JP5560222B2 - Resin pipe fittings - Google Patents

Description

  The present invention is a resin pipe fitting, and more specifically, a resin suitable for piping of high-purity liquid or ultrapure water handled in manufacturing processes in various technical fields such as semiconductor manufacturing, medical / pharmaceutical manufacturing, food processing, chemical industry, etc. The present invention relates to a pipe joint.

  As a resin pipe joint (resin pipe joint structure) using a pipe insertion sleeve called an inner ring, a cylindrical threaded portion protruding from the joint body with a male screw formed on the outer periphery, and a radially outer side An inner ring for sealing having an annular large-diameter portion that is raised on the outer periphery and a union nut formed with a female screw that is screwed into the male screw are disclosed in Patent Document 1 and Patent Document 2. Is known.

  In other words, by fitting the tube to the inner ring with the tube forcedly fitted to the inner ring and pressing it in the axial direction with the union nut, the coupling body and fluid equipment can be connected to the tube without fluid leakage. In the field, it is an excellent one that can achieve a great effect that it is easy to insert and tighten the union nut after inserting the inner ring with the tube into the cylindrical threaded portion. is there.

  As an example of on-site piping connection work using this resin pipe joint, insert the inner ring with the inner ring into which the inner ring is forcibly press-fitted in advance, and insert the inner ring into the cylindrical threaded portion. Insert the tube end into the fitting body, and then tighten the union nut fitted in the tube by screwing the female screw into the male screw of the cylindrical threaded part. The joining to the joint body is completed.

  That is, since the seal portion is finally established by tightening the union nut, a corresponding tightening torque is required. In many cases, since the turning operation is performed using a tool such as a spanner, it is necessary to make an effort for the replacement accompanying the assembly or fluid replacement of the resin pipe joint. In addition, since it is difficult to use tools in narrow locations, extra time is required and accurate visual inspection of the finish is difficult, and metal tools cannot be used when working in a clean room. There is also a problem that the replacement work becomes more difficult.

Japanese Patent Laid-Open No. 10-054489 Japanese Utility Model Publication No. 02-117494

  An object of the present invention is to provide an improved resin pipe joint that is easy to assemble while maintaining the conventional sealing performance and can be appropriately installed by taking into account the conventional situation described above. In the point.

The invention according to claim 1 is a resin pipe joint,
A synthetic resin cylindrical portion 1A having the engaging portion 7 and provided in the joint body 1 or the fluid device 1, and a synthetic resin inner ring 3 provided with a large diameter portion 3b protruding outward in the outer diameter portion 3G. And a union cylinder 2 made of a synthetic resin that includes an engaged portion 13 that can be engaged with the engaging portion 7 and can be externally mounted on the cylindrical portion 1A.
The circumferential protrusion 14 and the circumferential groove m are formed by being divided into a root portion of the cylindrical portion 1A and one end portion of the inner ring 3,
The inner ring 3 is in a state where the diameter of the fluid transfer tube 4 made of a flexible material is expanded and press-fitted from the other end of the inner ring 3 to the outer peripheral portion 3G including the large-diameter portion 3b. Is inserted into the cylindrical portion 1A from the one end portion, the circumferential protrusion 14 and the circumferential groove m, which are relatively moved in the direction of the axis P of the cylindrical portion 1A, are press-fitted to fit the seal. Configured to form part S3,
In the forced insertion state, the engaging portion 7 and the engaged portion 13 are moved by moving the union cylinder 2, which is packaged on the cylindrical portion 1 </ b> A, in the circumferential direction after moving in the axial center P direction. Are engaged with each other to form a locked state in which the union cylinder 2 is prevented from moving out in the direction of the axis P.
In the locked state, the diameter-enlarged portion 4 </ b> C of the tube 4 that is fitted on the inner ring 3 interferes with the small-diameter flange portion 12 of the union cylinder 2 in the radial direction, and the axial center of the tube 4. It is characterized in that it can be prevented from coming off in the P direction.

  According to a second aspect of the present invention, in the resin pipe joint according to the first aspect, the engaging portion 7 includes a plurality of projecting portions 7A projecting radially outward from the cylindrical portion 1A, A plurality of vertical recesses 2a formed in the union cylinder 2 are formed to allow relative movement of the plurality of protrusions 7A in the direction of the axis P, and the same circumference is formed from the respective distal ends of the vertical recesses 2a. The engaged portion 13 is constituted by a plurality of lateral concave paths formed in a state extending in the direction.

  According to a third aspect of the present invention, in the resin pipe joint according to the second aspect, the lateral concave path 13 is formed so as to face a circumferential direction in a direction orthogonal to the axis P. It is characterized by.

  According to a fourth aspect of the present invention, in the resin pipe joint according to the second or third aspect, the lateral concave path 13 is formed in a hole penetrating the union cylinder 2 in a radial direction with respect to the axis P. It is characterized by this.

  According to a fifth aspect of the present invention, in the resin pipe joint according to any one of the second to fourth aspects, the union cylinder 2 mounted on the cylindrical portion 1A moves in the axis P direction. The stop mechanism T is configured to stop the protrusion 7A at a position where the projection 7A can move from the vertical concave path 2a to the horizontal concave path 13.

  According to a sixth aspect of the present invention, in the resin pipe joint according to the fifth aspect, the stop mechanism T is a stop protruding from the longitudinal concave path 2a so as to interfere with the protrusion 7A in the direction of the axis P. The wall 2e is formed in the union cylinder 2, and is characterized by the above.

  The invention according to claim 7 is the resin pipe joint according to any one of claims 1 to 6, wherein the union cylinder 2 includes a movable part 18 including the small-diameter flange part 12, and a cylinder main body part 19. On the other hand, it has an elastic support mechanism 20 that elastically supports the movable portion 18 movable in the direction of the axis P to the cylinder main body portion 19, and in the locked state, the movable portion 18 is attached to the enlarged diameter portion 4C. The movable portion 18 and the enlarged diameter portion 4C are configured to be press-contactable in the axis P direction by the restoring elasticity of the elastic support mechanism 20 that is elastically displaced when pushed in the axis P direction. To do.

  The invention according to claim 8 is the resin pipe joint according to any one of claims 1 to 7, wherein the circumferential groove m is in the cylindrical portion 1A and the circumferential protrusion 14 is in the inner ring 3. Inclined outer peripheral surface 5 is formed, and is formed to be tapered at the end in the axial center P direction of the small-diameter cylindrical portion 1a that is formed on the inner side of the circumferential groove m. 11 is formed on the inner side of the circumferential projection 14 in the radial direction of the axis P, and in the forced insertion state, the inclined inner peripheral surface 5 and the inclined outer peripheral surface 11 are A back seal portion S4 formed by being pressed in the direction of the axis P is configured to be formed.

  According to the invention of claim 1, although described in detail in the section of the embodiment, the fitting seal part is constructed by inserting the inner ring with the tube into the cylindrical part, and sufficient sealing performance can be obtained. Since the tube is expanded and forcibly fitted onto the inner ring, the tube and the inner ring are sufficiently sealed. The inner ring with a tube can be kept from coming off by a simple operation of pressing the union cylinder in the axial direction and then rotating it. That is, the resin pipe joint is devised based on the idea that the sealing means is a fitting seal portion and the union cylinder is responsible for preventing the tube from coming off. As a result, it is possible to provide an improved resin pipe joint that is easy to assemble while maintaining the conventional sealing performance, and that can be appropriately installed.

  According to the second aspect of the present invention, the projecting portion that forms the engaging portion is formed in the cylindrical portion, and the lateral concave path that forms the engaged portion is formed in the union cylinder. There exists an advantage which can have the said effect by this invention.

  According to the third aspect of the present invention, since the horizontal concave path is oriented in the circumferential direction in a direction orthogonal to the axis, the projection moves with the horizontal concave path when engaged. The component force to try is not generated. Therefore, there is an advantage that the above-described effect according to the invention of claim 2 can be achieved while the axial center direction can be reliably prevented only by rotating the union cylinder to engage the protrusion and the lateral concave path. .

  According to invention of Claim 4, since the to-be-engaged part is formed as a hole which penetrates a union cylinder, it is sure whether the projection part which makes an engaging part is correctly engaged with the to-be-engaged part. Can be seen from the outside. Therefore, the advantage that the assembly state can be confirmed and inspected easily and conveniently is added, and a resin pipe joint that is further excellent in usability can be provided.

  According to the fifth aspect of the present invention, since the movement of the union cylinder stops in the axial direction at the position where the movement of the protrusion from the vertical concave path to the horizontal concave path is enabled by the function of the stop mechanism, the union cylinder is The locked state can be obtained by a simple and simple operation of inserting in the shape portion and stopping when it is stopped. In other words, if there is no stop mechanism, a trial turning operation of trying to enter the horizontal concave path by moving the union cylinder in the axial direction while moving it in the axial direction is performed a plurality of times (projection and horizontal concave This is because the troublesome trial rotation operation is unnecessary according to the present invention. In this case, as in claim 6, if the stop wall that protrudes into the vertical concave path is formed in the union cylinder, it is possible to easily realize the projecting portion accurately and smoothly to the horizontal concave path using the stop wall as a guide. There are advantages.

  According to the invention of claim 7, although described in detail in the section of another embodiment, there is a slight dimensional error in each part, or the change of the expanded portion of the tube is sudden, and the return movement of the union cylinder returns to the tube. Even when the pressing force is likely to disappear, there is an advantage that the seal part other than the fitting seal part can function reliably while maintaining the advantage that the assembly can be performed by a simple union cylinder operation. In this case, it is advantageous that the seal portion other than the fitting seal portion is a back seal portion arranged inside the fitting seal portion as in the eighth aspect.

Sectional view showing structure of resin pipe joint FIG. 1 is an enlarged sectional view showing the main part of FIG. (A) plan view of union cylinder, (b) front view (A) side view of the union cylinder, (b) cross-sectional view in side view (A) perspective view of union cylinder, (b) perspective view rotated 90 degrees around the axis. (A) Plan view of joint body, (b) Front view (A) side view of joint body, (b) sectional view in side view (A) perspective view of joint body, (b) perspective view rotated 90 degrees around the axis. (A) shows the insertion process, (b) shows the insertion process. The engagement process is shown (a) in the inserted state, (b) in the rotated state. Sectional drawing which shows the state when transfering from an engagement process to a locking process Sectional drawing of the principal part which shows the resin pipe coupling provided with the stop mechanism of another structure The union cylinder used for the resin pipe joint of FIG. 12 is shown, (a) is a perspective view, (b) is a perspective view rotated 90 degrees around the axis. The union cylinder of FIG. 13 is shown, (a) is sectional drawing, (b) is a front view. The other example of a union cylinder is shown, (a) 1st and 2nd separate structure, (b) 3rd separate structure

  Embodiments of a resin pipe joint according to the present invention will be described below with reference to the drawings.

[Example 1]
As shown in FIGS. 1 and 2, the resin pipe joint A (pipe joint structure) includes a joint body 1, a union cylinder 2, and an inner ring 3, and the inner ring 3 is fitted therein. In this state, the tube 4 is connected in communication without leakage. The joint body 1, the union cylinder 2, the inner ring 3, and the tube 4 are all made of a synthetic resin such as a fluororesin (eg, PTFE, PFA, ETFE, CTFE, ECTFE, etc.) having excellent heat resistance and chemical resistance.

  FIG. 1 shows a pipe joint structure in an assembled state in which the tube 4 is attached to the pipe joint A and the union cylinder 2 is properly attached, and the inner peripheral surface 4A of the tube 4 and the inner ring 3 are tapered. The first seal portion S1 formed by contact with the outer peripheral surface 3a, the second seal portion S2 formed by contact between the outer peripheral surface 4B of the tube 4 and the tip of the tubular portion 1A of the joint body 1, and the fitting on the inner ring 3 root side The third seal portion S3 is formed by pressure contact between the combined tube portion 3B and the annular groove m at the base of the cylindrical portion 1A, and the inclined outer peripheral surface 11 that widens the base of the inner ring 3 and the inner diameter side of the cylindrical portion 1A. A fourth seal portion S4 is formed by contact with the inclined inner peripheral surface 5. The third seal portion (an example of a fitting seal portion) S3 that is the main seal portion and the first, second, and fourth seal portions S1, S2, and S4 that are the three sub seal portions are satisfactorily prevented from leaking. A resin pipe joint A to be sealed is formed.

  As shown in FIGS. 1 and 6 to 8, the joint body 1 protrudes toward the other end side with a cylindrical body portion 1 </ b> C, a first tubular portion 1 </ b> A protruding toward one end side in the axis P direction. This is a cylindrical part having a second cylindrical portion 1B, small-diameter cylindrical portions 1a and 1b formed inside the base of each cylindrical portion 1A1B, and an internal flow path 6. Each of the first and second cylindrical portions 1A and 1B and the first and second small diameter cylindrical portions 1a and 1b are the same in opposite directions in the axis P direction. The main body 1 is a symmetric part with respect to the direction of the axis P.

  The detailed structure will be described with one cylindrical portion 1A. The cylindrical portion 1A includes an engaging portion 7 formed at an intermediate portion of the outer periphery in the direction of the axis P, and a tip-expanded inner portion formed at the distal end portion of the inner periphery. It has a peripheral surface 8 and a linear inner peripheral surface 9. The small-diameter cylindrical portion 1 a has a linear outer peripheral surface 10, and a flared inclined inner peripheral surface 5 formed at the tip on the inner diameter side following the internal flow path 6. A straight cylindrical circumferential groove m is formed by the inner peripheral surface 9 of the cylindrical portion 1A and the outer peripheral surface 10 of the small diameter cylindrical portion 1a.

  6-8, the engaging part 7 has two partial flanges (an example of a protrusion part) 7A and 7A, and two local minimum protrusions 7B and 7B, and the axial center from the trunk | drum 1C. This is a part integrally formed with the cylindrical portion 1A in a state of being separated by a distance d in the P direction. The outer peripheral surfaces 7a, 7a of the partial flanges 7A have a predetermined angle range (for example, about 60 degrees) with respect to the axis P (measured in a plane orthogonal to the axis P) with a slightly smaller diameter than the body 1C, and It exists in two places symmetrical about the axis P by 180 degrees. Of the tangential planes related to the outer peripheral surface 1g of the cylindrical portion 1A, the four specific tangent planes 7b intersecting both ends of each outer peripheral surface 7a form the side surfaces of the partial flanges 7A and the both side surfaces of the minimum protrusions 7B. ing. As a result, the engaging portion 7 is symmetric with respect to the axis P and is substantially hexagonal (or viewed in the direction of the axis P) by the pair of outer peripheral surfaces 7a, 7a and the four specific tangent planes 7b. (Outer barrel shape).

  The union cylinder 2 includes a body portion 2A including an engaged portion 13 that can be engaged with the engaging portion 7, and an annular small-diameter flange portion 12 that is formed to project further radially inward at one end side in the axis P direction. In other words, the cross-sectional shape along the direction of the axis P is substantially L-shaped (see FIG. 4A), which is a “cylindrical member having an inward circumferential flange at one end”. The inner diameter of the small-diameter flange 12 is set to be approximately equal to or larger than the outer diameter of the tube 4, and the corner of the engaged portion side end on the inner side of the small-diameter flange 12 is assembling as a pipe joint. It forms in the state used as the press part 12b which bite in order to push the diameter expansion tube part 4A (after-mentioned) to the axial center P direction. The inner peripheral surface 12a of the small-diameter flange portion 12 has a constant diameter, but may be a tapered inner peripheral surface whose diameter gradually increases as the distance from the engaged portion 13 increases in the axis P direction.

  The inside of the trunk portion 2A is formed in a receiving space portion us having the small-diameter flange portion 12 as a depth limit, and the receiving space portion us is a pair of large-diameter inner peripheral surfaces arranged to face each other with respect to the axis P. (An example of a longitudinal concave path) 2a and a pair of small-diameter inner peripheral surfaces 2b opposed to each other with a smaller diameter than the large-diameter inner peripheral surface 2a. The pair of engaged portions 13 is formed in a stepped peripheral hole which is a long hole formed in a thick portion of the body portion 2A having a small-diameter inner peripheral surface 2b on the inner side and extending in the circumferential direction. The stepped peripheral hole 13 includes a single receiving side peripheral surface 13a corresponding to most of the circumferential direction, the introduction side peripheral surfaces 13b and 13b on both sides thereof, the receiving side peripheral surface 13a and each introduction side peripheral surface. It has a pair of stepped surfaces 13c connecting the surface 13b and a single guide side peripheral surface 13d positioned opposite to the axis P direction, that is, 180 degrees axially symmetric. An introduction side peripheral surface 13b is formed corresponding to the stepped inner peripheral surface 2c connecting the large diameter inner peripheral surface 2a and the small diameter inner peripheral surface 2b, and a receiving side peripheral surface 13a is formed corresponding to the small diameter inner peripheral surface 2b. Has been. In addition, the width (width in the direction of the axis P) of the engaged portion 13 at each introduction-side peripheral surface 13b is set to be slightly larger than the thickness of the engaging portion 7 so that the engaging portion 7 can be easily inserted. Has been.

  As shown in FIGS. 1 and 2, the inner ring 3 is a portion into which the tube 4 is press-fitted and fitted, and includes a main body cylinder portion 3A having a large portion of an internal flow path (an example of an inner peripheral portion) 3w, This is a cylindrical synthetic resin part composed of the fitting cylinder portion 3B. The outer peripheral portion 3G into which the tube 4 in the main body cylindrical portion 3A is press-fitted and fitted has a tapered outer peripheral portion (a tapered outer peripheral surface) 3a having a curved shape that protrudes outward in a diameter and having a smaller diameter toward the tip. A large diameter portion 3b which is the largest diameter portion which is tapered in the largest state and continues to the outer peripheral portion 3a, and continues to the large diameter portion 3b in a state where the diameter becomes smaller toward the root (back) in the axis P direction. It is formed with a forward-periphery outer peripheral portion (front-expanded outer peripheral surface) 3c and a straight-body outer peripheral portion (straight-body outer peripheral surface) 3d having a constant diameter following the forward-expanding outer peripheral portion 3c. A cut surface 16 that expands is formed at the tip of the main body cylinder portion 3A. For convenience, the axis of the inner ring 3 is referred to as a cylindrical body axis P.

  The fitting cylinder portion 3B includes an outer circumferential surface 3e fitted into the tubular portion 1A of the joint body 1, an end portion of the outer circumferential surface 3e, and an inner circumferential surface 14a, and a protruding cylindrical portion that can be press-fitted into the circumferential groove m. And a small annular protrusion 15 having an inclined outer peripheral surface 11 located on the inner diameter side of the peripheral protrusion 14. A cut surface 17 is formed at the root end of the annular small protrusion 15 having the internal flow path 3w. The inclined outer peripheral surface 11 and the inner peripheral surface 14a are connected by an annular corner portion (not shown) having a smooth curved surface. The difference in diameter between the straight barrel outer peripheral portion 3d and the outer peripheral surface 3e is such that no gap is formed between the outer peripheral surface 4B of the tube 4 and the inner peripheral surface 9 of the cylindrical portion 1A (or a light press-fit state). So as to be equal to the thickness of the tube 4.

  As shown in FIGS. 1 and 2, in the assembled state, the tube 4 has an enlarged diameter portion 4 </ b> C that is a portion fitted to the outer peripheral portion 3 </ b> G of the inner ring 3 at the end. The diameter-enlarging portion 4C includes a tip tube portion 4d of a straight barrel portion that is fitted on the straight barrel outer peripheral portion 3d, a tip-expanded tube portion 4c that is fitted on the tip-growing outer peripheral portion 3c, and a maximum that is fitted on the large-diameter portion 3b. It consists of a tube portion 4b and a tapered tube portion 4a that is fitted on the tapered outer peripheral portion 3a. Although illustration is omitted, a pretreatment operation for forcibly inserting the end portion of the tube 4 into the outer peripheral portion 3G of the inner ring 3 and press-fitting externally is performed in advance using a press-fitting device. If necessary, the union cylinder 2 may be fitted to the tube 4 before performing this pretreatment operation. The diameter of the internal flow path 4w of the tube 4 is slightly larger than the diameter of the internal flow path 3w of the inner ring 3, but is not limited thereto.

  In order to assemble the resin pipe joint A, the tube 4 on which the inner ring 3 is mounted is inserted into the tubular portion 1A and is inserted, and is inserted into the tube 4 after the insertion step. Alternatively, the union cylinder 2 fitted in advance in the tube 4 is fitted on the cylindrical part 1A with the relative angular position around the axis P so that the engaging part 7 is accommodated in the receiving space part us. A charging process (see FIGS. 9A and 9B) is performed.

  Next, when the union cylinder 2 covered by the cylindrical portion 1A is strongly pressed in the axial center P direction until each guide side peripheral surface 13d passes through the engaging portion 7, this time in the axial center P direction. An engagement process is performed in which each of the partial flanges 7A corresponding to each stepped peripheral hole 13 is taken in and engaged by rotating the union cylinder 2 (rotating operation about the axis P) while maintaining the pressing.

  Then, when the union cylinder 2 is further rotated to adjust the relative angular position around the axis P, the union cylinder 2 is moved back in the direction of the axis P by the stepped surface 13c, and each partial flange 7A corresponds. In a state where the engaging portion 7 is engaged with the engaged portion 13 while being received by the receiving side peripheral surface 13a, the assembly of the resin pipe joint A is completed (see FIG. 1 and 2). For simplicity, the tube 4 is omitted in FIGS.

  In the insertion process, the tube 4 is expanded in diameter so that the inner ring 3 is press-fitted and fitted into the outer peripheral portion 3G including the large-diameter portion 3b from the base end portion (end portion on the main body cylinder portion 3A side) of the inner ring 3. 3 is inserted into the cylindrical portion 1A from the tip portion. As a result, the circumferential protrusion 14 and the circumferential groove m that are relatively moved in the direction of the axis P are forcibly fitted to form the third seal portion S3. Since the third seal portion S3 is structured to enter the circumferential groove m in a press-fitted state in which the circumferential protrusion 14 is compressed inside and outside the diameter, even if the fitting length in the axial center P direction is slightly increased or decreased, Even if the amount of insertion of the inner ring 3 changes somewhat, reliable sealing performance can be obtained.

  The size of the receiving space portion us is a relative angular attitude around the axis P where each partial flange 7A corresponds to each large-diameter inner peripheral surface 2a and each minimal projection 7B corresponds to each small-diameter inner peripheral surface 2b. Is set larger than the engaging portion 7. Therefore, in the fitting step, as shown in FIGS. 9A and 9B, the engagement body 7 and the union cylinder 2 are relatively moved in the direction of the axis P in the relative angle posture, thereby the engagement portion 7. Can be accommodated in the receiving space us.

  As shown in FIG. 11, when the annular distal end surface 2d of the union cylinder 2 is in contact with the side peripheral surface 1c of the trunk portion 1C, the introduction side peripheral surface 13b is in the direction of the axis P and the root side of the partial flange 7A. The stop mechanism T is configured by setting the shape and dimensions to be in the same plane as the wall surface 7c. That is, the stop mechanism T is a position at which the movement of the union cylinder 2 covered by the cylindrical part 1A in the direction of the axis P can be moved from the vertical concave path 2a to the horizontal concave path 13 of the protrusion 7A. More specifically, a stop mechanism T is constituted by the annular tip surface 2d and the side peripheral surface 1c.

  Therefore, in the engaging step, the union cylinder 2 is pushed in the direction of the axis P to bring the annular tip surface 2d into contact with the side peripheral surface 1c of the body 1C, and in this state, it is turned right or left. Thus, the partial flange 7A can be taken into the corresponding stepped peripheral hole 13 and, strictly speaking, the radially inner portion of the stepped peripheral hole 13 (see FIG. 11). When the union cylinder 2 is turned a little, the partial flange 7A is engaged with any one of the introduction-side peripheral surfaces 13b in the direction of the axis P and a temporary stop state (described later) in which a retaining action is generated.

  In the contact state, the pressing portion 12b bites into and pushes the enlarged tube portion 4a. Therefore, when the pushing of the union cylinder 2 is released, the union cylinder 2 is pushed back in the direction of the axis P by the reaction, and moves away. Shows the behavior. Therefore, when the partial flange 7A of the union cylinder 2 is taken into the stepped peripheral hole 13 as much as possible, the root side wall surface 7c is hooked on the introduction side peripheral surface 13b and the retaining action of the union cylinder 2 in the axial center P direction is prevented. Thus, a temporarily fixed state in which the is generated is obtained. FIG. 11 illustrates a cross-sectional view in the temporarily fixed state.

  From there, when the partial flange 7A is positioned at the center (or substantially the center) in the circumferential direction of the stepped peripheral hole 13, the step surface is caused by the reaction force that tends to come off. The partial flange 7A passing through 13c comes into contact with the receiving side peripheral surface 13a and settles, that is, the assembled state shown in FIGS. In this assembled state, the reaction force that acts to escape still acts, but since the step surfaces 13c exist on both sides in the circumferential direction of the partial flange 7a, the union cylinder 2 is also rotated and moved. The locked state in which the sealing function by the third seal portion S3 is maintained is not allowed because the escape movement is not possible.

  That is, the resin pipe joint A according to the present invention moves the engagement portion 7 and the engaged portion 13 by moving in the circumferential direction (in the direction of arrow A in FIG. 11) after moving the union cylinder 2 in the axis P direction. Are engaged to form a locked state in which the union cylinder 2 is prevented from moving out in the direction of the axis P. In the locked state, the third seal portion S3 is formed by fitting the circumferential protrusion 14 and the circumferential groove m, and the small-diameter flange portion 12 of the union cylinder 2 and the tube 4 interfere with each other in the radial direction to cause the inner The ring is configured to be prevented from coming off in the direction of the axis P.

  Moreover, the engaging part 7 is comprised by the partial flange 7A which is the protrusion part of two places (a some example) which protrudes from the cylindrical part 1A to the diameter outer side, and the to-be-engaged part 13 of the some partial flange 7A. A step formed to extend in the same circumferential direction from the respective distal end portions of the large-diameter inner peripheral surface 2a, which is a plurality of vertical concave paths formed in the union cylinder 2 so as to allow relative movement in the axis P direction. A circumferential hole (an example of a horizontal concave path) is provided. The stepped peripheral hole 13 is a peripheral hole whose side peripheral surfaces 13 a, 13 b, and 13 d are flat surfaces orthogonal to the axis P, and is a hole that penetrates the union cylinder 2 in the radial direction with respect to the axis P. It is formed as.

  For example, the engaged portion 13 may be configured as a circumferential groove following the end of the large-diameter inner circumferential surface 2a, that is, an inner circumferential groove having a rectangular cross section that does not penetrate the union cylinder 2 in the radial direction. It is. And if the to-be-engaged part 13 is made into a through-hole like Example 1, it is convenient at the point which can visually confirm whether the partial flange 7A is surely engaged with the stepped peripheral hole 13. FIG. . Further, as the tapered engaged portion 13 provided with a slight angle with respect to the direction orthogonal to the axis P, it is also possible to adopt a configuration in which the union cylinder 2 is further pressed by the turning operation of the union cylinder 2. Is possible.

  In the assembled state shown in FIGS. 1 and 2, the union cylinder 2 moves back in the direction of the axis P by the length of the step surface 13c, but the pressing portion 12b is still in a state of being bitten into the expanded diameter tube portion 4a and pushed. Accordingly, the first seal portion S1, the second seal portion S2, and the fourth seal portion S4 function. Accordingly, in addition to the third seal portion S3, which is sufficient in terms of performance, the sealing function by the other three seal portions S1, S2, S4 is also exhibited, so the union cylinder 2 is pushed in. A resin pipe joint A having sufficient sealing performance can be realized while being simply operated by turning.

  In the assembled state of the resin pipe joint A according to the first embodiment, the pressing portion 12b is tapered to push the tube portion 4a in the direction of the axis P, so that the inner peripheral surface of the tube portion 4a (not shown) And the tapered outer peripheral portion 3a are pressed to form the first seal portion S1. Then, the outer peripheral surface (not shown) of the pre-expanded tube portion 4c and the pre-expanded inner peripheral surface 8 are pressure-contacted to form the second seal portion S2. The circumferential groove m is formed in the cylindrical portion 1A, and the circumferential protrusion 14 is formed in the inner ring 3, and the small-diameter cylindrical portion 1a formed inside the circumferential groove m to form the circumferential groove m. A fourth seal portion (back) by pressure contact in the direction of the axis P between the inclined inner peripheral surface 5 that widens forward and the inclined outer peripheral surface 11 that narrows the annular small protrusion 15 formed inside the peripheral protrusion 14 in the diameter direction. An example of the seal portion) S4 is also formed.

  That is, in the resin pipe joint A according to the first embodiment, the tube 4 is expanded in diameter and is press-fitted and fitted from the other end of the inner ring 3 to the outer peripheral portion 3G including the large-diameter portion 3b. In the forced insertion state in which the inner ring 3 is inserted into the cylindrical portion 1A from one end, the circumferential protrusion 14 and the circumferential groove m that move relative to each other in the direction of the axis P of the cylindrical portion 1A are press-fitted and the fitting seal portion S3. It is comprised so that formation is possible. Then, in the forced insertion state, the engaging portion 7 and the engaged portion 13 are engaged by moving the union cylinder 2 covered by the cylindrical portion 1A in the circumferential direction after moving in the direction of the axis P. Thus, it is configured to be able to form a locked state in which the union cylinder 2 is prevented from moving out in the direction of the axis P. In addition, in the locked state, the enlarged diameter portion 4C and the small diameter flange portion 12 of the union cylinder 2 interfere with each other in the radial direction so that the tube 4 can be prevented from coming off in the axis P direction.

[Example 2]
The resin pipe joint A according to the second embodiment is different in structure of the stop mechanism T from that according to the first embodiment. As shown in FIGS. 12 to 14, the stop mechanism T is configured by forming a stop wall 2 e in the union cylinder 2 that protrudes from the longitudinal concave path 2 a so as to interfere with the protrusion 7 </ b> A in the direction of the axis P. Yes. The structure will be described in detail. The diameter of the inner peripheral surface on the back side in the axial center P direction from the engaged portion 13 in the longitudinal concave path 2a of the union cylinder 2 is reduced (see FIG. 14B), A fitting inner peripheral surface 2f having the same diameter as the peripheral surface 2b is provided, and a pair of stop walls 2e are formed on the side peripheral surface orthogonal to the axis P which is the end surface. The fitting inner peripheral surface 2f is fitted to the outer peripheral surface 1g of the cylindrical portion 1A without rattling.

  Each stop wall 2e and the guide side peripheral surface 13d are formed in a state where the positions in the axis P direction are the same and are the same surface. As a result, when the union cylinder 2 that is externally fitted to the cylindrical portion 1A is moved in the direction of the axis P with the projections 7A corresponding to the vertical recesses 2a entering, the base side of the projection 7A The wall surface 7cg hits the stop wall 2e and cannot be inserted and moved further in the direction of the axis P (see FIG. 12). Then, if the union cylinder 2 is rotated while the root side wall surface 7cg is in contact with the stop wall 2e, the projection 7A is engaged with the stop wall 2e and the guide side peripheral surface 13d (becomes a guide wall). The stop mechanism T acts so as to fit in the joint portion 13.

  Therefore, when assembling the resin pipe joint A of Example 2, the union cylinder 2 is inserted into the cylindrical portion 1A, and if it stops moving in the direction of the axis P, it moves very easily. The above-described locked state can be obtained by an easy operation without the above. The stop mechanism T in the resin pipe joint A according to the first embodiment is a place where the distal end surface 2d of the union cylinder 2 and the side peripheral surface 1c of the body portion 1C are separated from the protrusion 7A and the engaged hole 13 in the axis P direction. In contrast to the means for positioning by contact, the stop mechanism T by the resin pipe joint of the second embodiment is substantially engaged with each other by using the stop wall 2e that is flush with the guide-side peripheral surface 13d. It is means for bringing the projections 7A and the engaged hole 13 into contact with each other. Therefore, compared with the stop mechanism T in the first embodiment, the dimensional accuracy of each component (the cylindrical portion 1A and the union cylinder 2) does not need to be precisely finished (without increasing the cost), and functions well with high accuracy. There is an advantage that the stop mechanism T is provided.

Example 3
As shown in FIG. 12A, the union cylinder 2 includes a movable body 18 including a small-diameter flange 12, a tubular body 19, and a tubular body 19 in a state in which the movable portion 18 is elastically acted in the direction of the axis P. It is convenient to have an elastic support mechanism 20 (first separate structure) to be supported by the robot. With such a configuration, even if the position of the union cylinder 2 in the direction of the axis P is slightly displaced in the escape direction, the movable part 18 always moves the expanded diameter part 4C in the direction of the axis P in the locked state. There is an advantage that the pressure contact state can be brought about by pressing and urging, whereby the first, second, fourth seal portions S1, 2, 4 can be made to function more reliably.

  In the structure depicted on the upper side of the axis P in FIG. 12A, the movable part 18 is fitted to the cylinder body part 19 so as to be relatively movable in the axis P direction. An elastic support mechanism 20 having an elastic urging force that tends to extend in the direction of the axial center P by being restored and expanded by being compressed in the direction of the axial center P such as a coil spring or an annular elastic material is interposed therebetween. For example, the outer peripheral surface 18a of the cylindrical portion 18A of the movable portion 18 and the inner peripheral surface 19a of the proximal end small diameter cylindrical portion 19A of the cylindrical main body portion 19 are fitted, and the outer peripheral surface 18b of the movable portion 18 and the cylindrical main body portion 19 are The small diameter inner peripheral surface 19b is fitted. Reference numeral 22 denotes a snap ring for locking.

  If the union cylinder 2 having such a structure is used, when the union cylinder 2 is strongly pushed in the above-described engagement step, the elastic support mechanism 20 has the axis P due to the contact of the small-diameter flange portion 12 with the enlarged diameter portion 4C. Since it shrinks in the direction, it is possible to reduce the pushing force required to bring the annular tip surface 2d into contact with the side peripheral surface 1c of the body portion 1C, compared with the case where the enlarged diameter portion 4C is excessively compressed in the axis P direction. become. In addition, when the union cylinder 2 slightly moves back in the direction of the axis P when the partial flange 7A comes into contact with the receiving side circumferential surface 13a, the elastic support mechanism 20 expands and moves in this way, and the small diameter flange of the movable portion 18 is moved. The portion 12 reliably presses the enlarged diameter portion 4C in the direction of the axis P.

  As a result, even if there is a slight dimensional error in each part, the elasticity of the tube 4 is not so much or the change in the enlarged diameter portion 4C is abrupt, and the union cylinder 2 returns by the length of the step surface 13c. Even if the pressing force on the tube 4 is likely to disappear due to the movement, the first, second, fourth seal portions S1,2,4 are surely maintained while maintaining the advantage of being able to be assembled by simple union cylinder operation. An additional effect that it is possible to obtain a functioning state can also be achieved.

  The structure depicted on the lower side on the paper surface of the axis P in FIG. 12A is a structure in which the cylindrical portion 18A is fitted onto the thin inward flange 21 of the union cylinder 2 (second separate structure). The functions and effects are the same as those of the structure described above.

  The structure shown in FIG. 12B is a modification of the union cylinder 2 having the structure shown in FIG. 12, and the elastic support mechanism 20 is omitted by omitting the radially inner fitting structure between the movable part 18 and the cylinder body part 19. Is exposed to the inside of the diameter (third separate structure). Also in this example, the functions and effects are the same as those of the above-described structure shown in FIG.

[Other alternative embodiments]
The cylindrical portion 1A can also be defined as a portion that integrally protrudes from a fluid device such as a pump or a valve (a cylindrical portion 1A made of synthetic resin provided in the fluid device 1).

1 Fitting body (fluid equipment)
DESCRIPTION OF SYMBOLS 1A Cylindrical part 1a Small diameter cylindrical part 2 Union cylinder 2a Longitudinal concave 2e Stop wall 3 Inner ring 3b Large diameter part 3G Outer part 4 Tube 4C Expanded part 5 Inclined inner peripheral surface 7 Engaging part 7A Protrusion part 11 Inclined outer peripheral surface 12 Small-diameter collar 13 Engaged part (horizontal concave)
14 circumferential projection 15 annular small projection portion 18 movable portion 19 cylinder body portion 20 elastic support mechanism P shaft center S3 fitting seal portion S4 back seal portion T stop mechanism m circumferential groove

Claims (8)

A synthetic resin cylindrical portion provided on the joint body or fluid device having an engagement portion, a synthetic resin inner ring having a large-diameter portion protruding outward in the outer diameter, and the engagement portion A synthetic resin union cylinder having an engageable part that can be engaged and externally mounted on the cylindrical part;
A circumferential protrusion and a circumferential groove are formed by being distributed between a root portion of the cylindrical portion and one end portion of the inner ring,
The inner ring in a state where a diameter of a fluid transfer tube made of a flexible material is expanded and press-fitted from the other end portion of the inner ring to the outer peripheral portion including the large-diameter portion from the one end portion. In the forced insertion state inserted into the cylindrical portion, the circumferential protrusion and the circumferential groove that move relative to each other in the axial direction of the tubular portion are press-fitted and configured to form a fitting seal portion,
In the forced insertion state, the engagement portion and the engaged portion are engaged with each other by moving the union tube that is externally mounted on the cylindrical portion in the axial direction and then moving in the circumferential direction. The union cylinder is configured to be able to form a locked state in which the unmoving movement in the axial direction is prevented,
In the locked state, the diameter-enlarged portion of the tube that is externally fitted to the inner ring interferes with the small-diameter flange portion of the union cylinder in the radial direction, and the tube is prevented from coming off in the axial direction. Resin pipe fittings that can be configured.   The engaging portion is composed of a plurality of protrusions projecting radially outward from the cylindrical portion, and a plurality of protrusions on the union cylinder to allow relative movement of the plurality of protrusions in the axial direction. 2. The resin according to claim 1, wherein the engaged portion is configured by a plurality of horizontal concave paths that are formed in a state in which the vertical concave paths are formed and extend in the same circumferential direction from the distal ends of the vertical concave paths. Pipe fittings.   The resin pipe joint according to claim 2, wherein the lateral concave path is formed so as to face a circumferential direction in a direction orthogonal to the axis.   The resin pipe joint according to claim 2 or 3, wherein the lateral concave path is formed in a hole penetrating the union cylinder in a radial direction with respect to the axis.   A stop mechanism is configured to stop the movement of the union cylinder in the axial direction of the union cylinder at the position where the protrusion can move from the vertical concave path to the horizontal concave path. The resin pipe joint according to any one of claims 2 to 4.   The resin pipe joint according to claim 5, wherein the stop mechanism is formed by forming a stop wall in the union cylinder so as to protrude from the vertical concave path so as to interfere with the protrusion in the axial direction. .   The union cylinder has a movable part including the small-diameter flange part, and an elastic support mechanism that elastically supports the movable part movable in the axis P direction with respect to the cylinder main body part on the cylinder main body part, In the locked state, the movable part and the enlarged-diameter part can be pressed in the axial direction by the restoring elasticity of the elastic support mechanism that is elastically displaced by being pushed by the enlarged-diameter part in the axial direction. The resin pipe joint according to any one of claims 1 to 6, which is configured as follows.   The circumferential groove is formed in the cylindrical portion, and the circumferential protrusion is formed in the inner ring, and the inside of the small diameter cylindrical portion, which is the inner diameter of the circumferential groove, expands toward the end in the axial direction. An annular small protrusion having an inclined outer peripheral surface that is tapered at the end in the axial direction is formed on a radially inner side of the peripheral protrusion, and in the forced insertion state, The resin pipe joint according to any one of claims 1 to 7, wherein a deep seal portion is formed by pressing a peripheral surface and the inclined outer peripheral surface in the axial direction.

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