JP2005344796A - Fluid equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To economically arrange a mechanism capable of being adjusted for the flow and the pressure of an orifice, etc., without increasing the costs and installation space by taking note of fluid equipment having a pipe joint structure. <P>SOLUTION: In a valve having the pipe joint structure, there is comprised of a joint part 1 having an annular portion 6 with a male screw 9, an inner ring 4 having a swelling part 11a swelling out toward the outside diameter side, and a union nut 2 having a female screw 18 engageably with the male screw 9. In the state where the end of a flexible tube 3 is fitted between the outer peripheral surface of the inner ring 4 and the inner peripheral part of the annular portion 6, a sealing part S is formed to make the interval between the swelling part 11a and the inner peripheral part of the tube 3, and the interval between the outer peripheral part of the tube 3 and the inner peripheral part of the annular portion 6 come closely into contact to be fastened by screwing the union nut 2 into the root side of the annular portion 6. A fluid transfer passage 4W of the inner ring 4 for fluid transfer has an orifice passage 20 in which the cross sectional area is smaller than that of a fluid transfer passage 1W of the joint part 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fluid device having a pipe joint structure, and more specifically, a valve (stop valve, flow rate control valve, etc.), pump (metering pump, slurry pump, etc.), joint, accumulator, flow meter, tank, filter, etc. The present invention relates to a fluid device having a pipe joint structure used for pipe connection of various fluid devices.

  Conventionally, in order to adjust the flow rate and pressure in a fluid piping system or the like, it is well known to provide a flow rate control valve or a pressure control valve. However, this means is over-spec, and the cost is inevitably increased. For this reason, in general, an orifice is provided somewhere in the flow path to provide a means for adjusting the flow rate and pressure. In this case, it is designed to partially narrow the flow path of a fluid device such as a pump or an on-off valve, or to separately install components that narrow the flow path such as an orifice in the middle of the piping system.

  As an example of the latter technique (installing parts that narrow the flow path of the piping system separately), those disclosed in Patent Documents 1 and 2 are known. That is, Patent Document 1 discloses a structure in which an orifice is welded and attached in a tube having a joint structure at both ends. In Patent Document 2, a connecting cylinder member for connecting pipes to a pipe is disclosed. A structure in which a ring-shaped plate body in which a throttle hole is formed is provided is disclosed. In any of these means, a separate member (part) dedicated for forming an orifice is additionally set.

  However, the former technique (designing to partially narrow the flow path of the device) requires a special design inside to form an orifice in the fluid device or piping, and is dedicated. In addition, when various orifices are set, the number of types of devices increases by the set number, which is not realistic because it leads to an increase in the number of parts and an increase in management costs. In the latter technique, the cost increases due to the additional installation of the parts forming the orifice, and a space for adding the parts is also required, which hinders the downsizing of the apparatus. In addition, since the number of seals increases due to the addition of parts, it is not a good means in terms of fluid leakage and stagnation. Therefore, there is still room for improvement in any means.

On the other hand, as a joint structure used in piping systems using fluid equipment and tubes in recent years, it is possible to eliminate leakage from the pipe connection part almost completely by tightening and fixing with a union nut using an inner ring. Means are known. As such a joint structure, there is one disclosed in Patent Document 3. Today, the joint structure using the inner ring is widely used as a technical standard in the fluid piping system, and this joint structure is present in most piping systems.
JP 2003-194283 A Japanese Patent Laid-Open No. 10-301633 JP 2000-283372 A

  Accordingly, an object of the present invention is to provide a mechanism capable of adjusting the flow rate and pressure of an orifice or the like by focusing on a fluid structure having a joint structure using an inner ring frequently used in a fluid piping system, in particular, a pipe joint structure such as a pump. Is to be economically deployed without increasing costs or increasing installation space.

According to the first aspect of the present invention, there is provided a sealing inner member having a tubular portion 6 projecting from the device main body 1 with a male screw portion 9 formed on the outer periphery, and an annular large-diameter portion 11a raised on the outer diameter side. It comprises a ring 4 and a union nut 2 in which a female screw part 18 that can be screwed to the male screw part 9 is formed.
The tubular portion of the union nut 2 in a state where the end of the fluid transfer tube 3 made of a flexible material is fitted between the outer peripheral surface 4G of the inner ring 4 and the inner peripheral portion of the tubular portion 6. 6 is tightened by screwing to the root side, between the annular large diameter portion 11a of the inner ring 4 and the inner peripheral portion of the tube 3, and the outer peripheral portion of the tube 3 and the inner peripheral portion of the tubular portion 6. In the fluid device having a pipe joint structure in which the seal portion S that closely contacts at least one of the
The fluid transfer flow path 4W of the inner ring 4 has an orifice flow path 20 whose cross-sectional area is smaller than the cross-sectional area of the fluid transfer path 1W of the device main body 1.

  According to a second aspect of the present invention, in the fluid device having the pipe joint structure according to the first aspect, the seal portion S is disposed on the inner peripheral portion of the distal end portion of the tubular portion 6 with respect to the axis C of the tubular portion 6. The end portion of the tube 3 is inclined between a seal surface 8 constituted by a tapered surface intersecting with each other and an inwardly tapered surface 15 formed on the inclined surface portion of the annular large diameter portion 11a of the inner ring 4. It is characterized by being sandwiched between states.

  According to a third aspect of the present invention, in the fluid device having the pipe joint structure according to the first or second aspect, the fluid passage 4W has an orifice passage 20 that is open at one end of the inner ring 4. The transfer path 21 having a larger cross-sectional area than this and opening to the other end of the inner ring 4, and the orifice flow path 20 and the transfer path 21 in a state where the cross-sectional area gradually changes in the fluid transfer direction. It is characterized by comprising a taper flow path 23 connected in communication.

  According to a fourth aspect of the present invention, in the fluid device having the pipe joint structure according to the first or second aspect, the fluid transfer flow path 4W has a larger cross-sectional area than the orifice flow path 20. The first and second transfer passages 21 and 22 formed on both sides of the orifice passage 20 and the first transfer passage 21 and the orifice passage 20 open to one end of the inner ring 4. A first taper flow path 23 that communicates with each other in a state in which a cross-sectional area gradually changes in the fluid transfer direction, and the second transfer path 22 and the orifice flow path 20 that are open to the other end of the inner ring 4. The second taper flow path 24 is formed, in which the cross-sectional area is connected in a state where the cross-sectional area gradually changes in the fluid transfer direction.

  The configuration of claim 5 is the fluid device having the pipe joint structure according to any one of claims 1 to 4, wherein the end on the root side of the inner ring 4 is closer to the root than the annular large diameter portion 11 a. The tubular portion 6 or the device main body 1 is fitted inside, and the tubular portion 6 or the device main body 1 and the inner ring 4 at the inner fitting portion are connected to the root side of the tubular portion 6 of the union nut 2. A back seal portion Q that is in close contact with each other by tightening by screwing is formed.

  According to a sixth aspect of the present invention, in the fluid device having the pipe joint structure according to the fifth aspect, the back seal portion Q gradually expands outward in the axis C direction of the tubular portion 6 or the device main body 1. It is characterized in that it is formed by close contact between a sealing surface 7 constituted by a taper surface having a diameter and a projecting end surface 12 comprising a taper surface formed at an end of the inner ring 4.

  According to a seventh aspect of the present invention, in the fluid device having the pipe joint structure according to the sixth aspect, the back seal portion Q is more radially outward than the seal surface 27 of the tubular portion 6 or the device main body 1. The cylindrical portion 26 formed at the end of the inner ring 4 is fitted into an annular groove portion 28 formed in parallel with the axis C of the tubular portion 6.

  According to the configuration of claim 1, the inner diameter of the inner ring, which is an indispensable component for configuring the pipe joint structure, that is, the flow path for fluid transfer is throttled, and the orifice flow path having the required size (cross-sectional area). The flow rate and pressure can be adjusted without adding new dedicated parts, increasing the number of parts, or changing the piping system. In other words, since the inner ring can have both functions of being a component of a pipe joint and being an orifice, the conventional pipe joint structure can be used so as not to increase the cost. However, it is possible to provide a fluid device having a rational pipe joint structure capable of adjusting the flow rate and pressure of the fluid. And since the fluid apparatus which has such a pipe joint structure exists in many places throughout a piping system, there exists an advantage which has a high freedom degree of design and can be remodeled easily.

  According to the configuration of claim 2, the seal portion is configured by sandwiching the tube end portion in an inclined state between the tapered surface of the distal end of the tubular portion and the inwardly tapered surface of the inner ring. A fluid device having a pipe joint structure capable of providing a reliable sealing function while having the above-described effect of the configuration can be provided.

  According to the configuration of the third aspect, the fluid transfer path of the joint body or the flow path of the tube and the orifice flow path are connected by the tapered flow path so that the cross-sectional area gradually changes. The flow of fluid through the front and back can be smoothed, and pressure loss and fluid stagnation can be reduced.

  According to the fourth aspect of the present invention, the fluid flow path of the joint body, the flow path of the tube, and the orifice flow path are connected by the tapered flow path so that the cross-sectional area gradually changes. The flow of fluid through the ring and the front and rear thereof can be smoothed, and pressure loss and fluid stagnation can be reduced. That is, the effect of the configuration of claim 3 is exerted on both sides of the orifice flow path, and there is an advantage that the effect of reducing pressure loss and fluid stagnation is enhanced regardless of the flow direction of the fluid. is there.

  According to the structure of Claims 5-7, since the back seal part by the edge part by the side side of an inner ring and a tubular part or a coupling main body is attached, there exists the said effect by the structure of Claim 3 or 4. However, there is an advantage that the sealing function is further strengthened.

  Hereinafter, a fluid device having a pipe joint structure according to the present invention will be described with reference to the drawings. 1 is a cross-sectional view showing the structure of a manual stop valve that is an example of a fluid device, FIG. 2 is an enlarged cross-sectional view showing the structure of the pipe joint, and FIGS. 3 to 5 are cross-sectional views showing other structures of the inner ring. It is. FIG. 6 is an enlarged cross-sectional view showing another structure of the pipe joint portion, and FIG. 7 is an overall perspective view showing an accumulator which is another example of the fluid device.

  A manual stop valve as a fluid device according to the first embodiment and the structure of a pipe joint portion thereof, that is, a pipe joint structure are shown in FIGS. 1 and 2, respectively. As shown in FIG. 1, the stop valve R is composed of a valve body 31 and a pair of pipe joint portions A and A provided on both sides thereof. The pipe joint portion A includes a joint portion 1 formed integrally with the valve body 31 in a concentric state with the axis C of the internal fluid transfer path 1W, an union nut 2 that can be externally fitted and screwed to the joint portion 1, and a joint Each of the inner and outer inner rings 4 and 54 can be fitted into the portion 1 freely.

  The valve body 31 is formed of a resin having excellent chemical resistance and heat resistance, such as PTFE, PFA, ETFE, CTFE, and ECTFE. A shaft-like valve body 35 is fitted and supported on the center rising portion 31B in the direction of the axis C via an outer ring 33 and a pusher ring 34 so as to be able to be lifted and lowered, and a lift shaft is attached to an upper end portion of the shaft-like valve body 35. A manual stop valve R is configured by fixing an opening / closing operation knob 36 through 37.

  As shown in FIG. 2, the pipe joint portion A includes a union nut 2 and inner rings 4, 54 formed of a resin such as a fluororesin (eg, PTFE) each having excellent heat resistance and chemical resistance, and a joint portion 1. The inner rings 4 and 54 are made of a resin tube such as a fluororesin (for example, PTFE) that is inserted into and connected to the joint portion 1 of the stop valve R (a tube for fluid transfer made of a flexible material). Example) is press-fitted into one end 3a of 3.

  The joint portion 1 is formed with a receiving port (an example of a tubular portion) 6 at least at one end portion of the cylindrical body portion 5, and a first primary portion constituting a back seal portion Q at the inner back of the receiving port 6. A seal portion (an example of a seal surface) 7 is formed so as to intersect the axis C of the joint portion 1, and a secondary seal portion (an example of the seal surface and the seal portion S) 8 is provided at the inlet of the receiving port 6. It is formed so as to intersect C. A male screw portion 9 is formed on the outer periphery of the receiving port 6. The inner diameter of the receiving port 6 is formed to be larger than the inner diameter of the trunk portion 5, and the inner diameter of the receiving port 6 is gradually reduced in the axial direction toward the inner diameter surface of the trunk portion 5. The primary seal portion 7 is formed by the tapered surface. On the other hand, the secondary seal portion 8 is formed by a tapered surface that gradually increases in diameter from the inner depth of the receiving port 6 toward the outer side in the axial direction and reaches the end surface of the receiving port 6.

  The inner rings 4 and 54 are resin molded products such as fluororesin (for example, PTFE), and an outer diameter protruding portion 10 that can be fitted into the receiving port 6 of the joint portion 1 is formed at an inner end portion in the axial direction. At the same time, a press-fit portion 11 that is press-fitted into the one end portion 3a of the tube 3 is formed at the outer end portion in the axial direction, and has a sleeve shape as a whole. On the inner end surface of the projecting portion 10, an inner end seal portion (an example of a projecting end surface) 12 made of a tapered surface that abuts on the first primary seal portion 7 is formed. The press-fitting portion 11 includes a bulging portion (an example of an annular large-diameter portion) 11 a and a connecting portion 11 b that connects the bulging portion 11 a and the protruding portion 10. The outer diameter of the connecting portion 11 b is the outer diameter of the protruding portion 10. It is set to be thinner than the thickness of the tube 3. The bulging portion 11a includes a tapered outer end seal portion 13 that gradually increases in diameter from the axial outer end toward the axial inner end side, and a connecting portion from the top of the outer end seal portion (an example of the seal portion S) 13 It is formed in a cross-sectional mountain shape having a tapered surface (an example of an inwardly tapered surface) 15 that gradually decreases in diameter toward 11b.

  The outer diameter of the top portion of the outer end seal portion 13, that is, the maximum outer diameter of the bulging portion 11a is set larger than the outer diameter of the connecting portion 11b. The taper surface 15 has an inclination angle that substantially coincides with the inclination angle of the secondary seal portion 8 of the joint portion 1, and when the inner end seal portion 12 contacts the primary seal portion 7, the secondary seal portion 8. And the taper surface 15 are formed so that the distance between them faces the thickness of the tube 3. In addition, although mentioned later in detail, the inner diameter d4 of the inner ring 4 on the outer side is clearly smaller than the inner diameter d3 of the tube 3 and the inner diameter d1 of the body portion 5 of the joint portion 1 to adjust the flow rate and pressure. It is configured to function as an orifice.

  These inner rings 4, 54 are press-fitted into the one end 3 a of the tube 3 with the protruding portion 10 protruding outward, thereby expanding the diameter of the one end 3 a of the tube 3 to form the expanded portion 16. At the same time, the enlarged diameter root portion 17 is provided where the inclined surface portion 16a opposite to the insertion direction of the enlarged diameter portion 16 into the joint portion 1 and the outer surface portion 30 of the tube parallel to the tube axial direction meet. Form.

  In a state where the one end portion 3 a of the tube 3 is inserted into the receiving port 6, the inner end seal portion 12 contacts the first primary seal portion 7 of the joint portion 1, and the outer end seal portion 13 expands the tube 3. It abuts against the inner surface of the anti-insertion direction side inclined surface portion 16a which becomes the second primary seal portion of the diameter portion 17. Furthermore, the one end portion 3a of the tube 3 is sandwiched between the secondary seal portion 8 of the joint portion 1 and the tapered surface 15 of the inner rings 4 and 54 in an inclined state. That is, the insertion direction side inclined surface portion 16 b of the expanded diameter portion 16 of the tube 3 deformed along the tapered surface 15 of the inner rings 4, 54 contacts the secondary seal portion 8.

  The union nut 2 is formed with a female screw portion 18 to be screwed to the male screw portion 9 of the joint portion 1 on the inner periphery of the union nut 2, and an annular flange portion 19 projects inwardly at one end portion. An acute-angle or right-angle pressing edge portion 19 a is formed at the axially inner end of the inner peripheral portion of the flange portion 19.

  The union nut 2 is loosely fitted in advance to the outer periphery of the one end portion 3a in a state where the one end portion 3a of the tube 3 into which the inner rings 4 and 54 are press-fitted is inserted into the receiving port 6 of the joint portion 1. The female screw portion 18 is screwed into the male screw portion 9 of the joint portion 1 and tightened. Along with this tightening, the pressing edge portion 19a of the union nut 2 abuts against the enlarged diameter root portion 17 of the enlarged diameter portion 16 of the tube 3 and presses the inner rings 4, 54 from the axial direction, whereby the inner rings 4, 54 are pressed. The inner end seal portion 12 and the slope portion 16b on the insertion direction side of the tube 3 are pressed against the primary seal portion 7 and the secondary seal portion 8 of the receiving port 6 of the joint portion 1, respectively, and the second 1 The inner surface of the slope 16a on the side opposite to the insertion direction, which is the next seal portion, is pressed against the outer end seal portion 13 of the inner rings 4 and 54 to provide a sealing property (sealing force), and at the same time, the tube 3 is prevented from being removed. ing.

  As shown in FIGS. 1 and 2, the inner ring 4 on the outer side has a cross-sectional area of the fluid transfer channel 4 </ b> W formed as an inner peripheral portion thereof, which is larger than the cross-sectional area of the fluid transfer path 1 </ b> W of the joint portion 1. A small orifice channel 20 is provided. Specifically, the orifice channel 20 is made by setting the diameter d4 of the fluid transfer channel 4W having a circular cross section to be smaller than the diameter d1 of the fluid transfer channel 1W having the same circular cross section. . The inner diameter d3 of the tube 3 is the same as the diameter d1 of the fluid transfer path 1W, and the inner ring 4 functions as an orifice for both the joint portion 1 and the tube 3. The inner diameter of the fluid transfer channel 54W of the inner ring 54 on the in side is set to be the same as the diameter d1 of the fluid transfer channel 1W and the inner diameter d3 of the tube 3.

  The fluid equipment having such a pipe joint portion A includes, in addition to the stop valve R, pumps, joints, accumulators, flow meters, tanks, filters, etc., all of which are present throughout the piping system. Therefore, the orifice 20 can be freely provided in these fluid devices. Therefore, by using the fluid device having the pipe joint structure according to the present invention, the fluid can be produced in a rational and economical state without causing an increase in the number of parts and an increase in cost and with a high degree of design freedom. Flow rate and pressure can be adjusted.

  The connection method of the tube 3 in the pipe joint part A of the stop valve R is as follows. First, the first step of fitting and inserting the union nut 2 through the tube 3 is performed. Next, the 2nd process of inserting and fitting the end part of tube 3 in bulging part 11a and connecting part 11b in inner rings 4 and 54 is performed. In this second step, the inner ring 4 on the outer side has an orifice channel 20 in which the cross-sectional area of the fluid transfer channel 4W is smaller than the cross-sectional area of the fluid transfer channel 1W of the joint portion 1. Is used. Further, if the tube 3 is short and the other end is in an open state, the first step may be performed after the completion of the second step.

  And the 3rd process of fitting the inner rings 4 and 54 by which the edge part of the tube 3 was fitted in the receptacle 6 projected from the joint part 1 in the state by which the external thread part 9 was formed in the outer periphery is carried out. Do. Finally, the union nut 2 fitted in the tube 3 is screwed into the receiving port 6 and is tightened by screwing the receiving port 6 toward the root side, thereby to Connecting the tube 3 to the pipe joint A by performing the fourth step of sealing both the inner periphery of the tube 3 and the outer periphery of the tube 3 and the inner periphery of the receiving port 6 Is completed.

  By the way, the inner ring 4, 54 used in the pipe joint portion A of the stop valve R shown in FIGS. 1 and 2 includes an outer peripheral portion 4G having a bulging portion 11a raised on the outer diameter side, and a fluid transfer channel 4W, The inner peripheral portion 4N and the outer peripheral portion 4G of the receiving port 6 projecting from the joint portion 1 in a state in which the male screw portion 9 is formed on the outer periphery. The receiving port 6 of the union nut 2 in which a female screw part 18 that can be screwed to the male screw part 9 is formed in a state in which the end of the fluid transfer tube 3 made of a flexible material is fitted between the male screw part 9 and the male screw part 9. Between the bulging portion 11a and the inner peripheral portion 3N of the tube 3 and between the outer peripheral portion 3G of the tube 3 and the inner peripheral portion 6N of the receiving port 6 It is an inner ring in which seal portions 8 and 13 are attached to at least one of them. , Fluid transfer passage 4W out side is characterized in that the cross-sectional area of which has an orifice passage 20 to be smaller than the cross-sectional area of the fluid flow path 1W coupling element 1.

  The inner rings 4 and 54 are tightened by screwing the union nut 2 into the root side of the receiving port 6 so that the receiving port 6 or the joint portion 1 and the end portion on the root side of the main body cylinder 4H are in close contact with each other. An end on the base side of the bulging portion 11a in the main body cylinder 4H is formed so as to be fitted in the receiving port 6 or the joint portion 1 so that a primary seal portion (an example of a back seal portion) 7 is configured. ing.

  As shown in FIG. 1 and the like, the outer-side inner ring 4 has a fluid transfer flow path 4W composed of only a single-diameter orifice flow path 20 as well as the shape shown in FIGS. It may have a fluid transfer channel 4W. That is, the inner ring 4 for the pipe joint having the first and second different structures shown in FIGS. 3 and 4 is separated from the orifice channel 20 in which the fluid transfer channel 4W is open at one end. The transfer path 21 has a large area and is open at the other end, and the tapered flow path 23 that connects the orifice flow path 20 and the transfer path 21 in a state where the cross-sectional area gradually changes in the fluid transfer direction. It is a thing.

  The inner ring 4 having the first different structure shown in FIG. 3 has an orifice channel 20 formed at the tube side end and a transfer path 21 formed at the joint body side end. The ring 4 has the reverse configuration. The inner ring 4 having the first different structure is suitable for a structure in which fluid flows from the joint portion 1 toward the tube 3, and the inner ring 4 having the second different structure flows in the fluid from the tube 3 toward the joint portion 1. Suitable for structure.

  Further, the inner ring 4 having the third different structure shown in FIG. 5 is formed on both sides of the orifice channel 20 with the fluid transfer channel 4W having a larger sectional area than the orifice channel 20. The first and second transfer paths 21 and 22 are connected to each other and communicated with the first transfer path 21 opened at one end and the orifice channel 20 in a state where the cross-sectional area gradually changes in the fluid transfer direction. 1 taper flow path 23 and a second taper flow path 24 that connects the second transfer path 22 open to the other end and the orifice flow path 20 in a state where the cross-sectional area gradually changes in the fluid transfer direction are formed. ing.

  In the inner ring 4 having the first and second different structures, the corner portion 1s (see FIGS. 2 and 6) of the transfer path 1W of the joint portion 1 where the orifice channel 20 faces, or the corner angle of the transfer path 3W of the tube 3 is used. There is a possibility that the fluid stagnates and stagnates in the portion 3s (see FIGS. 2 and 6), but in the inner ring 4 of this third separate structure, the taper channels 23 and 24 exist in either direction. While providing the orifice channel 20 for narrowing the channel, there is an advantage that the fluid can flow smoothly without stagnation.

  The fluid device according to the second embodiment is a stop valve that is different only in the structure of the pipe joint portion A of the stop valve according to the first embodiment, and only the pipe joint portion A2 will be described below. The pipe joint portion A2 according to the second embodiment is the same as the pipe joint A according to the first embodiment shown in FIG. 1 except that the back seal portion Q and the structures on the outside thereof are different, and the same members and elements are the same. The description is omitted. That is, as shown in FIG. 6, the primary seal portion 7 having a different structure is formed in the projecting portion 10 projecting from the one end portion 3 a of the tube 3 of the inner ring 4, inside the receiving port 6 of the joint portion 1. A cylindrical seal portion (an example of a cylindrical portion) 26 that protrudes radially outward and inward in the axial direction from the protruding inner end surface 25 that contacts the sealing surface 27 that is a tapered surface is formed.

  On the other hand, a cylindrical groove portion (annular groove portion) that forms a seal portion by generating a surface pressure in the radial direction along with the press-fitting of the cylindrical seal portion 26 on the radially outer side than the seal surface 27 of the receiving port 6 of the joint portion 1. Example) 28 is formed. The primary seal portion 7 is formed by a tapered surface that gradually decreases in diameter toward the inner side in the axial direction. In the case of this pipe joint A2, only the outer peripheral surface of the cylindrical seal portion 26 can be brought into close contact with the cylindrical groove portion 28 to constitute the seal portion.

  Further, at the base of the receiving port 6, a receiving wheel 51 that is prevented from coming off by a ring protrusion 1 t formed at the base is fitted and mounted, and an opposing wheel 52 that can freely come into contact with the receiving wheel 51. Are attached to the end face of the union nut 2, and the receiving wheel 51 and the counter wheel 52 constitute a moderation mechanism 50 that defines the tightening limit position of the union nut 2. The fluid transfer flow path 4W of the inner ring 4 used for the pipe joint A2 is depicted as a single-diameter orifice flow path 20 as in the pipe joint A according to the first embodiment. Thus, the inner ring 4 can be replaced with another structure shown in FIGS.

  The fluid device according to the third embodiment is an accumulator R shown in FIG. The accumulator R has an accumulator main body 40 including a cylindrical casing 41 whose upper end is closed and a bottom wall 42 which closes an open lower end of the casing 41 in an airtight manner. The flange portion 43 and the flange portion 44 on the bottom wall 42 side are tightened and integrated using a plurality of bolts 45.

  Also in this accumulator R, the pipe joint part A for connecting the tube 3 exists on both sides of the bottom wall 42, and the pipe joint structure is as previously disclosed in FIG. Therefore, the above-described orifice channel 20 can be provided also in the inner ring 4 used in the pipe joint portion A of the accumulator R, and the flow rate and pressure of the fluid are adjusted at the fluid inlet and outlet to the accumulator R. be able to.

  In the inner ring 4 used in the various fluid devices R described above, the sectional area (diameter) of the orifice channel 20 can be changed and set as necessary. The degree of change (change in cross-sectional area with respect to the channel length) can be set as appropriate. Moreover, the joint part 1, the union nut 2, and the inner ring 4 can also be formed with things other than a fluororesin. It is also possible to provide the orifice channel 20 only in the inner ring 54 on the in side, or provide the orifice channel 20 in the inner rings 4 and 54 on both the out side.

Cross section of valve with pipe joint Sectional drawing (Example 1) which shows the pipe joint structure of the out side in the valve | bulb of FIG. Sectional view showing the first alternative structure of the inner ring Sectional view showing the second alternative structure of the inner ring Sectional view showing the third separate structure of the inner ring Sectional drawing which shows pipe joint structure in fluid equipment (Example 2) Overall perspective view of accumulator with pipe joint

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Joint part 1W Fluid transfer path 2 Union nut 3 Fluid transfer tube 4,54 Inner ring 4G Outer peripheral part 4H Main body cylinder 4N Inner peripheral part 4W, 54W Fluid transfer flow path 6 Tubular part 7,27 Seal surface 8 Seal surface 9 Male thread part 11a Annular large-diameter part 12 Projection end face 15 Inwardly tapered surface 18 Female thread part 20 Orifice channel 21, 22 Transfer path (first and second transfer paths)
23, 24 Tapered channel (first and second tapered channels)
26 Cylindrical part 28 Annular groove part A Pipe joint part C Axis of tubular part Q Back seal part R Fluid equipment S Seal part

Claims (7)

A tubular part projecting from the device body with a male screw part formed on the outer periphery, an inner ring for sealing having an annular large-diameter part raised on the outer diameter side, and screwable to the male screw part Consisting of a union nut with a female thread
To the root side of the tubular portion of the union nut in a state where an end portion of a fluid transfer tube made of a flexible material is fitted between the outer peripheral surface of the inner ring and the inner peripheral portion of the tubular portion. By tightening by screwing, at least one of the annular large-diameter portion of the inner ring and the inner peripheral portion of the tube and the outer peripheral portion of the tube and the inner peripheral portion of the tubular portion are in close contact with each other. A fluid device having a pipe joint structure in which a sealing portion is configured,
The fluid transfer channel of the inner ring is a fluid device having a pipe joint structure having an orifice channel whose cross-sectional area is smaller than the cross-sectional area of the fluid transfer channel of the device main body.   The seal portion is formed on the inner peripheral portion of the distal end portion of the tubular portion, on the seal surface formed by a tapered surface intersecting the axis of the tubular portion, and on the slope portion of the annular large diameter portion of the inner ring. The fluid apparatus which has the pipe joint structure of Claim 1 comprised by clamping the edge part of the said tube in an inclined state between the formed inward taper surfaces.   The orifice flow path in a state where the fluid transfer flow path opens at one end of the inner ring, the transfer path in a state where the cross-sectional area is larger than that and opens at the other end of the inner ring, and the orifice flow The fluid device having a pipe joint structure according to claim 1 or 2, comprising a tapered flow path that connects the path and the transfer path in a state where a cross-sectional area gradually changes in the fluid transfer direction.   The fluid transfer flow path includes the orifice flow path and first and second transfer paths formed on both sides of the orifice flow path in a state where the cross-sectional area is larger than the orifice flow path, and the inner ring. A first taper channel that connects the first transfer channel and the orifice channel in a state of opening to one end of the inner ring in a state where a cross-sectional area gradually changes in the fluid transfer direction, and an opening to the other end of the inner ring. 3. The pipe joint structure according to claim 1, wherein a second tapered flow path is formed to connect the second transfer path in a state and the orifice flow path in a state where a cross-sectional area gradually changes in the fluid transfer direction. Fluid equipment.   The end portion on the root side with respect to the annular large diameter portion in the inner ring is fitted into the tubular portion or the device main body, and the tubular portion or the device main body and the inner ring at the inner fitting portion are connected. The fluid apparatus which has the pipe joint structure as described in any one of Claims 1-4 in which the back seal part closely_contact | adhered by the tightening by the screwing to the root side of the said tubular part of the said union nut is formed.   The back seal portion includes a seal surface formed by a tapered surface that gradually increases in diameter toward the outer side in the axial direction of the tubular portion or the device body, and a tapered surface formed at an end portion of the inner ring. The fluid device having the pipe joint structure according to claim 5, wherein the fluid device is formed by close contact with the protruding end surface. A cylinder formed at the end of the inner ring in the annular groove formed in parallel with the axis of the tubular portion on the outer side in the radial direction of the tubular portion or the sealing surface of the device body. The fluid apparatus which has the pipe joint structure of Claim 6 comprised by inserting a part.

Images