the pipe, the screw cylinder can be rotated independently while the inner cylinder body and the outer cylinder body are stopped. Therefore, the pipe is not kinked or the elastic seal member is hardly damaged by rubbing on the peripheral surface of the pipe, and the sealing performance is not deteriorated. Also, the inner cylinder, or the inner cylinder and the outer cylinder, are inserted into the screw cylinder in the axial direction from the proximal end side to the distal end side of the screw cylinder, and the inner cylinder or the outer cylinder and the screw cylinder are inserted. Is provided with a position restricting portion that restricts axial movement of the inner cylinder or the outer cylinder to the distal end side with respect to the screw cylinder, so that the inner cylinder or the inner cylinder and the outer cylinder The body and the screw cylinder can be easily connected in a state of retaining, and the C-ring 220 for retaining as shown in FIG. 14 is not required. Cost can be reduced. In addition, the inner cylinder and the outer cylinder can be integrally formed from a single material to form a single part. In this case, the number of parts can be reduced and the parts can be assembled more easily. This can be easily performed, and the manufacturing cost can be reduced.

In the pipe joint according to the first and second aspects, the holding mechanism is in contact with the peripheral surface of the pipe and the peripheral surface of the outer cylindrical body or the inner cylindrical body facing the peripheral surface thereof in the radial direction. It is preferable to have a holding ring configured so that the size can be reduced or enlarged, and an action part that reduces or enlarges the radial dimension of the holding ring so as to press the holding ring against the peripheral surface of the tube. .
According to this configuration, it is possible to reliably prevent the pipe from being detached from the space between the inner cylinder body and the outer cylinder body by pressing the holding ring against the pipe.

The retaining ring is provided with respect to the cylinder opposite to the cylinder provided with the elastic seal member, and at least a part of the holding ring is provided on the peripheral surface of the pipe at a radially opposed position of the elastic seal member. It is preferable to be pressed.
The holding ring includes a first holding portion that is pressed against the circumferential surface of the pipe at a position that is axially distant from a radially opposing position of the elastic seal member, and the first holding portion is integrated or separated. And a second holding portion that is formed and pressed against the peripheral surface of the pipe at a radially opposing position of the elastic seal member.
According to each of the above configurations, by pressing at least a part of the holding ring (second holding portion) against the circumferential surface of the tube, the circumferential surface of the tube is strongly pressed against the elastic sealing member, and the sealing surface by the elastic sealing member The pressure can be increased, and the sealing performance of the elastic seal member can be maintained over a long period of time.

Moreover, the cylinder provided with the elastic seal member may be provided with a locking portion that bites into and locks the peripheral surface of the tube pressed by the first holding portion.
With such a configuration, it is possible to more reliably prevent the pipe from being detached from the space between the inner cylinder body and the outer cylinder body.

In the holding mechanism, the action portion includes a first action surface for pressing the first holding portion against the peripheral surface of the tube, and a second action surface for pressing the second holding portion against the peripheral surface of the tube; The first and second working surfaces are inclined surfaces that are inclined so that a radial interval with the peripheral surface of the tube is narrower toward the distal end side in the axial direction, and are separated from each other via a step surface. It is preferable that it is formed.
With such a configuration, the first and second holding portions are pressed against the peripheral surface of the pipe by the first and second working surfaces made of inclined surfaces, so that the space between the inner cylinder body and the outer cylinder body is reduced. The tube can be prevented from being detached, and the sealing performance of the elastic seal member can be suitably maintained. In addition, since the first and second working surfaces are formed so as to be separated from each other via the step surface, the thickness dimension in the radial direction of the retaining ring can be made as small as possible. In other words, if the first and second working surfaces are constituted by continuous inclined surfaces, the entire working surface is enlarged in the radial direction, and the holding ring needs to be thickly formed with a thickness along the working surface. However, the retaining ring can be formed as thin as possible by forming a step surface between the first and second working surfaces and separating them.

Preferably, the elastic seal member has at least two seal portions in the axial direction, and the two seal portions have mutually different compression ratios due to close contact with the peripheral surface of the tube.
With such a configuration, for example, the compression rate of each seal portion is desired so that one of the seal portions suppresses initial fluid leakage and the other seal portion suppresses fluid leakage after long-term use. It becomes possible to set to.

In the above case, of the two seal portions, the seal portion having a smaller compression rate is the inner cylinder body or the outer cylinder body provided with the elastic seal member, the tube, and the radial direction of the seal portion. Within the dimensional tolerance range, the radial dimension is set so as to be in pressure contact with the peripheral surface of the pipe at a compression rate equal to or higher than a predetermined lower limit compression rate. It is preferable that the radial dimension is set so as to be in pressure contact with the peripheral surface of the pipe at a compression ratio equal to or less than a prescribed upper limit compression ratio.
By configuring in this way, even if the radial dimension of each component varies due to tolerances, both initial fluid leakage and fluid leakage after long-term use can be appropriately suppressed.

The above-mentioned pipe joint may be used for connection between a hard resin pipe or a metal reinforced resin pipe as a pipe and a connected portion.
Moreover, the above-mentioned pipe joint may be used for connection between a pipe through which a fluid that does not change phase at room temperature and a connected portion.

A hot water supply apparatus according to a third aspect of the present invention includes a heat source unit having a refrigerant circuit that generates hot water by a refrigeration cycle, a water storage unit that stores hot water generated in the heat source unit, and a water storage unit stored in the water storage unit. A hot water supply device comprising: a hot water supply device for discharging hot water; and a communication pipe for circulating hot water between the water storage unit and the hot water supply device between the heat source unit and the water storage unit,
At least one of the connection portions between the heat source unit and the connection pipe, the connection portion between the water storage unit and the connection pipe, and the connection portion between the hot water supply device and the connection pipe, the pipe joint described above Is used.

An air conditioner according to a fourth aspect of the present invention includes a heat source unit having a refrigerant circuit that generates cold / hot water by a refrigeration cycle, a water storage unit that stores cold / warm water generated by the heat source unit, and a water storage unit. Cold / hot water is circulated between the air conditioning unit that adjusts the temperature of indoor air using the stored cold / hot water as a heat exchange medium, between the heat source unit and the water storage unit, and between the water storage unit and the air conditioning unit. An air conditioner comprising a connecting pipe,
At least one of the connecting portions between the heat source unit and the connecting pipe, the connecting portion between the water storage unit and the connecting pipe, and the connecting portion between the air conditioning unit and the connecting pipe, the pipe described above. A joint is used.

A floor heating apparatus according to a fifth aspect of the present invention includes a heat source unit having a refrigerant circuit that generates hot water by a refrigeration cycle, a floor heating unit that adjusts the temperature of the floor surface by the hot water generated by the heat source unit, A floor heating device comprising a connecting pipe for circulating hot water between both units,
The pipe joint described above is used in a connection portion between the heat source unit and the communication pipe and / or a connection portion between the floor heating unit and the communication pipe.

It is preferable that a CO ₂ refrigerant is used in the refrigerant circuit of the heat source unit provided in the hot water supply apparatus, the air conditioner, and the floor heating apparatus as described above.

  ADVANTAGE OF THE INVENTION According to this invention, the connection workability | operativity with respect to a pipe | tube and to-be-connected part can be improved, without causing the kinking of the pipe | tube which causes the fluid leakage, and the damage of an elastic seal member.

It is a perspective view which shows the pipe joint which concerns on the 1st Embodiment of this invention. It is sectional drawing of the pipe joint shown by FIG. It is sectional drawing which expands and shows the mounting part of the elastic seal member and holding ring in a pipe joint. It is sectional drawing of an elastic sealing member. (A) is sectional drawing of a retaining ring, (b) is a front view of a retaining ring. It is sectional drawing which shows the state which attached the cap to the pipe joint. It is a graph which shows the relationship between the compression rate of an elastic seal member, and the permanent set rate after long-term use. It is a graph which shows the recommended range of the compression rate of an elastic seal member. It is a figure explaining a compression rate and a permanent distortion rate. It is a block diagram which shows a hot-water supply apparatus roughly. It is a block diagram which shows an air conditioning apparatus schematically. It is a block diagram which shows a floor heating apparatus roughly. It is sectional drawing of the pipe joint which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 4th Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 5th Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 6th Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 7th Embodiment of this invention. It is sectional drawing of the pipe joint which concerns on the 8th Embodiment of this invention. It is sectional drawing which shows other embodiment about an elastic seal member. It is sectional drawing which shows the pipe joint which concerns on a prior art. It is sectional drawing which shows the pipe joint which concerns on another prior art.

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
(Overall configuration of pipe joint 10)
FIG. 1 is a perspective view showing a pipe joint 10 according to a first embodiment of the present invention.
The pipe joint 10 according to the present embodiment is used to connect a pipe P through which a fluid such as a liquid or a gas flows and various devices U using the fluid. Connected to the end of the tube P, the base end in the axial direction is connected to the device U. Therefore, an insertion port 11 for inserting the pipe P is formed on the distal end side of the pipe joint 10 in the axial direction, and on the proximal end side in the axial direction, the end of the pipe (connected portion) U1 on the equipment U side. A nut 16 as a screw cylinder is provided to be screwed into the provided male screw.

  In addition, the pipe joint 10 of this Embodiment is mainly for connection with the apparatus P and the pipe P which handles liquids, such as water, seawater, a chemical | medical agent, and brine which do not change a phase mainly in normal temperature (for example, 5 to 35 degreeC). Is preferably used. Further, the pipe P is a hard resin pipe such as a cross-linked polyethylene pipe or a boribden pipe having good corrosion resistance and heat resistance, or a metal reinforced resin pipe such as a three-layer pipe in which the inner and outer surfaces of a metal pipe such as aluminum are coated with a resin material. Is used. However, the pipe P is not limited to a hard pipe, and a soft pipe such as a soft resin pipe can be used.

FIG. 2 is a cross-sectional view of the pipe joint 10 shown in FIG. In the pipe joint 10 shown in this figure, the tip end to which the pipe P is connected is shown on the left side in the figure, and the base end part connected to the connected portion U1 of the device U is shown on the right side in the figure. Yes.
The pipe joint 10 is mainly composed of an inner cylinder body 14, an outer cylinder body 15, and a nut 16. The inner cylinder body 14, the outer cylinder body 15, and the nut 16 are made of a metal material such as lead-free bronze or gun metal, or a hard resin material. The inner cylindrical body 14 is formed in a cylindrical shape, and an annular notch groove 17 is formed on the outer peripheral surface of the distal end portion thereof. An elastic force which will be described later is provided on the base end side (right side in FIG. 2) from the notch groove 17. An annular mounting groove (seal mounting portion) 18 for mounting the seal member 36 is formed. The inner peripheral surface of the base end portion of the inner cylindrical body 14 is formed on a tapered surface 19 whose inner diameter is increased toward the base end side.

  An annular first protrusion 21 that protrudes radially outward is formed at the proximal end of the inner cylindrical body 14. In addition, at a position adjacent to the distal end side (the left side in FIG. 2) of the first protrusion 21, an annular second protrusion protruding outward in the radial direction with a protrusion amount smaller than that of the first protrusion 21. A portion 22 is formed.

  The outer cylinder 15 is formed in a cylindrical shape, and is disposed concentrically with the inner cylinder 14 on the radially outer side of the inner cylinder 14. A space (hereinafter also referred to as “insertion space”) S in which the pipe P can be inserted is formed between the inner peripheral surface of the outer cylindrical body 15 and the outer peripheral surface of the inner cylindrical body 14. . The outer peripheral surface of the distal end portion of the outer cylindrical body 15 is formed as a tapered surface 24 whose outer diameter increases toward the proximal end side. An annular holding recess 25 for accommodating a holding ring 42 described later is formed on the inner peripheral surface of the distal end portion of the outer cylindrical body 15. The holding recess 25 is disposed at a position overlapping the radially outer side of the notch groove 17 and the mounting groove 18 formed in the inner cylinder 14.

  The nut (screw cylinder) 16 is formed integrally with the base end portion of the outer cylinder body 15. That is, the nut 16 and the outer cylindrical body 15 are configured by a single component by machining one material. The outer peripheral surface 27 of the nut 16 is formed in a hexagonal shape into which a tool such as a spanner can be fitted, and a female screw 28 is formed on the inner peripheral surface. In addition, an annular third protrusion 29 that protrudes radially inward is formed on the tip end side of the nut 16. In addition, the screw cylinder 16 can also be made into the form which has an external thread in an outer peripheral surface according to the shape of the to-be-connected location U1 at the apparatus U side.

  The inner cylindrical body 14 is inserted into the nut 16 from the base end side (right side in FIG. 2) of the nut 16, and further protrudes toward the distal end side (left side in FIG. 2) from the nut 16 to the inside of the outer cylindrical body 15. Be placed. At this time, the first protrusion 21 of the inner cylinder 14 abuts against the third protrusion 29 of the nut 16 in the axial direction, thereby restricting the movement of the inner cylinder 14 relative to the nut 16 toward the tip side. Yes. Therefore, the first protrusion 21 of the inner cylinder 14 and the third protrusion 29 of the nut 16 constitute a position restricting portion 31 for restricting the movement of the inner cylinder 14 relative to the nut 16 to the tip side. is doing.

In addition, the 2nd protrusion part 22 formed in the inner cylinder 14 has a function as a stopper which sets the insertion limit of the pipe | tube P with respect to the insertion space S. As shown in FIG.
Further, an annular packing 33 is provided inside the nut 16, and this packing 33 is sandwiched between the base end surface of the inner cylinder 14 and the tip end surface of the connected portion U <b> 1 on the device U side. , Preventing fluid leakage between the two. Further, when the pipe joint 10 is not used or in a state where only the pipe P is connected to the pipe joint 10, the movement of the inner cylindrical body 14 relative to the nut 16 is not limited, and as shown in FIG. 6. A cap 34 is attached to the nut 16 to limit the movement of the inner cylindrical body 14 toward the proximal end side.

(Configuration of Elastic Seal Member 36)
FIG. 3 is an enlarged cross-sectional view showing a mounting portion of the elastic seal member 36 and the holding ring 42 in the pipe joint 10, and FIG. 4 is a cross-sectional view of the elastic seal member 36.
An annular elastic seal member 36 is mounted in the mounting groove 18 formed in the inner cylindrical body 14. The elastic seal member 36 is made of an elastically deformable material such as fluorine rubber. The axial width of the elastic seal member 36 is the same as or slightly smaller than the axial width of the mounting groove 18. The inner peripheral side of both axial end portions of the elastic seal member 36 is chamfered in an arc shape.

  On the outer peripheral surface of the elastic seal member 36, two annular seal portions 38a and 38b bulging in an arc shape radially outward are formed side by side in the axial direction. The seal portions 38 a and 38 b protrude outward in the radial direction from the inner peripheral surface of the inner cylindrical body 14 in a state of being inserted into the mounting groove 18. These seal portions 38a and 38b have a function of preventing fluid leakage between the inner cylindrical body 14 and the pipe P by being in close contact with the inner peripheral surface of the pipe P inserted into the insertion space S. is doing.

  A flat surface 40 substantially parallel to the central axis O is formed on the base end side (the right side in FIG. 3) of the elastic seal member 36. The flat surface 40 serves as a mark indicating the mounting direction of the elastic seal member 36 with respect to the mounting groove 18. Specifically, in the present embodiment, the elastic seal member 36 is mounted in the mounting groove 18 so that the flat surface 40 is positioned on the proximal end side.

  The elastic seal member 36 of the present embodiment has a configuration in which two seal portions 38a and 38b are integrally provided in the axial direction, but the two seal portions 38a and 38b are formed separately and are mutually connected. It may be an independent configuration. For example, the elastic seal member 36 may be configured by arranging two O-rings or the like constituting one seal portion side by side in the axial direction.

(Configuration of holding ring 42)
FIG. 5A is a cross-sectional view of the retaining ring 42, and FIG. 5B is a front view of the retaining ring 42.
As shown in FIGS. 3 and 5, a holding ring 42 is accommodated in the holding recess 25 formed on the inner peripheral surface of the outer cylinder 15. The holding ring 42 is formed in a C-shape with a circumferential portion 43 missing, and the radial dimension can be reduced by elastically deforming the gap between the missing portions 43. . Further, the holding ring 42 can be attached to the holding recess 25 by being inserted from the front end opening of the outer cylindrical body 15 with the radial dimension reduced.

  As shown in FIG. 3, a first claw portion (first holding portion) 46 that protrudes inward in the radial direction is formed at the axial front end portion (left end portion in FIG. 2) of the inner peripheral surface of the holding ring 42. In addition, a second claw portion (second holding portion) 45 protruding inward in the radial direction is formed at the axial base end portion (right end portion in FIG. 2). The first claw portion 46 and the second claw portion 45 have a function of holding the pipe P firmly by being pressed against the outer peripheral surface of the pipe P by reducing the radial dimension of the holding ring 42. ing.

  A first inclined surface 49 is formed at the distal end in the axial direction on the outer peripheral surface of the retaining ring 42 so as to be inclined so that the outer diameter increases toward the base end side (right side in FIG. 3). Further, a second inclined surface 48 that is inclined so that the outer diameter increases toward the proximal end side is formed on the proximal end side with respect to the first inclined surface 49. Therefore, the first and second inclined surfaces 49 and 48 are formed so that the radial distance between the outer peripheral surface of the tube P inserted into the insertion space S becomes narrower toward the distal end side. Further, a first step surface 50 is formed between the first inclined surface 49 and the second inclined surface 48, and the first step surface 50 is formed substantially parallel to the central axis O.

  The first inclined surface 49 and the second inclined surface 48 are formed at substantially the same inclination angle. Further, the first inclined surface 49 and the second inclined surface 48 are arranged apart from each other in the axial direction with the first step surface 50 interposed therebetween. Note that the base end side of the outer peripheral surface of the retaining ring 42 further than the second inclined surface 48 is an inclined surface 52 whose outer diameter decreases toward the base end side. Since the outer diameter of the base end side of the holding ring 42 is reduced by the inclined surface 52, the holding ring 42 can be easily inserted from the distal end opening of the outer cylindrical body 15, and can be easily attached to the holding recess 25. become able to.

  The bottom surface of the holding recess 25 formed in the outer cylindrical body 15 is inclined at substantially the same angle as the first inclined surface 49 of the holding ring 42, the third inclined surface 54 that contacts the first inclined surface 49, and the holding It has a fourth inclined surface 53 that is inclined at substantially the same angle as the second inclined surface 48 of the ring 42 and abuts against the second inclined surface 48. A second step surface 55 substantially parallel to the central axis O is formed between the third inclined surface 54 and the fourth inclined surface 53.

  In a direction (arrow X) in which the pipe P is inserted into the insertion space S between the outer cylindrical body 15 and the inner cylindrical body 14 and is separated from the insertion space S by the pressure of the fluid flowing inside the pipe P. When the force acts, the holding ring 42 moves to the tip side together with the pipe P, and is pushed radially inward by the outer cylinder 15 by the action of the first to fourth inclined surfaces 49, 48, 54, 53. , The radial dimension is reduced. Then, by reducing the radial dimension of the retaining ring 42, the first claw portion 46 and the second claw portion 45 are more strongly pressed against the outer peripheral surface of the tube P, and the tube P is reliably detached from the insertion space S. Is prevented. In particular, the holding ring 42 is pushed radially inward at two locations of the first and second inclined surfaces 49 and 48 on both sides in the axial direction. Can be strongly pressed against the surface.

  Here, the first to fourth inclined surfaces 49, 48, 54, 53 constitute an action part that reduces the radial dimension of the holding ring 42 by the movement of the pipe P in the separation direction X, and this action part and the holding part The ring 42 constitutes a holding mechanism 47 that holds the pipe P inserted into the insertion space S. In addition, the action portion is a first action surface configured by a set of a first inclined surface 49 and a third inclined surface 54, and a second set of a second inclined surface 48 and a fourth inclined surface 53. It consists of a working surface.

  In addition, the action part may be constituted by only the first inclined surface (first action surface) 49 and the second inclined surface (second action surface) 48 formed in the holding ring 42, and in this case, the holding recess It is only necessary that a portion (for example, a corner) that contacts the first inclined surface 49 and the second inclined surface 48 be present on the bottom surface of 25. On the contrary, the action part may be constituted only by the third inclined surface (first action surface) 54 and the fourth inclined surface (second action surface) 53, and in this case, the outer peripheral surface of the holding ring 42 In addition, it is sufficient if there are portions (for example, corners) that are in contact with the third inclined surface 54 and the fourth inclined surface 53, respectively.

When the strength of the tube P deteriorates with long-term use, the tube P tends to be detached from the insertion space S. However, as described above, the holding ring 42 causes the tube P to move away from the insertion space S by the movement of the tube P in the direction X. Since the tube P is firmly held, the separation of the tube P is reliably prevented.
Further, the elastic seal member 36 is deteriorated by long-term use, and permanent set is generated as the elastic force is reduced. This permanent distortion causes a decrease in the surface pressure of the elastic seal member 36 with respect to the inner peripheral surface of the pipe P, which causes fluid leakage. In this embodiment, the second claw portion 45 of the holding ring 42 is disposed at a position facing the radially outer side of the elastic seal member 36 in this embodiment, so that the radial dimension of the holding ring 42 is reduced. When the second claw portion 45 is strongly pressed against the outer peripheral surface of the pipe P, the inner peripheral surface of the pipe P is strongly pressed against the elastic seal member 36, and the seal surface pressure by the elastic seal member 36 is increased. Therefore, even if permanent deformation occurs in the elastic seal member 36, the function of the elastic seal member 36 can be maintained.

  Further, the first claw portion 46 of the retaining ring 42 is disposed at a position facing the radially outer side of the cutout groove 17 of the inner cylindrical body 14. For this reason, when the radial dimension of the retaining ring 42 is reduced and the first claw portion 46 is strongly pressed against the outer peripheral surface of the pipe P, the inner peripheral surface of the pipe P is the edge (locking portion) 56 of the notch groove 17. The edge 56 bites into the inner peripheral surface of the pipe P and is locked. Thereby, the holding force of the pipe P by the holding ring 42 is increased, and the detachment of the pipe P from the insertion space S is more reliably prevented.

Although the pipe joint 10 demonstrated above inserts the pipe P in the insertion space S from the insertion port 11, it connects the pipe P and the apparatus U by screwing the nut 16 in the connection location U1 of the apparatus U. In this case, the pipe joint 10 may be connected to the pipe P first, or may be connected to the device U first.
In the former case, for example, as shown in FIG. 2, when the nut 16 is rotated for connection to the device U in a state where the pipe P is inserted into the insertion space S of the pipe joint 10, the nut 16 is integrally formed. The outer cylinder 15 is also rotated. On the other hand, the inner cylinder 14 is only restricted to move toward the distal end side by the position restricting portion 31 with respect to the nut 16 and the outer cylinder 15, and is rotatable relative to the nut 16 and the outer cylinder 15. Therefore, the stopped state is maintained without being rotated with the rotation of the nut 16.

  Further, since the holding ring 42 pressed against the pipe P is only in contact with the bottom surface of the holding recess 25 of the outer cylinder 15, even if the outer cylinder 15 rotates with the nut 16, the holding ring 42. Does not slide along the bottom surface of the holding recess 25, and the pipe P is also kept stopped. Accordingly, only the outer cylinder 15 rotates together with the nut 16, and the pipe P is not kinked with the rotation of the nut 16, and the elastic seal member 36 is not excessively rubbed and damaged. Therefore, the sealing performance by the elastic seal member 36 can be suitably maintained.

  In the latter case, not only when the nut 16 of the pipe joint 10 is screwed into the connected portion U1 on the equipment U side, but also when the pipe P is inserted into the insertion space S of the pipe joint 10 thereafter, the pipe P The elastic seal member 36 is hardly damaged by rubbing against the pipe P. Therefore, the pipe P and the device U can be connected without any problem.

  The pipe joint 10 of the present embodiment is assembled by inserting the inner cylindrical body 14 from the proximal end side of the nut 16 toward the distal end side and arranging the inner cylindrical body 14 inside the outer cylindrical body 15. And the movement to the front end side of the inner cylinder 14 with respect to the nut 16 is restrict | limited by making the 3rd protrusion 29 of the nut 16 and the 1st protrusion 21 of the inner cylinder 14 contact | abut in an axial direction. The Therefore, the retaining C-ring 220 as in the prior art shown in FIG. 22 is unnecessary, and the pipe joint 22 can be assembled very easily and the number of parts can be reduced.

As shown in FIG. 3, the first and second inclined surfaces 49 and 48 formed in the holding ring 42 and the third and fourth inclined surfaces 54 and 53 formed in the holding recess 25 are both in between. First and second step surfaces 50 and 55 are interposed. This has the following advantages.
For example, if the first step surface 50 is omitted and the first inclined surface 49 is extended to the base end side as it is and continues to the second inclined surface 48, the first and second inclined surfaces 49, 48 are radially outward. The holding ring 42 is formed thicker in the radial direction. When the holding ring 42 is formed thick in the radial direction, there is a disadvantage that the weight increases and the rigidity becomes high, so that the mounting to the holding recess 25 becomes difficult. Similarly, when the second step surface 55 of the holding recess 25 is omitted and the third inclined surface 54 is extended as it is to the base end side and is continued to the fourth inclined surface 53, the holding recess 25 is moved radially outward. It will be deeply formed. Accordingly, the radial dimension of the outer cylinder 15 must be increased, and the pipe joint 10 is increased in size. When the holding recess 25 is deepened, the holding ring 42 must naturally be formed thicker in the radial direction.

In this regard, in the present embodiment, a first step surface 50 is formed between the first inclined surface 49 and the second inclined surface 48, and between the third inclined surface 54 and the fourth inclined surface 53. Since the second step surface 55 is formed, the holding ring 42 can be formed in a wide axial range without increasing the radial thickness of the holding ring 42 and without forming the holding recess 25 so deep. The tube P can be strongly pressed against the outer peripheral surface.
Note that the first and second step surfaces 50 and 55 are not limited to surfaces parallel to the central axis O of the pipe joint 10, but are more gentle than the first to fourth inclined surfaces 49, 48, 54, and 53. Thus, it is possible to use a surface inclined in the same direction as these or a surface inclined in the opposite direction to the first to fourth inclined surfaces 49, 48, 54, 53.

(Dimension setting of the first and second seal portions 38a and 38b in the elastic seal member 36)
In the elastic seal member 36 shown in FIG. 4, the diameter da of one seal portion (first seal portion) 38a disposed on the proximal end side and the other seal portion 38b (second seal portion) disposed on the distal end side. ) Is different from the diameter db. Specifically, in the present embodiment, the diameter da of the first seal portion 38a on the proximal end side is set larger than the diameter db of the second seal portion 38b on the distal end side.

  The compression amount (compression ratio) of the first and second seal portions 38a and 38b when the first and second seal portions 38a and 38b are in close contact with the inner peripheral surface of the pipe P by having different diameters. Are different from each other, and the sealing performance by the elastic sealing member 36 is enhanced. Hereinafter, this point will be described in detail.

  The elastic seal member 36 used in the pipe joint 10 prevents fluid leakage by the surface pressure (seal surface pressure) generated by the compression when it is in close contact with the pipe P. 36 needs to be compressed. On the other hand, when the elastic seal member 36 is compressed over a long period of time, the seal surface pressure decreases due to permanent distortion. Such permanent set tends to increase as the initial compression amount of the elastic seal member 36 increases. Therefore, if the compression amount of the elastic seal member 36 is increased from the beginning of the construction, even if the initial fluid leakage can be reliably suppressed, the possibility of fluid leakage after a long period of use increases. If the amount of compression of the elastic seal member 36 at the beginning of the construction is reduced, there is a problem that even if the fluid leakage after use for a long time can be suppressed, the initial leakage is likely to occur. Therefore, in order to prevent both the initial fluid leakage and the fluid leakage after long-term use, it is necessary to keep the compression amount of the elastic seal member 36 within a limited and appropriate range.

  FIG. 7 is a graph showing the relationship between the compression rate of the elastic seal member 36 and the permanent set rate after long-term use. In this graph, the horizontal axis represents the compression rate of the elastic seal member 36, and the vertical axis represents the permanent distortion rate. The compression rate Cr is in close contact with the pipe P, where d is the thickness (wire diameter) of the elastic seal member 36 in an uncompressed state (the state before use) as shown in FIG. Assuming that the amount of compression at this time is a, it can be expressed as Cr = a / d. Further, the permanent distortion rate Dr can be expressed as Dr = b / a, where b is the amount of change in thickness (wire diameter) when the elastic seal member 36 is compressed for a long time and then the compression is released.

  From the graph of FIG. 7, the permanent set rate of the elastic seal member 36 shows a relatively low value when the compression rate is in a range of approximately 0.1 to 0.25, and is large even if the compression rate is smaller than the range. However, the permanent set rate tends to increase. Therefore, in the present embodiment, the lower limit compression rate of the elastic seal member 36 is set to 0.1, the upper limit compression rate is set to 0.25, and the range between these is set to the recommended range of the compression rate.

  By the way, the inner and outer diameter dimensions and thickness dimensions of the elastic seal member 36 itself, the outer diameter dimension of the mounting groove 18 of the inner cylindrical body 14 to which the elastic seal member 36 is mounted, the inner diameter dimension of the pipe P closely contacting the elastic seal member 36, etc. Of course, there is a manufacturing error, and an allowable manufacturing error, that is, a tolerance, is set for each of the parts 36, 14, and P. However, even if the respective parts 36, 14, and P are manufactured within the tolerance range, the compression ratio that the elastic seal member 36 can take by combining the tolerances of the respective parts 36, 14, and P becomes a wide range. It is difficult to keep within the recommended range.

  For example, as shown in FIG. 8, the diameter of the elastic seal member 36 is set so that the minimum compression rate of the elastic seal member 36 that can be taken within the tolerance range of the components 36, 14, and P is equal to or greater than the lower limit compression rate. When the directional dimension is set, the maximum compression rate of the elastic seal member 36 that can be taken within the range of the tolerance may exceed the upper limit compression rate (refer to the graph of □ in FIG. 8). Conversely, when the radial dimension of the elastic seal member 36 is set so that the maximum compression rate of the elastic seal member 36 that can be taken within the tolerance range of the parts 36, 14, and P is equal to or less than the upper limit compression rate, In some cases, the minimum compression rate of the elastic seal member 36 that can be taken within the range of the tolerance is smaller than the lower limit compression rate (see the graph indicated by ● in FIG. 8).

Therefore, in the present embodiment, within the tolerance range of the parts 36, 14, and P, one of the two seal portions 38a and 38b is always equal to or higher than the lower limit compression rate, and the other is always equal to or lower than the upper limit compression rate. Thus, the radial dimension of each seal portion 38a, 38b of the elastic seal member 36 is set.
Specifically, in the first seal portion 38a having a larger outer diameter, the inner and outer diameter dimensions are such that the compression ratio is always equal to or less than the upper limit compression ratio within the tolerance range of the radial dimension of each component 36, 14, P. (Thickness dimension) is set, and in the second seal portion 38b having a smaller outer diameter, the compression ratio is always equal to or greater than the lower limit compression ratio within the tolerance of the radial dimension of each component 36, 14, P. Inner and outer diameter dimensions (thickness dimensions) are set so as to be. By setting the radial dimensions of the seal portions 38a and 38b in this manner, it is possible to appropriately suppress both initial fluid leakage and fluid leakage after long-term use.

(Verification of effects related to seal portions 38a and 38b)
The applicant of the present application verified the effects related to the above-described seal portions 38a and 38b by the method described below.
First, as shown in Table 1 below, assuming the three types of O-rings (large diameter, medium diameter, and small diameter) having different wire diameters as the elastic seal member 36, the outer diameter described in the above embodiment is used. Instead of the elastic seal member 36 having two different seal portions 38a and 38b, one small-diameter O-ring and one large-diameter O-ring are combined to form an embodiment of the present invention. Moreover, the example which used 1-3 O-rings of medium diameter in combination was made into the prior art. Then, the occurrence rates of the initial fluid leakage and the fluid leakage after long-term use were determined in each case of the example and the prior art.

The outer diameter dimension and tolerance of the mounting groove 18 of the inner cylindrical body 14 to which the O-ring (elastic seal member) is mounted, the inner diameter dimension and tolerance of the pipe P in close contact with the O-ring, and the inner diameter dimension of each type of O-ring The tolerance was defined as shown in Table 1 (unit: mm). The wire diameter of the O-ring is shown in three stages: small diameter, large diameter, and medium diameter.
The variation in dimensions of the O-ring wire diameter and inner diameter, the outer diameter of the mounting groove 18 and the inner diameter of the pipe P is assumed to be normally distributed, and ± 3σ (σ is the standard deviation) is assumed to be within the tolerance range. Assuming that fluid leakage does not occur when the compression ratio of each O-ring is in the range of 0.1 to 0.25, and fluid leakage occurs when the compression rate is outside this range, the fluid leakage occurrence rate is Obtained by calculation.
Table 2 shows the results.

  First, in the case of using one medium-diameter O-ring as the prior art, the initial fluid leakage rate was 419 (ppm: parts per million), whereas the fluid after long-term use. The leakage occurrence rate of was 453 (ppm). Similarly, in the case of using two medium-diameter O-rings, the leak occurrence rates of the fluid after initial and long-term use are 130 (ppm) and 152 (ppm), respectively, and three medium-diameter O-rings are used. In the case of using, the leak occurrence rates of the fluid after the initial and long-term use were 40 (ppm) and 51 (ppm), respectively. From the above results, it can be seen that the rate of fluid leakage decreases as the number of O-rings used increases. It can also be seen that the fluid leakage rate after long-term use is higher than the initial fluid leakage rate.

  In contrast, in the embodiment of the present invention in which one small O-ring and one large O-ring are used, the initial fluid leakage rate is 31 (ppm), and the fluid after long-term use. The leak occurrence rate was 31 (ppm). Therefore, not only the case of the prior art using two medium-diameter O-rings, but also the leakage occurrence rate is lower than the case using three medium-diameter O-rings. It can be seen that the effect of suppressing fluid leakage is extremely high. It can also be seen that there is no change in the leak rate between the initial stage and after long-term use.

(Application example of pipe joint 10)
10 to 12 show various devices to which the pipe joint 10 of the present invention can be applied.
FIG. 10 is a configuration diagram schematically showing the hot water supply device 80, and the hot water supply device 80 includes a heat source unit 57 and a water storage unit 58, both of which are connected by a communication pipe 59. Further, the water storage unit 58 is connected to a hot water supply device (hot water utilization device) 60 such as a bathtub by a connection pipe 59.

The heat source unit 57 is a so-called heat pump unit, and has a function of heating the water supplied from the water storage unit 58 via the communication pipe 59 by the refrigeration cycle and returning the water to the water storage unit 58 in a heated state. The heat source unit 57 includes a refrigerant circuit through which the refrigerant flows. In this refrigerant circuit, heat is exchanged with the water supplied from the water storage unit 58 after the low-temperature and low-pressure refrigerant is heat-exchanged with the outside air to evaporate and the evaporated high-temperature refrigerant is compressed. Condensates the refrigerant and heats the water. Then, the condensed refrigerant is decompressed by the expansion valve, and the refrigeration cycle for exchanging heat with the outside air is repeated. In the refrigerant circuit, for example, CO ₂ refrigerant is used as the refrigerant, and hot water of 90 ° C. or higher can be generated by the CO ₂ refrigerant. The heat source unit 57 may also have a function of cooling water by reverse circulation of the refrigerant.

  The water storage unit 58 has a function of sending water supplied from a water source such as a water pipe to the heat source unit 57, storing hot water generated in the heat source unit 57 in a water storage tank, and further sending the stored hot water to the hot water supply device 60. have.

  A water stop valve 63 is provided at the entrance of water (hot water) in the heat source unit 57 and the water storage unit 58. The pipe joint 10 of the present embodiment is used to connect the connecting pipe 59 as the pipe P and the water stop valve 63 (the connected portion U1) in the heat source unit 57 and the water storage unit 58 as the equipment U. Yes. Further, a water stop valve 63 is also provided at the water entrance / exit of the hot water supply device 60, and the pipe joint 10 of the present embodiment is used to connect the water stop valve 63 and the communication pipe 59. In addition, the pipe joint 10 of this Embodiment may be used with respect to either of the connection parts of the multiple places of the water stop valve 63 and the connection piping 59. FIG.

Since the heat source unit 57 using the CO ₂ refrigerant can generate very high temperature hot water of 90 ° C. or higher, it is recommended to use a hard resin pipe or a three-layer pipe having high heat resistance as the connection pipe 59. ing. In the case of using these pipes, it is extremely effective to use the pipe joint 10 of the present embodiment, which has a high effect of preventing the above-described pipe detachment and a high effect of preventing fluid leakage due to long-term use.

  FIG. 11 is a configuration diagram schematically showing the air conditioner 81, and the air conditioner 81 includes a heat source unit 66, a water storage unit 67, and an air conditioner unit 68. The heat source unit 66 and the water storage unit 67 have substantially the same configuration as the heat source unit 57 and the water storage unit 58 in the hot water supply device 80. The air conditioning unit 68 performs heat exchange with indoor air using the cold / hot water generated by the heat source unit 66 as a refrigerant, and adjusts the indoor temperature and humidity. A water stop valve 63 is provided in the heat source unit 66, the water storage unit 67, and the air conditioning unit 68 at a water (hot water) entrance / exit, or at a midway position of a predetermined connection pipe 59. The heat source unit 66 and the water storage unit 67 are connected by a communication pipe 59, and the water storage unit 67 and the air conditioning unit 68 are connected by a communication pipe 59. Further, a pump 65 is provided at an appropriate location of the communication pipe 59.

  And the pipe joint 10 of this Embodiment can be used with respect to either or all of the connection parts with the water stop valve 63 provided in each unit 66-68 or the connection piping 59, and the connection piping 59. FIG.

  FIG. 12 is a configuration diagram schematically showing the floor heating device 82, and the floor heating device 82 includes a heat source unit 70 and a floor heating unit 71. The heat source unit 70 has substantially the same configuration as the heat source unit 57 of the hot water supply device 80. The floor heating unit 71 includes a floor heating panel 73 that is buried under the floor of the room and has a heat radiating pipe 72 through which hot water flows. The heat source unit 70 and the heat radiating pipe 72 of the floor heating panel 73 are connected by a communication pipe 59, the connection portion between the water stop valve 63 and the communication pipe 59 of the heat source unit 70, and the floor heating panel 73 and the communication pipe 59. The pipe joint 10 of the present embodiment can be used for any or all of the connecting portions.

<< Second Embodiment >>
FIG. 13 is a cross-sectional view of the pipe joint 10 according to the second embodiment of the present invention.
The pipe joint 10 of the present embodiment is slightly different from the pipe joint 10 of the first embodiment in the configuration of the outer cylinder 15. Specifically, the outer cylinder 15 in the present embodiment includes a first cylinder portion 74 disposed on the base end side (right side in FIG. 13) and a second cylinder portion disposed on the distal end side (left side in FIG. 13). It consists of a cylindrical part 75. A male screw 74a is formed on the outer peripheral surface of the distal end portion of the first cylindrical portion 74, and a female screw 75a is formed on the inner peripheral surface of the proximal end portion of the second cylindrical portion 75. The first cylinder portion 74 and the second cylinder portion 75 are coupled by screwing the screw 75a. Further, the holding recess 25 for accommodating the holding ring 42 is formed on the inner peripheral surface of the second cylinder portion 75.

  About the other structure in the pipe joint 10 of this Embodiment, it is the same as that of 1st Embodiment. Therefore, the pipe joint 10 of the present embodiment also has the same operational effects as the first embodiment. Furthermore, in the pipe joint 10 of the present embodiment, the outer cylinder 15 is configured by the first cylinder part 74 and the second cylinder part 75, and the holding recess 25 is formed in the second cylinder part 75. The second cylinder portion 75 can be screwed into the first cylinder portion 74 in a state where the holding ring 42 is accommodated in the holding recess 25. This eliminates the need to insert the holding ring 42 from the front end opening of the outer cylinder 15 with the radial dimension of the holding ring 42 reduced as in the first embodiment, and facilitates the outer cylinder. The retaining ring 42 can be attached to the 15.

<< Third Embodiment >>
FIG. 14 is a cross-sectional view of the pipe joint 10 according to the third embodiment of the present invention.
In the pipe joint 10 of the present embodiment, the outer cylindrical body 15 and the nut 16 are formed as separate bodies and are configured to be integrally rotatable by being coupled to each other. Specifically, a male screw 16a is formed on the outer peripheral surface of the distal end side (left side in FIG. 14) of the nut 16 of the present embodiment, and the inner peripheral surface on the proximal end side (right side in FIG. 14) of the outer cylinder 15 Is formed with a female screw 15a, and the nut 16 and the outer cylinder 15 are integrally coupled by screwing the male screw 16a and the female screw 15a. About the other structure in the pipe joint 10 of this Embodiment, it is the same as that of 1st Embodiment, Therefore, also in the pipe joint 10 of this Embodiment, the effect similar to 1st Embodiment is obtained. Play. The outer cylinder 15 and the nut 16 are not limited to being coupled by screwing the male screw 16a and the female screw 15a, but may be coupled by other means such as press fitting.

<< Fourth Embodiment >>
FIG. 15 is a cross-sectional view of the pipe joint 10 according to the fourth embodiment of the present invention.
The pipe joint 10 of the present embodiment is different from the pipe joint 10 of the first embodiment in the arrangement of the retaining ring 42 and the notch groove 17. Specifically, a holding recess 25 is formed on the outer peripheral surface of the inner cylindrical body 14 on the base end side with respect to the mounting groove 18, and the holding ring 42 is accommodated in the holding recess 25. The holding ring 42 includes a first claw portion 46 and a second claw portion 45 on its outer peripheral surface, and the diameter of the holding ring 42 at the bottom surface of the holding recess 25 by the movement of the tube P in the direction X to be removed from the insertion space S. The radial dimension is enlarged by being pushed outward in the direction, and the first claw portion 46 and the second claw portion 45 are pressed against the inner peripheral surface of the pipe P so as to hold the pipe P firmly. Yes.

A notch groove 17 is formed on the inner peripheral surface of the outer cylindrical body 15. The cutout groove 17 is formed at a position facing the radially outer side of the first claw portion 46 of the holding ring 42. For this reason, when the radial dimension of the retaining ring 42 is enlarged and the first claw portion 46 is strongly pressed against the inner peripheral surface of the pipe P, the outer peripheral surface of the pipe P is the edge (locking portion) 56 of the notch groove 17. The edge 56 bites into the inner peripheral surface of the pipe P and is locked. Thereby, the holding force of the pipe P by the holding ring 42 is increased, and the detachment of the pipe P from the insertion space S is more reliably prevented.
However, in this embodiment, since the holding ring 42 is provided on the inner cylinder 14 together with the elastic seal member 36, the holding ring 42 is pressed against the pipe P as in the pipe joint 10 of the first embodiment. As a result, the effect of increasing the surface pressure of the elastic seal member 36 cannot be achieved. Therefore, in this respect, the first embodiment is more advantageous than the present embodiment.

<< Fifth Embodiment >>
FIG. 16 is a cross-sectional view of the pipe joint 10 according to the fifth embodiment of the present invention.
The pipe joint 10 of the present embodiment is different from the third embodiment (see FIG. 14) in that the outer cylinder body 15 and the nut 16 are formed separately and are coupled to each other so as to be integrally rotatable. This is the same as that of the fourth embodiment (see FIG. 15) in that the holding ring 42 is provided in the inner cylinder 14 and the notch groove 17 is provided in the outer cylinder 15. Therefore, with respect to the configuration common to the present embodiment and the third and fourth embodiments, the same effects are obtained.

<< Sixth Embodiment >>
FIG. 17 is a cross-sectional view of the pipe joint 10 according to the sixth embodiment of the present invention.
The pipe joint 10 of the present embodiment is not configured such that the outer cylinder 15 and the nut 16 are integrally rotatable as in the first to fifth embodiments described above, but the outer cylinder 15 The inner cylindrical body 14 is configured to be integrally rotatable, and the outer cylindrical body 15 and the inner cylindrical body 14 and the nut 16 are configured to be relatively rotatable.
More specifically, a male screw 14 b is formed on the outer peripheral surface of the second protrusion 22 in the inner cylindrical body 14, and a female screw 15 b is formed on the inner peripheral surface of the base end portion of the outer cylindrical body 15. Has been. The outer cylinder 15 and the inner cylinder 14 are integrally coupled by screwing the male screw 14b and the female screw 15b.

  In the present embodiment, the pipe joint 10 is assembled as follows. First, the inner cylinder 14 separated from the outer cylinder 15 is inserted into the nut 16 from the base end side of the nut 16. At this time, the third protrusion 29 of the nut 16 and the first protrusion 21 of the inner cylinder 14 are brought into contact with each other in the axial direction, thereby restricting the movement of the inner cylinder 14 relative to the nut 16 toward the distal end. Is done. And the inner cylinder 14 which protruded from the nut 16 to the front end side is inserted into the outer cylinder 15, and the male screw 14b and the female screw 15b are screwed together. The base end surface of the outer cylinder 15 is slidably in contact with the distal end surface of the nut 16 and sandwiches the third protrusion 29 of the nut 16 between the first protrusion 21. Therefore, the relative axial movement of the outer cylinder 15, the inner cylinder 14, and the nut 16 is completely restricted.

  When the pipe joint 10 of the present embodiment is connected to the pipe P and then connected to the connected portion U1 of the device U, the nut 16 can rotate independently relative to the inner cylinder body 14 and the outer cylinder body 15. Therefore, the pipe P inserted into the insertion space S is not twisted and the elastic seal member 36 is not rubbed and damaged with the pipe P, and the pipe P and the device U are appropriately connected. Can do.

  The inner cylindrical body 14 is inserted from the proximal end side with respect to the nut 16, and the distal end side of the inner cylindrical body 14 with respect to the nut 16 by the position restricting portion 31 including the first protruding portion 21 and the third protruding portion 29. Therefore, the inner cylinder 14 and the outer cylinder 15 are easier to assemble than the pipe joint 10 according to the prior art shown in FIG. Since the C-ring or the like is unnecessary, the number of parts can be reduced.

<< Seventh Embodiment >>
FIG. 18 is a cross-sectional view of the pipe joint 10 according to the seventh embodiment of the present invention.
As with the pipe joint (see FIG. 17) according to the sixth embodiment, the pipe joint 10 of the present embodiment is configured such that the outer cylinder body 15 and the inner cylinder body 14 are integrally rotatable. The body 15 and the inner cylinder 14 and the nut 16 are configured to be relatively rotatable. In the present embodiment, as in the fourth embodiment (see FIG. 15), the holding recess 25 is formed on the outer peripheral surface of the inner cylindrical body 14 and on the base end side of the mounting groove 18. A holding ring 42 having a first claw portion 46 and a second claw portion 45 is accommodated in the holding recess 25. Further, a notch groove 17 is formed on the inner peripheral surface of the outer cylindrical body 15, and the notch groove 17 is formed at a position facing the radially outer side of the first claw portion 46 of the holding ring 42. For this reason, when the radial dimension of the retaining ring 42 is enlarged and the first claw portion 46 is strongly pressed against the inner peripheral surface of the pipe P, the outer peripheral surface of the pipe P is the edge (locking portion) 56 of the notch groove 17. The edge 56 bites into the inner peripheral surface of the pipe P and is locked. Thereby, the holding force of the pipe P by the holding ring 42 is increased, and the detachment of the pipe P from the insertion space S is more reliably prevented.

<< Eighth Embodiment >>
FIG. 19 is a cross-sectional view of the pipe joint 10 according to the eighth embodiment of the present invention.
As with the pipe joint (see FIG. 17) according to the sixth embodiment, the pipe joint 10 of the present embodiment is configured so that the outer cylinder 15 and the inner cylinder 14 can rotate integrally, and the outer cylinder body. 15 and the inner cylinder 14, and the nut 16 are comprised so that relative rotation is possible. And in this Embodiment, the outer cylinder 15 and the inner cylinder 14 are comprised as a single component by machining one raw material.

  Further, the outer cylindrical body 15 can be inserted into the nut 16 from the base end side of the nut 16, and the first protrusion 21 constituting the position restricting portion 31 is radial from the base end portion of the outer cylindrical body 15. It is formed to protrude outward. Therefore, the movement of the outer cylinder 15 and the inner cylinder 14 to the tip side with respect to the nut 16 is restricted by the first protrusion 21 and the third protrusion 29 abutting in the axial direction.

  Other configurations are the same as those of the sixth embodiment, and the same operational effects as those of the sixth embodiment are achieved. Further, since the outer cylinder 15 and the inner cylinder 14 are integrally formed, the number of parts is further reduced, and the manufacturing cost can be reduced.

  In addition, also about each pipe joint 10 demonstrated in the above-mentioned 2nd-8th embodiment, each unit in the hot water supply apparatus 80, the air conditioning apparatus 81, and the floor heating apparatus 82 as shown in FIGS. Needless to say, the present invention can be applied to a connecting portion with a communication pipe.

The present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope of the invention described in the claims.
For example, in each of the embodiments described above, the elastic seal member 36 is provided on the outer peripheral surface of the inner cylindrical body 14, but the elastic seal member 36 may be provided on the inner peripheral surface of the outer cylindrical body 15. In this case, as a modification of the first to fifth embodiments, the nut 16 is provided so as to be integrally rotatable with respect to the inner cylinder 14 in a state where the nut 16 is rotatable relative to the outer cylinder 15. .

  The holding ring 42 may include a first claw portion (first holding portion) 46 and a second claw portion (second holding portion) 45 separately. That is, the holding ring 42 of the present invention may be configured by the first holding ring having the first claw portion 46 and the second holding ring having the second claw portion 45.

In each of the above embodiments, the first and second seal portions 38a and 38b of the elastic seal member 36 are formed to have different outer diameters. As shown in FIG. 20, the outer diameter and thickness (wire diameter) of the first and second seal portions 38a, 38b are the same, and the outer diameter of the mounting groove 18 in which the elastic seal member 36 is mounted (that is, By changing the depth of the mounting groove 18 in the axial direction, the compression rate (the amount of protrusion from the inner cylinder 14) of the first and second seal portions 38a and 38b may be varied. In FIG. 20, the elastic seal member 36 is constituted by two O-rings having the same shape, and the respective seal portions 38a and 38b are constituted by the respective O-rings.
Further, the number of seal portions of the elastic seal member 36 is not limited to two and may be three or more.

  The pipe joint 10 of the present invention can be used to connect the pipe P and the equipment U that handle gas as well as liquid.

10: Pipe joint 14: Inner cylinder 15: Outer cylinder 16: Nut (screw cylinder)
31: Position restricting part 36: Elastic seal member 38a: Seal part 38b: Seal part 42: Holding ring 45: Second claw part (second holding part)
46: 1st nail | claw part (1st holding | maintenance part)
47: Holding mechanism 48: Second inclined surface (second action surface)
49: First inclined surface (first action surface)
50: First step surface 53: Fourth inclined surface (second action surface)
54: Third inclined surface (first working surface)
55: 2nd level | step difference surface 56: Locking part 57: Heat source unit 58: Water storage unit 59: Connection piping 60: Hot-water supply equipment 63: Water stop valve (connection place)
66: Heat source unit 67: Water storage unit 68: Air conditioning unit 70: Heat source unit 71: Floor heating unit 80: Hot water supply device 81: Air conditioning device 82: Floor heating device P: Pipe U1: Connected part

Claims (19)

A pipe joint in which the distal end side in the axial direction is connected to the pipe (P) and the proximal end side in the axial direction is connected to the connected portion (U1),
An inner cylinder (14);
An outer cylinder (15) which is disposed on the radially outer side of the inner cylinder (14) and forms a space (S) into which the pipe (P) can be inserted between the inner cylinder (14);
The inner cylindrical body (14) and the outer cylindrical body (15) are provided so as to be integrally rotatable at the base end portion of the other cylindrical body while being relatively rotatable with respect to the one cylindrical body, and to be connected A screw cylinder (16) having a screw portion screwed onto (U1);
An elastic seal member (36) provided on the one cylinder and in close contact with the peripheral surface of the pipe (P) inserted in the space (S);
A holding mechanism (for holding the pipe (P) in a state in which relative rotation between the pipe (P) inserted into the space (S) and the other cylinder is allowed is provided on the one or other cylinder. 47)
A pipe joint characterized by comprising: The screw cylinder (16) is provided so as to be integrally rotatable at a base end portion of the outer cylinder (15) in a state of being rotatable relative to the inner cylinder (14),
The pipe joint according to claim 1, wherein the elastic seal member (36) is provided on an outer peripheral surface of the inner cylinder (14). The inner cylinder (14) is inserted into the outer cylinder (15) in the axial direction from the base end side of the screw cylinder (16),
The inner cylinder (14) and the screw cylinder (16) have a position restricting portion (31) that restricts axial movement of the inner cylinder (14) toward the distal end side with respect to the screw cylinder (16). The pipe joint according to claim 2, which is provided. A pipe joint in which the distal end side in the axial direction is connected to the pipe (P) and the proximal end side in the axial direction is connected to the connected portion (U1),
An inner cylinder (14);
The inner cylinder (14) is arranged on the outer side in the radial direction, is provided so as to be integrally rotatable with the inner cylinder (14), and a pipe (P) can be inserted between the inner cylinder (14). An outer cylinder (15) forming a large space (S);
A screw cylinder having a threaded portion that is coupled to a proximal end portion of the inner cylindrical body (14) and the outer cylindrical body (15) in a relatively rotatable state and is screwed into a connected portion (U1). (16) and
An elastic seal member (36) provided on one of the inner cylinder (14) and the outer cylinder (15) and in close contact with the peripheral surface of the pipe (P);
A holding mechanism (47) provided on one of the inner cylinder (14) and the outer cylinder (15) and holding the pipe (P) inserted into the space (S). ,
The inner cylinder (14), or the inner cylinder (14) and the outer cylinder (15) are arranged in the screw cylinder (16) from the proximal end side to the distal end side of the screw cylinder (16). Inserted in the axial direction,
The inner cylinder (14) or the outer cylinder (15) and the screw cylinder (16) include the inner cylinder (14) or the outer cylinder (15) with respect to the screw cylinder (16). A pipe joint characterized in that a position restricting portion (31) for restricting axial movement toward the distal end side is provided. The holding mechanism (47) is in contact with the peripheral surface of the tube (P) and the peripheral surface of the outer cylinder (15) or the inner cylinder (14) opposed to the outer surface in the radial direction, and the radial dimension is A retaining ring (42) configured to be reduced or enlarged;
An action part (48, 49, 53, 54) for reducing or enlarging the radial dimension of the holding ring (42) in order to press the holding ring (42) against the peripheral surface of the pipe (P). The pipe joint according to any one of claims 1 to 4.   The retaining ring (42) is provided with respect to the cylinder opposite to the cylinder provided with the elastic seal member (36), and at least a part of the holding ring (42) is in the radial direction of the elastic seal member (36). The pipe joint according to claim 5, wherein the pipe joint is pressed against the peripheral surface of the pipe (P) at the opposite position. The holding ring (42) is a first holding portion (46) that is pressed against the peripheral surface of the pipe (P) at a position deviated in the axial direction from a radial facing position of the elastic seal member (36);
A second holding portion (45) formed integrally with or separately from the first holding portion (46) and pressed against the circumferential surface of the pipe (P) at a radially opposing position of the elastic seal member (36); The pipe joint according to claim 6, comprising:   The cylindrical body provided with the elastic seal member (36) is provided with a locking portion (56) that bites into the peripheral surface of the tube (P) pressed by the first holding portion (46) and locks it. The pipe joint according to claim 7. The action part (48, 49, 53, 54)
A first working surface (49, 54) for pressing the first holding portion (46) against the peripheral surface of the pipe (P);
A second working surface (48, 53) for pressing the second holding part (45) against the peripheral surface of the pipe (P),
The first and second working surfaces (49, 54, 48, 53) are inclined surfaces that are inclined such that the radial distance from the peripheral surface of the pipe (P) becomes narrower toward the tip end side in the axial direction. The pipe joint according to claim 7 or 8, wherein the pipe joint is formed so as to be spaced apart via a step surface (50, 55). The elastic seal member (36) has at least two seal portions (38a, 38b) in the axial direction,
The pipe joint according to any one of claims 1 to 9, wherein the two seal portions (38a, 38b) have mutually different compression ratios due to close contact with the peripheral surface of the pipe (P). Of the two seal portions (38a, 38b), the seal portion (38b) having a smaller compressibility is the inner cylinder (14) or the outer cylinder (15) provided with the elastic seal member (36). The diameter of the pipe (P) and the seal part (38b) is such that they are pressed against the peripheral surface of the pipe (P) at a compression ratio equal to or higher than a predetermined lower limit compression ratio within a dimensional tolerance range in the radial direction. Direction dimension is set,
The radial dimension is set so that the seal portion (38a) having a higher compression rate is pressed against the peripheral surface of the pipe (P) at a compression rate equal to or lower than a predetermined upper limit compression rate within the tolerance. The pipe joint according to claim 10.   The pipe joint according to any one of claims 1 to 11, which is used for connection between a hard resin pipe or a metal reinforced resin pipe as a pipe (P) and a connected portion (U1).   The pipe joint according to any one of claims 1 to 12, which is used for connection between a pipe (P) through which a fluid that does not change phase at room temperature and a connected part (U1). A heat source unit (57) having a refrigerant circuit for generating hot water by a refrigeration cycle, a water storage unit (58) for storing hot water generated in the heat source unit (57), and hot water stored in the water storage unit (58) Piping for circulating hot water between the hot water supply device (60) for discharging water, the heat source unit (57) and the water storage unit (58), and between the water storage unit (58) and the hot water supply device (60) (59), a hot water supply device comprising:
A connecting portion between the heat source unit (57) and the connecting pipe (59), a connecting portion between the water storage unit (58) and the connecting pipe (59), and the hot water supply device (60) and the connecting pipe (59). The hot-water supply apparatus characterized by using the pipe joint of any one of Claims 1-13 for at least 1 connection part among connection parts. The hot water supply device according to claim 14, wherein a CO ₂ refrigerant is used in the refrigerant circuit of the heat source unit (57). A heat source unit (66) having a refrigerant circuit for generating cold / hot water by a refrigeration cycle, a water storage unit (67) for storing cold / hot water generated by the heat source unit (66), and the water storage unit (67). Between the heat source unit (66) and the water storage unit (67), between the water storage unit (67) and the air conditioning. A communication pipe (59) for circulating cold / hot water between the unit (68) and an air conditioner,
A connecting portion between the heat source unit (66) and the connecting pipe (59), a connecting portion between the water storage unit (67) and the connecting pipe (59), and the air conditioning unit (68) and the connecting pipe (59 The air-conditioning apparatus according to any one of claims 1 to 13, wherein the pipe joint according to any one of claims 1 to 13 is used for at least one of the connecting parts. The air conditioner according to claim 16, wherein a CO ₂ refrigerant is used in the refrigerant circuit of the heat source unit (66). A heat source unit (70) having a refrigerant circuit for generating hot water by a refrigeration cycle, a floor heating unit (71) for adjusting the temperature of the floor surface by the hot water generated by the heat source unit (70), and hot water between both units A floor heating device comprising a communication pipe (59) for circulating
The connection part between the heat source unit (70) and the communication pipe (59) and / or the connection part between the floor heating unit (71) and the communication pipe (59), according to any one of claims 1 to 13. A floor heating apparatus, wherein the pipe joint according to item 1 is used. The floor heating apparatus according to claim 18, wherein CO ₂ refrigerant is used in the refrigerant circuit of the heat source unit (70).

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