Hose connection coupler and hose connection structure

Abstract

To provide a hose connection coupler and a hose connection structure using the same capable of preventing damage of equipment even when the hose connection coupler is not removed from a pipe.SOLUTION: A hose connection coupler includes a body part provided with a hose joint at one end portion thereof, a pair of cams disposed at an interval in a radial direction of the main body portion, a cam holding portion attached to the main body portion so as to surround an outer surface on the other end portion side of the main body portion and holding each of the cams so as to be slidable in the radial direction of the main body portion, and a pair of springs biasing each of the cams in a central axis direction of the main body portion. When turning force larger than a predetermined magnitude is applied to the body part, weighting from a tubular part provided in a connection part of piping is concentrated on one side of the cam by the turning of the body part. Since the tubular part presses a second inclined part provided in the cam, and moves it in a direction away from the central axis of the body part so that the engagement between the other part of the cam and the tip part is released.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a hose connection coupler for connecting a hose to a pipe, and a hose connection structure using the same. [Background technology]

[0002] Railway vehicles are equipped with clean water tanks that store clean water for washing faces and hands (see, for example, Patent Document 1). Water is supplied to the clean water tank by connecting the water intake of the clean water tank to a clean water pipe using a hose equipped with a coupler at a vehicle depot or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6722418 Summary of the Invention [Problem to be solved by the invention]

[0004] The hose connection coupler according to the present invention is for connecting a hose to a connection part of a pipe having a tubular portion and an annular tip portion with an outer diameter larger than that of the tubular portion, the annular portion being provided at the tip end of the tubular portion via a step, and comprises a cylindrical main body portion having a hose joint at one end thereof, a pair of cams arranged at a distance from the other end of the main body portion and spaced apart in the radial direction of the main body portion, and a pair of cylindrical cams attached to the main body portion surrounding the outer surface of the other end of the main body portion and configured to allow each of the cams to slide in the radial direction of the main body portion. and a pair of springs housed in the cam holder and biasing each of the cams in the direction of the central axis of the main body with a predetermined pressing force, a first spherical surface portion is provided on the outer surface of the main body within a predetermined range from the other end of the main body, and a second spherical surface portion having the same curvature as the first spherical surface portion is provided on the inner surface of the cam holder, and the cam holder is attached to the main body in a state in which the first spherical surface portion and the second spherical surface portion are in close contact with each other and can slide, and each of the cams faces outward from the cam holder and becomes smaller as it approaches the other end of the main body. The cam holder has a first inclined surface whose distance from the central axis decreases, and a second inclined surface that faces the other end of the main body and is adjacent to the first inclined surface via a ridge line, and whose distance from the central axis of the main body decreases as it moves away from the other end of the main body. As the connecting portion of the piping is inserted into the cam holder, the tip of the connecting portion abuts against the first inclined surface of each of the cams and advances into the main body while pushing and spreading each of the cams in a direction away from the central axis of the main body. When the entire tip of the connecting portion passes through the ridge line of each of the cams, the cam is pushed by the biasing force of the spring. Each of the cams moves in the direction of the central axis of the main body, and each cam engages with the step in the connection part, thereby restricting separation in the direction of the central axis of the main body. When a force greater than a predetermined magnitude is applied to the main body to rotate the first spherical part, the tubular part of the connection part presses one of the cams, moving it in a direction away from the central axis of the main body, and the step part of the connection part presses the second inclined surface of the other cam, moving it in a direction away from the central axis of the main body, thereby releasing the engagement between the other cam and the tip part.

[0005] The hose connection structure of the present invention comprises a piping connection portion having a tubular portion and a ring-shaped tip portion having an outer diameter larger than that of the tubular portion and provided at the tip side of the tubular portion via a step, and the above-mentioned hose connection coupler. [Means for solving the problem]

[0006] When the water supply to the drinking water tank is completed, the valve is usually closed and the hose connection coupler is removed from the drinking water tank's intake port and piping. However, if the hose connection coupler is not removed by mistake and the vehicle is moved with the hose still connected to the drinking water tank and piping, there is a possibility that the drinking water tank and the piping at the vehicle depot will be damaged.

[0007] Therefore, an object of the present invention is to provide a hose connection coupler that can prevent damage to equipment even when tension is applied to the hose while the hose connection coupler is attached to the piping, and a hose connection structure using the same. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a hose connection coupler that can prevent damage to equipment even when tension is applied to the hose while the hose connection coupler is attached to a pipe, and a hose connection structure using the same. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a state before connection of a hose connection structure according to an embodiment; [Figure 2] Schematic cross-sectional view showing the process of connecting a hose connection coupler to a pipe [Figure 3] Schematic cross-sectional view showing the process of removing a hose connection coupler from a pipe [Figure 4] Schematic cross-sectional view showing a process subsequent to FIG. 3. [Figure 5] A schematic cross-sectional view showing a state in which a rotational force is applied to a hose connection coupler connected to a pipe. [Figure 6]Enlarged view of the left cam area shown in Figure 5 DETAILED DESCRIPTION OF THE INVENTION

[0010] FIG. 1 is a schematic cross-sectional view showing a hose connection structure according to an embodiment in a state before connection.

[0011] The hose connection structure 100 comprises a coupler 10 for connecting a hose and a connection portion 20 for piping.

[0012] The piping connection portion 20 is a connection portion of a hose attached to a water distribution pipe for supplying industrial water or clean water, or to a water distribution pipe for discharging wastewater. The connection portion 20 may be a water intake port attached to a water tank or a drain port attached to a wastewater tank. Valves, open / close cocks, etc. (not shown) are appropriately provided along the piping. The connection portion 20 includes a tubular portion 21 and an annular tip portion 22, which is located adjacent to the tip of the tubular portion 21 and has a larger outer diameter than the tubular portion 21. A step 8 is formed at the connection portion between the tubular portion 21 and the tip portion 22 due to the difference in outer diameter. The step 8 is the portion where cams 2a and 2b of the hose connection coupler 10, which will be described later, engage. An annular release ring 23 is provided to surround the outer peripheral surface of the tubular portion 21. The release ring 23 is attached to the tubular portion 21 so as to be slidable along the outer peripheral surface of the tubular portion 21 in the central axial direction of the tubular portion 21. The release ring 23 is a member for releasing the connection of the hose connection structure 100, and will be described in detail later.

[0013] The hose connection coupler 10 is used to detachably connect a hose (not shown) attached to a hose fitting 13 to a piping connection part 20. The hose connection coupler 10 includes a main body 1, a pair of cams 2a and 2b, a cam holder 3, and springs 4a and 4b.

[0014] The main body 1 has a hollow cylindrical shape as a whole, and is provided with a hose coupling 13 at one end (the lower end in FIG. 1 ). A spherical first spherical portion 11 is provided on the outer surface of the main body 1 within a predetermined range from the other end (the upper end in FIG. 1 ). In this embodiment, the main body 1 is composed of a cylindrical first divided body including the hose coupling 13 and an annular second divided body including the first spherical portion 11, and a packing 19 is sandwiched between the first divided body and the second divided body to seal any gaps at the joint. A packing 18 is provided on the inner periphery of the second divided body to seal any gaps at the joint between the outer periphery of the connecting portion 20 of the pipe and the main body 1 when the connecting portion 20 is connected.

[0015] The cams 2a and 2b are arranged at a distance from the other end of the main body 1 and spaced apart in the radial direction of the main body 1. The cams 2a and 2b are preferably arranged point-symmetrically with respect to the central axis Ax of the main body 1.

[0016] Cam 2a has a first inclined surface 15a facing outward from cam holder 3 and a second inclined surface 16a facing the other end of main body 1. First inclined surface 15a and second inclined surface 16a are adjacent to each other, and a ridge line 17a is formed where they connect. Similarly, cam 2b has a first inclined surface 15b facing outward from cam holder 3 and a second inclined surface 16b facing the other end of main body 1. First inclined surface 15b and second inclined surface 16b are adjacent to each other, and a ridge line 17b is formed where they connect.

[0017] Both of the first inclined surfaces 15a and 15b are curved surfaces or flat surfaces whose distance from the central axis Ax of the main body 1 continuously decreases as they approach the other end of the main body 1. Both of the second inclined surfaces 16a and 16b are curved surfaces or flat surfaces whose distance from the central axis Ax of the main body 1 continuously decreases as they move away from the other end of the main body 1 (toward the outside of the cam holding portion 3).

[0018] The cam holder 3 has an overall cylindrical shape and is attached to the main body 1, surrounding the outer surface (first spherical portion 11) of the other end of the main body 1. The cam holder 14 has a cam accommodating portion 14a that accommodates the cam 2a and spring 4a, and a cam accommodating portion 14b that accommodates the cam 2b and spring 4b. The cams 2a and 2b are slidable in the radial direction of the main body 1 within the cam accommodating portions 14a and 14b, respectively. The inner surface of the cam holder 3 is provided with a second spherical portion 12 that has the same curvature as the first spherical portion 11 provided on the main body 1. The cam holder 3 is attached to the main body 1 with the first spherical portion 11 and second spherical portion 12 of the main body 1 in close contact with each other and slidable against each other.

[0019] The springs 4a and 4b are housed in the cam holding portion 3 and urge the cams 2a and 2b, respectively, with a predetermined urging force F in the direction of the central axis Ax of the main body 1. The springs 4a and 4b are maintained inside the cam housing portions 14a and 14b by an annular spring presser cover 5 attached to the cam holding portion 3.

[0020] A shear pin 6 is provided between the main body 1 and the cam holder 3, connecting the first spherical portion 11 and the second spherical portion 12. More specifically, the cam holder 3 has a through-hole that penetrates from the outer surface to the second spherical portion 12, and the main body 1 has a hole that has an opening in the first spherical portion 11 and is continuous with the through-hole provided in the cam holder 3. The shear pin 6 is inserted into the through-hole of the cam holder 3 and the hole in the main body 1, and the relative rotation between the main body 1 and the cam holder 3 is restricted. However, when a rotational force of a predetermined magnitude or greater (torque of a predetermined value or greater) is applied around the center of the first spherical portion 11, the shear pin 6 breaks due to shear fracture, allowing the main body 1 and the cam holder 3 to rotate relative to each other.

[0021] A check valve 9 is provided inside the main body 1 according to this embodiment. The check valve 9 includes a substantially plate-shaped closing plate 31 and a cylindrical portion 32 that is disposed on the other end side of the main body 1 and is connected to the closing plate 31. The check valve 9 is movable in the direction of the central axis Ax of the main body 1 and is biased by a spring (not shown) or the like so as to be disposed in the position shown in FIG. 1 when the main body 1 is not connected to the connection portion 20 of the pipe. The closing plate 31 of the check valve 9 closes the flow path of the main body 1 (the opening on the other end side of the main body 1) when the main body 1 is not connected to the connection portion 20 of the pipe. On the other hand, the closing plate 31 of the check valve 9 opens the flow path of the main body 1 (the opening on the other end side of the main body 1) when the main body 1 is connected to the connection portion 20 of the pipe (when the cams 2a and 2b are each engaged with the step 8 of the connection portion 20 of the pipe).

[0022] A method of using the hose connection structure according to this embodiment will be described below.

[0023] FIG. 2 is a schematic cross-sectional view showing a process of connecting a hose connection coupler to a pipe.

[0024] To connect the hose connection coupler 10 to the connection portion 20 of the pipe, first, from the positional relationship shown in FIG. 1, the hose connection coupler 10 is brought close to the connection portion 20 of the pipe, and the tip portion 22 of the connection portion 20 is inserted into the cam holder 3. As the tip portion 22 of the connection portion 20 is inserted into the cam holder 3, the tip portion 22 of the connection portion 20 abuts against the first inclined surfaces 15a and 15b of the cams 2a and 2b, respectively, as shown in FIG. 2(a). The tip portion of the connection portion 20 also abuts against the cylindrical portion 32 of the check valve 9.

[0025] 2(b), when the hose connection coupler 10 is further pushed into the piping, the tip 22 of the connection part 20 enters the inside of the main body 1 while pushing the cams 2a and 2b apart in directions away from the central axis Ax of the main body 1. The tip 22 of the connection part 20 also moves the check valve 9 toward the hose joint 13.

[0026] When the hose connection coupler 10 is further pushed into the piping and the entire tip 22 of the connection portion 20 passes over the ridges 17a and 17b of the cams 2a and 2b, the urging force of the springs 4a and 4b returns the cams 2a and 2b to their initial positions in the axial direction of the main body 1, as shown in FIG. 2(c). This causes the cams 2a and 2b to engage with the step 8 of the connection portion 20. In this state, the step 8 of the connection portion 20 abuts against the second inclined surfaces 16a and 16b of the cams 2a and 2b, restricting the main body 1 from separating in the axial direction. Furthermore, the tip 22 of the connection portion 20 pushes the check valve 9 toward the hose fitting 13, thereby opening the flow path of the main body 1. The gap at the joint between the connection portion 20 and the main body 1 is closed by the packing 18.

[0027] As described above, by placing the hose connection coupler 10 against the connection part 20 of the pipe and pushing it in, the hose connection coupler 10 can be attached to the connection part 20 of the pipe, and movement of the hose connection coupler 10 toward the main body 1 in the direction of the central axis Ax can be locked.

[0028] 3 and 4 are schematic cross-sectional views showing a process of removing the hose connection coupler from the pipe.

[0029] To remove the hose connection coupler 10 from the connection part 20 of the pipe, from the state shown in Fig. 2(c), the release ring 23 provided on the connection part 20 is slid toward the hose connection coupler 10 and inserted into the gap between the tubular part 21 and the cam holding part 3 as shown in Fig. 3(a). As a result, as the release ring 23 is inserted, the tip of the release ring 23 comes into contact with the first inclined surfaces 15a and 15b of the cams 2a and 2b.

[0030] When the release ring 23 is further pushed into the hose connection coupler 10, as shown in Figure 3(b), the tip of the release ring 23 pushes the cams 2a and 2b apart in directions away from the central axis Ax of the main body 1, and moves them to positions where they do not interfere with the tip 22 of the connecting part 20. This releases the engagement between the cams 2a and 2b and the step 8 of the connecting part 20.

[0031] Next, as shown in FIGS. 3(c) to 4(b), with the release ring 23 still in contact with the step 8 of the connection part 20, the hose connection coupler 10 is pulled away from the connection part 20 of the piping.

[0032] Through the above steps, the hose connection coupler 10 can be removed from the piping connection part 20, and the state shown in Fig. 1 can be restored. As the tip 22 of the connection part 20 is pulled outward from the hose connection coupler 10, the check valve 9 moves outward from the cam holding part 3 due to the biasing force of a spring or the like (not shown), and when the tip 22 of the connection part 20 moves away from the cylindrical part 32 of the check valve 9 as shown in Fig. 4(b), the closing plate 31 of the check valve 9 closes the flow path of the main body 1.

[0033] Next, the operation when a force is applied to the main body 1 of the hose connecting coupler 10 while the hose connecting coupler 10 is connected to the connecting portion 20 of the pipe will be described.

[0034] FIG. 5 is a schematic cross-sectional view showing a state in which a rotational force is applied to a hose connection coupler connected to a pipe, and FIG. 6 is an enlarged view of the vicinity of the left cam shown in FIG.

[0035] As described above, for example, in a vehicle depot, after the clean water tank of a railcar is connected to the connection portion 20 of the water supply pipe of the railcar depot using the hose connection coupler 10, a case may be imagined in which the railcar is moved without being detached. When a hose (not shown) connected to the hose connection coupler 10 is pulled in a direction oblique to the central axis Ax of the main body 1, the hose connection coupler 10 is subjected to a force in the direction of the central axis Ax of the main body 1 (the direction of the central axis of the pipe connection portion 20) and a force in a direction intersecting the central axis Ax. Because the main body 1 and the cam holder 3 are joined with the first spherical portion 11 and the second spherical portion 12, which have the same curvature, in contact with each other, the force in the direction intersecting the central axis Ax of the main body 1 becomes a rotational force that rotates the first spherical portion 11.

[0036] As an example, let us consider a case in which a rotational force is applied to the hose connection coupler 10 in the clockwise direction in FIG. 5 around the center Z of the first spherical portion 11. Because the main body 1 and the cam holding portion 3 are connected by the shear pin 6, the main body 1 does not rotate if the torque applied to the hose connection coupler 10 is less than a predetermined magnitude. If the torque applied to the hose connection coupler 10 exceeds a predetermined magnitude, the shear pin 6 breaks due to shear fracture. When the shear pin 6 breaks, the main body 1 rotates, and one cam 2b is pushed into the cam accommodating portion 14b, as shown in FIG. 5. A load is concentrated on the other cam 2a from the stepped portion of the tip 22 of the connecting portion 20. Because the contact point of tip end 22 of cam 2a is second inclined surface 16a described above, a component of the force applied from tip end 22 of connection portion 20 to second inclined surface 16a (a component of force in the left direction in FIG. 5 ) moves cam 2a inward into cam accommodating portion 14a, disengaging cam 2a from tip end 22 of connection portion 20. When cam 2a is disengaged, the clockwise rotational force applied to hose connection coupler 10 and the force in the central axis direction of piping connection portion 20 also disengage cam 2b from tip end 22 of connection portion 20. When the two cams 2a and 2b are disengaged from tip end 22 of connection portion 20, the force applied to hose connection coupler 10 in the central axis direction of piping connection portion 20 causes hose connection coupler 10 to separate from piping connection portion 20.

[0037] 6, the force applied to cam 2a from the tip of connection portion 20 (the force in the direction of the central axis of piping connection portion 20) is defined as W, the biasing force of spring 4a is defined as F, and the inclination angle of second inclined surface 16a (the angle that second inclined surface 16a forms with respect to a plane perpendicular to central axis Ax of main body 1 in a non-rotating state) is defined as θ. Since the lateral component of force W applied to second inclined surface 16a is W tan θ, if the value of θ is set so that W tan θ > F, i.e., so that tan θ > F / W, is satisfied for the assumed value of force W and the biasing force F of the spring, the connection between hose connection coupler 10 and piping connection portion 20 can be automatically released when the hose is pulled in an oblique direction.

[0038] As described above, in the hose connection coupler 10 according to this embodiment, the main body 1 and the cam holder 3 are coupled together with the first spherical portion 11 and the second spherical portion 12 in contact with each other, the first spherical portion 11 is rotatable, and the second inclined surfaces 16a and 16b are provided on the cams 2a and 2b for engaging with the piping connection portion 20. As a result, when the hose connection coupler 10 is pulled in a direction oblique to the central axis Ax and a torque equal to or greater than a predetermined value is applied to the first spherical portion 11, the main body 1 rotates, concentrating the load on the second inclined surface of one of the cams and disengaging the cams. Therefore, for example, if the hose connection coupler 10 is used to connect a tank or the like of a railway vehicle to the piping connection portion 20 at a railroad depot, even if the railway vehicle is moved without the hose connection coupler 10 being removed and the hose is pulled obliquely, the hose connection coupler 10 can be automatically detached from the piping connection portion 20. This can prevent damage to the piping equipment at the vehicle depot and equipment such as tanks on the railway vehicle side.

[0039] Furthermore, the main body 1 and the cam holder 3 are connected by a shear pin that breaks when a certain torque is applied, preventing the main body 1 from rotating unnecessarily. However, the shear pin 6 can be omitted. Furthermore, if the shear pin 6 is fixed with the pin retainer bolt 7 as in this embodiment, it can be easily replaced if it breaks.

[0040] Furthermore, the hose connection coupler 10 according to this embodiment is equipped with a check valve 9. When used to supply water from a hose connected to the hose connection coupler 10 to a connected pipe, the water can be stopped when the hose connection coupler 10 is detached from the connection part 20 of the pipe, so that flooding of the surrounding area can be prevented if the hose connection coupler 10 is unexpectedly detached due to the hose being pulled diagonally.

[0041] In the above embodiment, a configuration with two cams has been described, but the number of cams may be three or more as long as the engagement between the cam and the connection portion of the piping can be released when the hose is pulled diagonally.

[0042] In addition, in this embodiment, an example has been described in which the present invention is applied to a coupler attached to a hose for connecting a tank on a railway vehicle to piping at a vehicle depot, but the present invention can also be applied to couplers for connecting water tanks, sewage tanks, fuel tanks, waste liquid tanks, etc. of vehicles other than railway vehicles to piping of fixed equipment. [Industrial Applicability]

[0043] The present invention relates to a hose connection coupler for connecting a hose to a pipe, and a hose connection structure using the same. [Explanation of symbols]

[0044] 1 Main body 2a, 2b cam 3 Cam holder 4a, 4b springs 6 Shear Pin 8 steps 9. Check valve 10 Hose connection coupler 11 First spherical part 12 Second spherical part 13 Hose fittings 14a, 14b Cam housing 15a, 15b First inclined surface 16a, 16b Second inclined surface 17 Ridgeline 20 Piping 21 Tubular part 22 Tip 100 hose connection structure

Claims

1. A hose connection coupler for connecting a hose to a connection part of a pipe having a tubular portion and an annular tip portion provided at a tip side of the tubular portion via a step and having an outer diameter larger than that of the tubular portion, a main body having a cylindrical shape and a hose joint provided at one end thereof; a pair of cams arranged at a distance from the other end of the main body portion in a radial direction of the main body portion; a cam holding portion having a cylindrical shape, surrounding an outer surface of the other end side of the main body portion and attached to the main body portion, and holding each of the cams so that they are slidable in a radial direction of the main body portion; a pair of springs housed in the cam holding portion and biasing each of the cams with a predetermined pressing force in the central axis direction of the main body portion; a first spherical portion having a spherical shape is provided on an outer surface of the main body portion within a predetermined range from the other end portion, a second spherical surface portion having the same curvature as the first spherical surface portion is provided on an inner surface of the cam holding portion, the cam holder is attached to the main body in a state in which the first spherical portion and the second spherical portion are in close contact with each other and are slidable, Each of the cams a first inclined surface facing outward from the cam holding portion, the distance from the first inclined surface to the central axis of the main body decreasing as the first inclined surface approaches the other end of the main body; a second inclined surface facing the other end of the main body portion and adjacent to the first inclined surface via a ridge line, the distance from the central axis of the main body portion decreasing with increasing distance from the other end of the main body portion, As the connection portion of the piping is inserted into the cam holding portion, the tip end of the connection portion abuts against the first inclined surface of each of the cams, and enters the inside of the main body portion while pushing each of the cams apart in a direction away from the central axis of the main body portion. When the entire tip end of the connection portion passes over the ridge line of each of the cams, the urging force of the spring causes each of the cams to move in the direction of the central axis of the main body portion, and each of the cams engages with the step of the connection portion, thereby restricting separation in the direction of the central axis of the main body portion. a hose connection coupler in which, when a force greater than or equal to a predetermined magnitude is applied to rotate the first spherical portion relative to the main body portion, the tubular portion of the connection portion presses against one of the cams, moving it in a direction away from the central axis of the main body portion, and the stepped portion of the connection portion presses against the second inclined surface of the other of the cams, moving it in a direction away from the central axis of the main body portion, thereby releasing the engagement between the other of the cams and the tip portion.

2. 2. The hose connection coupler according to claim 1, wherein the main body and the cam holder are connected by a shear pin that breaks the first spherical portion when a torque equal to or greater than a predetermined magnitude is applied to the first spherical portion.

3. 2. The hose connection coupler according to claim 1, further comprising a check valve that closes the flow path of the main body portion when the coupler is not connected to the piping, and that opens the flow path of the main body portion when the connection portion of the piping is inserted inside the cam holder and each of the cams engages with the step of the piping.

4. A hose connection structure, a piping connection portion having a tubular portion having a tubular shape and an annular tip portion provided at a tip side of the tubular portion via a step and having an outer diameter larger than that of the tubular portion; a hose connection coupler for connecting a hose to the connection portion of the piping, The hose connection coupler is a main body having a cylindrical shape and a hose joint provided at one end thereof; a pair of cams arranged at a distance from the other end of the main body portion in a radial direction of the main body portion; a cam holding portion having a cylindrical shape, surrounding an outer surface of the other end side of the main body portion and attached to the main body portion, and holding each of the cams so that they are slidable in a radial direction of the main body portion; a pair of springs housed in the cam holding portion and biasing each of the cams with a predetermined pressing force in the central axis direction of the main body portion; a first spherical portion having a spherical shape is provided on an outer surface of the main body portion within a predetermined range from the other end portion, a second spherical surface portion having the same curvature as the first spherical surface portion is provided on an inner surface of the cam holding portion, the cam holder is attached to the main body in a state in which the first spherical portion and the second spherical portion are in close contact with each other and are slidable, Each of the cams a first inclined surface facing outward from the cam holding portion, the distance from the first inclined surface to the central axis of the main body decreasing as the first inclined surface approaches the other end of the main body; a second inclined surface facing the other end of the main body portion and adjacent to the first inclined surface via a ridge line, the distance from the central axis of the main body portion decreasing with increasing distance from the other end of the main body portion, As the connection portion of the piping is inserted into the cam holding portion, the tip end of the connection portion abuts against the first inclined surface of each of the cams, and enters the inside of the main body portion while pushing each of the cams apart in a direction away from the central axis of the main body portion. When the entire tip end of the connection portion passes over the ridge line of each of the cams, the urging force of the spring causes each of the cams to move in the direction of the central axis of the main body portion, and each of the cams engages with the step of the connection portion, thereby restricting separation in the direction of the central axis of the main body portion. a hose connection structure in which, when a force equal to or greater than a predetermined magnitude is applied to rotate the first spherical portion relative to the main body portion, the tubular portion of the connection portion presses against one of the cams, moving it in a direction away from the central axis of the main body portion, and the stepped portion of the connection portion presses against the second inclined surface of the other of the cams, moving it in a direction away from the central axis of the main body portion, thereby releasing the engagement between the other of the cams and the tip portion.

Images