JP3074272U - Flexible tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible pipe in which a tubular connecting fitting having a pipe connecting function is inserted into an end of a flexible pipe material, by using a thin-walled pipe as the connecting fitting, thereby making the connecting fitting end face. Even if the formed step is made as small as possible, it is possible to provide the connection fitting with high rigidity. By holding the tube material by the connection fitting and the crimped outer cap, the joint strength between the connection fitting and the tube material is increased. SOLUTION: A ring-shaped reinforcing rib 3 formed on a connection fitting 3 by forming a cylindrical wall of the connection fitting into a bulging shape.
2 is provided. The pipe member 5 is clamped and held by the connection fitting 3 and the outer cap 6 crimped and reduced in diameter. It is desirable that the tube material 5 be covered with the protective jacket 7.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a flexible tube, and more particularly to a flexible tube that can be suitably used for a pipeline that requires a low flow resistance of a liquid.

[0002]

[Prior art]

 FIG. 6 is a half cut side view of a main part of a conventional flexible tube. In this flexible tube, a cylindrical connection fitting 1 having a pipe connection function is inserted into and held at an end of a flexible tube material 2. More specifically, a rubber hose or a resin hose is used for the flexible pipe member 2, and a plurality of serrated cross sections are provided at a plurality of locations on the outer periphery of the insertion region 11 of the connection fitting 1 press-fitted into the end of the tube member 2. Protrusions 12 for retaining are provided, and these protrusions 12 are locked to the inner peripheral portion of the tube 2 to prevent the connection fitting 1 from coming out of the tube 2. Further, a flange 13 is provided at the tip of the connection fitting 1, and the flange 13 prevents the cap nut 3 previously fitted to the connection fitting 1 from being pulled out. In this flexible pipe, when the cap nut 3 is screwed into a threaded connection port (not shown) provided on another pipe side and tightened, the pipe of the other pipe and the pipe material 2 are connected via the connection fitting 1. Is communicated.

In the conventional flexible tube described with reference to FIG. 6, a connection fitting 1 is press-fitted into an end portion of a flexible tube material 2, and a projection 12 of an insertion region 11 is formed inside the tube material 2. The connection fitting 1 is required to have such a rigidity that the shape of the connection fitting 1 is not deformed by press-fitting into the pipe material 2 because the connection fitting 1 is configured to be locked to the peripheral portion so as not to be pulled out. Therefore, in a conventional flexible tube, the connection fitting 1 is manufactured by cutting brass or other metal materials.

[0004]

[Problems to be solved by the invention]

 However, in the conventional flexible tube shown in FIG. 6, the connection fitting 1 is simply inserted into the end of the flexible tube material 2 in a press-fit manner so that the projection 12 is engaged with the inner surface 21 of the tube material 2. Therefore, when an external force is applied such that the connection fitting 1 and the tube 2 are strongly pulled away from each other, the connection fitting 1 may fall off from the end of the tube 2.

When the metal fitting 1 is manufactured by cutting a metal material, the thickness T1 of the tip 15 of the insertion region 11 of the metal fitting 1 cannot be reduced so much. A relatively large step is generated between the inner surface 21 of the tube member 2 and the inner surface 21 of the tube member 2 so as to match the thickness T1 of the tip 15 of the insertion region 11. For this reason, in the conventional flexible tube, the internal passage 16 of the connection fitting 1 becomes extremely narrower than the internal passage 22 of the tube material 2 due to the relatively large step, which causes a problem. The pressure loss of the water flow becomes large at the connection fitting 1, and the allowable flow rate of the pipe line is greatly affected by the width of the internal passage 16 of the connection fitting 1.

The present invention has been made in view of the above circumstances, and the use of a thin-walled tube of a predetermined length as a connection fitting minimizes the above-mentioned step and minimizes the pressure loss of the water flow as much as possible. Even if it does so, sufficient rigidity is given to the connection fitting. As a result, even if the pipe and the connection fitting are joined by using a method called “crimping”, the connection fitting does not deform, and the pipe and the pipe material are not deformed. Provided is a flexible tube in which even when an external force is applied so that the fittings inserted into the ends of the tube are strongly pulled away from each other, there is less possibility that the fittings will fall off from the end of the tube material as compared with the conventional case. The purpose is to

[0007]

[Means for Solving the Problems]

 In the flexible tube according to the present invention, a tubular connection fitting having a tube connection function is inserted into and held at an end of a flexible tube material. The pipe connection function provided in the connection fitting is also exhibited by attaching the cap nut 3 described in FIG. 6 to the connection fitting, but the means for providing the pipe connection function is not limited to this. For example, a male screw may be formed in the pipe connection fitting, and the male screw may be screwed into a female screw formed at the end of another pipe or a female screw of a joint connected to another pipe to be connected.

In the present invention, the tube is covered with a cylindrical protective jacket. The protective jacket preferably has a structure in which a thin metal wire such as a stainless steel thin wire is braided. In such a case, the protective jacket prevents the flexible pipe from being damaged or broken. In addition, the high shape retention of the protective jacket makes it less likely that the pipe material will be crushed flat and the water flow will be impaired.

In the present invention, a ring-shaped reinforcing rib formed by forming a cylindrical wall of the connection fitting into a bulging shape is provided in a region where the connection fitting is inserted into the pipe member. For this reason, the rigidity of the insertion region of the connection fitting is enhanced by the rib-shaped reinforcing ribs, and excellent shape retention or rigidity is imparted to the insertion region. Moreover, since the reinforcing ribs are formed by molding the cylindrical wall of the connection fitting into a bulging shape, the connection fitting is reinforced without increasing the number of parts, which helps to suppress an increase in cost. .

[0010] In the present invention, the pipe member and the protective jacket are provided between the insertion region of the connection fitting and a cylindrical exterior cap externally fitted to the connection fitting, and The pipe member and the protective jacket are clamped and held by the insertion region of the connection fitting and the outer cap reduced in diameter by crimping. As described above, when the pipe and the protective jacket are clamped and held by the insertion area of the connection fitting and the outer cap reduced in diameter by crimping, the joint strength between the pipe and the connection fitting is increased. As compared with the conventional flexible tube described above, the connection fitting 1 is simply inserted into the end portion of the pipe 2 in a press-fit manner, and the projection 12 is engaged with the inner surface 21 of the pipe 2. Is less likely to fall off the tubing. On the other hand, when the pipe is clamped and held between the outer cap and the connection fitting by the method of caulking the outer cap and reducing the diameter, a large radially inward force is applied to the connection fitting as described above. Since the ring-shaped reinforcing ribs are formed in the insertion region of the connection fitting, it is unlikely that the connection fitting is deformed even if the connection fitting is thin. Therefore, the pressure difference of the water flow can be suppressed as small as possible by reducing the step described at the beginning.

In the present invention, an inwardly protruding rim is provided at the front end of the outer cap, and the rim is formed by forming the cylindrical wall of the connection fitting into a bulging shape. It is desirable to engage with the outward convex portion located inside the outer cap. With this configuration, when the connection fitting is strongly pulled in a direction to come out of the end of the pipe, the rim of the outer cap holding the pipe is engaged with the outwardly protruding portion on the connection fitting side. Together, it helps to prevent the connection fitting from being pulled out of the tube.

In the present invention, the pipe member has a tube wall made of a synthetic resin having a helically extending rib having a smooth inner surface, and at the end of the tube wall, the rib is formed of a reinforcing rib of the connection fitting. It is desirable to be deployed on the front side. According to this, the pressure loss of the water flowing through the internal passage of the pipe material is reduced. Therefore, by using a thin-walled pipe for the connection fitting, the pressure loss is reduced in the entire pipe including the insertion point of the connection fitting, and the allowable flow rate of the pipe is greatly affected by the width of the internal passage of the connection fitting. Will not occur. Also, since the ribs on the tube side are provided at the ends of the pipe wall of the tube in front of the reinforcing ribs on the connecting member, the engagement between the ribs on the tube side and the reinforcing ribs makes it difficult for the connecting member to come off from the tube. Become.

[0013]

[Embodiment of the invention]

 1 is a half side view of a main part of a flexible tube A of the present invention, FIG. 2 is a partially enlarged sectional view of a tube material, FIG. 3 is a partially enlarged sectional view of a protective jacket, FIG. 4 is a partially enlarged sectional view of a connection fitting, FIG. 5 is a partially enlarged sectional view of the outer cap.

In the flexible tube A, a cylindrical connection fitting 3 having a pipe connection function is inserted into and held at an end of a flexible tube material 5. As shown in FIGS. 1 and 4, a thin short tube having a thickness of about 0.3 mm is used for the connection fitting 3. When the flexible tube A is used for water piping, it is desirable to use a stainless steel tube for the connection fitting 3 in order to prevent the adverse effects of rusting. As shown in FIG. 1, the connection fitting 3 has its base side inserted into the end of the tube material 5, and its insertion region 31 has a shape in which the cylindrical wall of the connection fitting 3 bulges outward in an arc shape. And a ring-shaped reinforcing rib 32 formed by molding. In the connection fitting 3 shown in the figure, two reinforcing ribs 32 and 33 are formed, and only one reinforcing rib 32 on the side closer to the base is located in the insertion area 31 described above. Another reinforcing rib 33 may be inserted into the end of the tube 5 together with the reinforcing rib 32. In such a case, the two reinforcing ribs 32 and 33 are located in the insertion region 31.

The connecting wall 3 has a cylindrical wall formed to protrude outward at a position closer to the distal end than the position where the two reinforcing ribs 32 and 33 are formed, specifically at a position substantially at the center in the longitudinal direction. By doing so, a ring-shaped outward convex portion 34 formed is formed. The outwardly projecting portion 34 in the illustrated example is formed by folding the bulging portion in an overlapping manner. Therefore, there is no recessed portion on the inner surface of the outward convex portion 34, which helps to reduce the flow resistance of water. Further, the height of the outwardly protruding portion 34 is slightly lower than the above-described reinforcing ribs 32 and 33.

As shown in FIG. 1, an outer cap 6 is fitted on the connection fitting 3. The exterior cap 6 has an inwardly protruding edge 61 at the front end, has an initial shape of a cylinder, and has an inner diameter in an initial state. It is larger than the outer diameter of the region 31 and the top outer diameter of the reinforcing ribs 32 and 33 formed in the insertion region 31 and the like.

Next, a flexible hose made of rubber or synthetic resin having a rib 51 having a smooth inner surface and extending spirally is used for the tube member 5. The inner diameter of the pipe member 5 in the initial state is equal to the outer diameter of the insertion region 31 of the connection fitting 3 and the top outer diameter of the reinforcing ribs 32 and 33 formed in the insertion region 31 and the like. Or slightly shorter or slightly longer than them. Such a flexible tubing 5 is covered with a protective jacket 7. The protective jacket 7 is formed by braiding a metal wire such as a stainless steel wire. Therefore, the protective tube 7 prevents the flexible tube 5 from being damaged or broken, and the high shape retention of the protective jacket 7 causes the tube 5 to be crushed flat and impairs the water flow. It is difficult to repel.

As shown in FIG. 1, a tube member 5 and a protective jacket 7 covering the tube member 5 include a portion including the insertion region 31 of the connection fitting 3, and a cylindrical exterior that is externally fitted to the connection fitting 3. As shown in the lower half of FIG. 1, the outer cap 6 is crimped into a polygon and reduced in diameter while being disposed between the cap 6 and the outer cap 6. As described above, the outer cap 6 is crimped and reduced in diameter, so that each end of the pipe 5 and the protective jacket 7 is sandwiched by the insertion region 31 of the connection fitting 3 and the outer cap 6 reduced in diameter by crimping. If the pressure is maintained, the pipe member 5 and the connection fitting 3 can be easily connected, and even if the two are pulled in the direction in which they are separated from each other, the connection fitting 3 can easily fall off from the end of the pipe 5. Absent.

When the outer cap 6 is crimped to reduce the diameter, a large radially inward force is applied to the insertion region 31 of the connection fitting 3, but the connection fitting 3 includes the insertion region 31. Since the portions are reinforced by the reinforcing ribs 32 and 33 to increase the rigidity, even if a thin metal short pipe is used for the connection fitting 3, a situation where the connection fitting 3 is deformed may occur. Absent.

Further, when a thin metal short tube is used for the connection fitting 3 as in this embodiment, the connection fitting 3 is thin, so that the inner surface 35 of the connection fitting 3 as shown in FIG. The step between the tube 5 and the smooth inner surface 52 becomes very small in proportion to the thickness of the connection fitting 3. Moreover, when the outer cap 6 is crimped, the flexible tubular material 5 is compressed, so that the insertion region 31 of the connection fitting 3 is buried in the inner peripheral portion of the tubular material 5. Not in a state. Therefore, the diameter of the internal passage 36 of the connection fitting 3 is substantially the same as the diameter of the internal passage 53 of the pipe member 5, and the allowable flow rate of the pipe is greatly affected by the width of the internal passage 36 of the connection fitting 3. No longer occurs.

Next, when the connection fitting 3 is strongly pulled in the pull-out direction from the end of the pipe 5, the rim 61 of the exterior cap 6 that presses the pipe 5 and the protective jacket 7 is connected to the connection fitting 3. It engages with the outwardly protruding portion 34 on the side to prevent the connection fitting 3 from being pulled out of the tube 5. As a result, even when the connection fitting 3 is strongly pulled in the pull-out direction from the end of the pipe 5 due to an earthquake or the like, a situation in which the connection fitting 3 falls off from the pipe 5 does not easily occur. Further, since the rib 51 on the tube 5 side is provided at the end of the tube wall of the tube 5 in front of the reinforcing rib 33 of the connection fitting 3, the connection is established by the engagement of the rib 51 on the tube 5 and the reinforcing rib 33. The metal fitting 3 is hard to fall out of the tube material 5.

As shown in FIG. 1, the distal end of the connection fitting 3 is provided with a flange 37 formed by forming a cylindrical wall of the connection fitting 3 into a bulging shape. The cap nut 8 that has been fitted to the outside 3 is prevented from being removed. In this flexible tube, when the cap nut 8 is screwed into a threaded connection port (not shown) provided on another tube side and tightened, the other tube and the pipe line of the tube material 2 are connected via the connection fitting 3. Is communicated.

[0023]

[Effect of the invention]

 As described above, according to the present invention, by using a thin-walled pipe of a predetermined length for the connection fitting, the step at the place where the connection fitting is inserted into the pipe material is made as small as possible, and the pressure loss of the water flow is reduced. Can be reduced as much as possible. Even if a thin pipe is used for the connection fitting, the connection fitting is given a sufficiently high rigidity. Therefore, even if the pipe and the connection fitting are joined by using a method called “crimping”, the connection fitting is deformed. Does not occur, and even when external force is applied to the pipe or the fittings inserted into the ends of the pipes that are strongly pulled away from each other, the fittings may fall off from the ends of the pipes as compared to the conventional case. Less. Nevertheless, since a separate component is not used to reinforce the connection fitting, it is possible to suppress the cost increase accordingly.

The flexible pipe according to the present invention can be used for extending a pipe or forming a bent portion in a pipe, and a joint for connecting pipes used for pipes. Also suitable for use as

[Brief description of the drawings]

FIG. 1 is a half cut side view of a main part of a flexible tube of the present invention.

FIG. 2 is a partially enlarged sectional view of a tube material.

FIG. 3 is a partially enlarged sectional view of a protective jacket.

FIG. 4 is a partially enlarged sectional view of a connection fitting.

FIG. 5 is a partially enlarged cross-sectional view of an exterior cap.

FIG. 6 is a half cut side view of a main part of a conventional flexible tube.

[Explanation of symbols]

 Reference Signs List A Flexible tube 3 Connection fitting 5 Tube material 6 Exterior cap 7 Protective jacket 31 Connection fitting insertion area 32, 33 Reinforcement rib 34 Outward protrusion 51 Rib 61 Edge

Claims (3)

[Utility model registration claims] 1. A flexible pipe in which a tubular connecting fitting having a pipe connecting function is inserted and held at an end of a flexible tubular material, wherein the tubular material is covered with a tubular protective jacket. A ring-shaped reinforcing rib formed by forming a cylindrical wall of the connection fitting into a bulging shape is provided in an insertion region of the connection fitting with respect to the pipe, and the connection between the pipe and the protective jacket is established. It is arranged between the insertion area of the metal fitting and the cylindrical outer cap externally fitted to the connection metal fitting,
A flexible tube characterized in that the tube and the protective jacket are clamped and held by the insertion region of the connection fitting and the outer cap reduced in diameter by crimping. 2. An inwardly protruding rim portion is provided at a front end of the outer cap, and the rim portion is formed by forming a cylindrical wall of the connection fitting into a bulging shape, and the outer cap is provided. 2. The flexible tube according to claim 1, wherein the flexible tube is engaged with an outward convex portion located inside the cap. 3. The pipe member has a tube wall made of a synthetic resin having a helically extending rib with a smooth inner surface, and the rib is provided at an end of the tube wall in front of a reinforcing rib of the connection fitting. The flexible tube according to claim 1, wherein the flexible tube is provided.