JPH0212318B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hose joint that is attached to the end of a rubber hose or the like. More specifically, the present invention relates to a hose joint having a structure in which the socket part is pressed toward the center from the outside of the hose and caulked, and the end part of the hose is compressed between the socket part and the nipple part. INDUSTRIAL APPLICATION This invention can be utilized for the joint for the hose used for high pressure fluid equipment, such as a power steering and a hydraulic brake, for example.

[Prior Art] Hose joints, particularly hose joints used in high-pressure fluid equipment, are required to have improved leakage pressure. Therefore, conventional hose joints with the structure shown in FIG. 7a (publication of Utility Model Publication No. 55-39910), hose joints with the structure shown in FIG.
A hose joint having the structure shown in Figure a is provided as a typical example. In the hose joint shown in FIG. 7a, the outer peripheral surface of the nipple portion 100 is provided with a plurality of annular grooves 101 extending in the circumferential direction and arranged in series in the axial direction. In this hose joint, with the end of the hose 120 inserted into the space between the nipple part 100 and the socket part 110, the socket part 110 is pressed toward the center of the socket part 110 and crimped. By this caulking, a portion 111 of the socket portion 110 corresponding to the annular groove 101 is reduced in diameter, and thereby the hose 1
The rubber portion on the inner peripheral surface side of the hose 120 is pushed into the annular groove 101 in the direction of arrow E, that is, along the centripetal direction of the hose 120, thereby increasing the leakage pressure. In the hose joint shown in FIG. 7a, the relationship between the hose tightening rate and the leakage pressure was as shown by the white ▽ mark in FIG. 6.

Next, in the hose joint shown in FIG. 8a, the outer peripheral surface of the nipple portion 150 has an annular groove 1 extending in the circumferential direction.
51 are provided in series in the axial direction. Further, the inner circumferential surface of the socket portion 160 is provided with a ring-shaped second protruding portion 161 at a position facing the annular groove 151 of the nipple portion 150. Here, in the hose joint shown in FIG. 8a, with the end of the hose 120 inserted into the space between the nipple part 150 and the socket part 161, the socket part 160 is pressed in the centripetal direction of the socket part 160. Then caulk. By this caulking, the rubber portion on the inner peripheral surface side of the hose 120 is pushed into the annular groove 151 by the second protruding portion 161 of the socket portion 160, thereby increasing the leakage pressure. For the hose joint shown in Figure 8a, the relationship between the hose tightening rate and the leakage pressure is as shown by the black filled ▼ mark in Figure 6, and for the hose joint shown in Figure 7. There was almost no difference from the joint.

Next, in the hose joint shown in FIG. 9a, the outer circumferential surface of the nipple part 130 has a plurality of first protrusions 133 arranged in series around the central axis 130b of the nipple part 130.
Equipped with: The first protruding portion 133 includes a ring-shaped vertical surface 131 that is substantially perpendicular to the central axis 130b and extends in the circumferential direction;
A ring-shaped conical frustum surface 13 whose diameter gradually decreases from the outer peripheral end toward the tip 130a of the nipple portion 130.
It is formed by 2. Further, the inner peripheral surface of the socket portion 140 is provided with a ring-shaped second protrusion portion 141. This second protrusion portion 141 substantially faces the tip end side portion 132a of the ring-shaped conical truncated surface 132. Here, in the hose joint shown in FIG. 9a,
With the end of the hose 120 inserted into the space between the nipple part 130 and the socket part 140, the socket part 140 is pressed in the centripetal direction of the socket part 140 and caulked. By this caulking, the second protrusion 141 of the socket portion 140 and the rear end portion 132a of the ring-shaped conical surface 132 squeeze the rubber portion on the inner peripheral surface side of the hose 120, thereby reducing leakage pressure. It's increasing. The leakage pressure of the hose joint shown in FIG.
It was as shown in the black circle in the figure.

[Problems to be Solved by the Invention] In the conventional hose joint described above, the annular groove 1
01, the annular groove 151, and the truncated cone surface 132, the rubber is pushed into the recess formed by the cone surface 132, so that the required leakage pressure can be ensured. However, in the industry, efforts are being made to develop hose fittings that can ensure even higher leakage pressures.

The present invention has been made in view of the circumstances,
The object is to provide a coupling for a hose that can further increase leakage pressure.

[Means for Solving the Problems] The hose joint of the present invention includes: a nipple portion having a central through hole and inserted into the central hole of the hose; covering the nipple portion concentrically with the nipple portion; In a hose joint having a socket portion with an opening at one end into which the hose is inserted, the outer circumferential surface of the nipple portion extends in the circumferential direction substantially perpendicular to at least two central axes arranged in series in the axial direction. a ring-shaped first protrusion formed of a ring-shaped vertical surface and a ring-shaped truncated conical surface similar to a trapezoidal outer peripheral surface whose diameter decreases from the outer peripheral end of the vertical surface toward the tip of the nipple part; and the vertical surface of the first protrusion of one and the tip of the ring-shaped conical truncated surface of the other first protrusion on the rear end side of the first protrusion of one. and one annular groove extending in the circumferential direction provided between the sockets, and the inner circumferential surface of the socket portion includes at least one ring-shaped cone of each of the first protrusions of the nipple portion. The hose is configured to include a ring-shaped second protruding portion facing the rear end side portion of the base, and one end of the hose is inserted between the nipple portion and the socket portion, and the socket portion is moved toward the center. By pressing and caulking, the hose is held between each of the first protrusion portions and the second protrusion portions, and the inner peripheral surface side portion of the hose is pressed against the diameter of the ring-shaped truncated conical surface. The sealing effect is improved by causing flow deformation toward the smaller diameter side and pushing the ring-shaped frustum surface into the annular groove of the nipple portion from the smaller diameter side. The hose joint of the present invention will be further explained below.

The hose joint of the present invention includes a nipple portion and a socket portion provided concentrically with the nipple portion. Here, the nipple portion and the socket portion may be separate bodies, but the nipple portion and the socket portion may be provided coaxially and integrally.

The nipple part, which is a component of the present invention, is a rigid cylindrical member that is inserted into the central hole of the hose from its tip, and has a central through hole through which fluid such as driving oil and air passes. The hose is generally connected to a mating member, such as hydraulic equipment, via the nipple. Therefore, the other end of the nipple portion is generally formed with a connecting portion that is connected to a mating device.
When the hose and the mating member are connected through the nipple portion, fluid such as driving oil or air sent from the hose is sent to the mating member through the central through hole of the nipple portion.

The outer circumferential surface of the nipple portion includes a ring-shaped first protrusion portion and an annular groove. The first protrusion portion has a ring-shaped vertical surface that is substantially perpendicular to the central axis of the nipple portion and extends in the circumferential direction thereof, and a ring-shaped truncated conical surface that extends from the outer peripheral end of the vertical surface toward the tip of the nipple portion. It is formed. Here, the ring-shaped truncated cone surface is the same as or similar to the outer peripheral surface of a truncated cone whose diameter decreases from the outer peripheral end of the vertical surface toward the tip of the nipple portion. A typical form similar to the trapezoidal outer circumferential surface is an outer circumferential surface in which the diameter does not decrease linearly toward the tip of the nipple portion, such as a quadratic curve. The angle of inclination of the ring-shaped conical surface with respect to the axial direction is selected depending on the type of hose joint, but is generally preferably about 15 to 40 degrees. The rear end side portion of the ring-shaped truncated cone surface is preferably a flat surface that is parallel or substantially parallel to the axial direction of the socket portion.

At least two first protrusions are formed in series in the axial direction of the nipple part. In general, it is preferable that about 2 to 4 first protrusions are formed adjacent to each other.

The annular groove described above is a single groove extending in the circumferential direction of the nipple portion. The annular groove is formed between a vertical surface of one of the first protrusions and a ring of the other first protrusion on the rear end side of the first protrusion. It is provided between the tip of the truncated conical surface. The depth and width of the annular groove are appropriately selected depending on the type of hose joint.

FIG. 1 is a conceptual diagram of essential parts of a nipple portion according to an embodiment of the present invention. In FIG. 1, 1 is a ring-shaped first protrusion, which consists of a ring-shaped vertical surface 2 that is almost perpendicular to the central axis of the nipple and extends in the circumferential direction, and a nipple that extends from the outer peripheral end of the vertical surface 2. It is formed with a ring-shaped conical truncated surface 3 whose diameter decreases toward the tip of the section. Reference numeral 4 denotes an annular groove, which is formed by a vertical surface 2 of the first protruding part 1 and a ring-shaped conical truncated surface 3 of the other first protruding part 1 on the rear end side of the first protruding part 1.
is provided between the tip of the Here, the length L0 of the first protruding portion 1 is preferably about 2 to 5 mm, and can be, for example, about 3.5 mm. Rear end side portion 3a of ring-shaped conical truncated surface 3
are parallel or nearly parallel to the central axis of the nipple portion. The length L2 of this rear end side portion 3a is L2=
(1/2 to 1/3) It is preferable to set it to about L0. Also, the height t0 from the bottom of the annular groove 4 to the top of the vertical surface 2
Although it is selected depending on the type of hose joint, it can generally be about 0.5 to 0.8 mm, and preferably about 0.6 mm. The axial length dimension P of the annular groove 4 is selected depending on the type of hose joint, but generally when L0 is about 3.5 mm, it can be set to 1.0 to 2.0 mm, particularly 1.5 mm. Preferably, it is on the order of millimeters. As shown in FIG. 1, the outer end 2a of the vertical surface 2 is preferably rounded in order to prevent the rubber from breaking.

The socket portion, which is another component of the present invention, is a cylindrical member made of a material that can be plastically worked. This socket portion has an inner diameter larger than the outer diameter of the nipple portion. The inner circumferential surface of the socket portion is provided with a ring-shaped second protrusion. The ring-shaped second protrusion portion is provided at a position facing the rear end side portion of each ring-shaped truncated cone surface of each first protrusion portion of the nipple portion. The height and width of the second protrusion are appropriately selected depending on the type of hose joint, but the height is preferably about 0.5 to 1.5 mm, and the axial width is preferably about 1 to 3 mm. In addition to the second protrusion, other protrusions may be provided on the inner circumferential surface of the socket portion, if necessary. The hose may be a known hose such as a rubber hose or a plastic hose, preferably one having a structure in which a reinforcing layer is embedded.

Now, a typical method for connecting the hose joint of the present invention to the end of a hose will be described. First, with the end of the hose inserted into the space between the nipple part and the socket part, the socket part is pressed in the centripetal direction of the socket part using a caulking tool or the like. Then, the socket part is plastically deformed by this pressing, and the socket part is caulked and fastened. In this case, it is generally preferable to press the center part of the socket part, leaving both axial ends of the socket part intact. When caulked, the end of the hose is held between the first protrusion and the second protrusion, and the inner circumference side of the end of the hose becomes a ring-shaped conical due to its own elasticity. It flows along the platform and is pushed into the annular groove.

[Effects of the Invention] If the hose joint of the present invention is used, the hose can be held between each of the first protruding parts and the second protruding parts, and the inner peripheral surface of the hose can be held in the annular groove of the nipple part. I try to push the parts in. Therefore, the filling rate of the hose portion within the annular groove can be increased, and the sealing effect can be improved. The reason why the filling rate of the hose portion in the annular groove can be increased in this way is presumed to be as follows. That is, the first reason why the hose portion flows along the surface of the ring-shaped conical cone and is pushed into the annular groove, and the first reason why the hose portion flows along the ring-shaped frustum surface and is pushed into the annular groove; Since the hose is held under strong pressure by the two protrusions, the second reason that it is difficult for the hose to escape works synergistically, and as a result, the hose inside the annular groove is filled. It is presumed that the sealing effect will be dramatically improved. Therefore, in the present invention, as shown in the examples described later, an extremely high leakage pressure of 200 Kgf/mm ² or more, particularly 350 Kgf/mm ^{2 or} more can be obtained. Here, the leakage pressure means the pressure when fluid leaks from between the nipple part and the socket part.

[Embodiment] FIGS. 2 to 4 show a first embodiment of the present invention. First, the nipple portion 6, which is the main component of the hose joint of the first embodiment, will be described. The nipple part 6 is a member mainly having a cylindrical part, and has a central through hole 6c through which fluid such as driving oil and air flows. This nipple part 6 is made of iron so as to have rigidity.
It is made from aluminum or hard resin. As shown in FIG. 3, the outer peripheral surface of the nipple portion 6 includes a plurality of ring-shaped first protrusions 7, 17, 27 provided in series in the axial direction of the nipple portion 6, and extending in the circumferential direction. One annular groove 8 is provided.

The first protruding portions 7, 17, 27 have ring-shaped vertical surfaces 9, 19, 29 that are substantially perpendicular to the central axis 6a of the nipple portion 6 and extend in the circumferential direction, and ring-shaped conical cones that also extend in the circumferential direction. It is formed by base surfaces 10, 20, and 30. Here, the ring-shaped conical truncated surfaces 10, 2
0 and 30 are inclined surfaces 10 having a taper whose diameter gradually decreases toward the tip 6b of the nipple portion 6.
a, 20a, 30a, and a ring-shaped truncated cone surface 10,
Flat portions 10b, 2 which are the rear end side portions of 20, 30
0b and 30b. As a result, the ring-shaped truncated cone surfaces 10, 20, and 30 have a shape similar to the outer peripheral surface of the truncated cone shape. The annular groove 8 has a rectangular cross section as shown in FIG. It is provided between the tip (minimum diameter portion) of the ring-shaped conical truncated surface 20 of the other first protrusion portion 17 adjacent to the first protrusion portion 17 .

The socket portion 12, which is another component of the hose joint of this example, has a cylindrical shape with an inner diameter larger than the outer diameter of the nipple portion 6, and is a member for caulking the nipple portion 6 to the hose. Therefore, the socket portion 12 is made of iron, aluminum, or the like so that it can be plastically deformed. FIG. 4 is a view showing the upper half of the socket portion 12 before it is attached to a hose, and as is clear from FIG. 4, the socket portion 12 of this example is separate from the nipple portion 6. The inner circumferential surface of the socket portion 12 is provided with three second protrusions 13. This second protrusion 13 is a ring-shaped conical truncated surface 1 of the first protrusion 7, 17, 27 of the nipple part 6.
Flat surface 10 which is the rear end side portion of 0, 20, 30
b, 20b, and 30b, and is continuously formed in a ring shape along the inner circumferential surface of the socket portion 12. Note that 12a is a mounting hole formed in the bottom wall 12b of the socket portion 12, and is mounted to the mounting portion 6e of the nipple portion 6.

Now, the connection of the hose joint of the first embodiment to the rubber hose 14 in which a reinforcing layer is embedded will be described. First, with the end portion 14a of the hose 14 inserted into the space between the nipple portion 6 and the socket portion 12, use a caulking tool or the like to tighten the socket portion 1.
2 in the centripetal direction of the socket portion 12, that is, the arrow 15
Press in the direction. Then, the socket portion 12 is plastically deformed by this pressing, and the socket portion 12 is caulked and fastened. In this case, as shown in FIG. 2, both ends of the socket portion 12 in the axial direction are generally caulked. When crimped,
The end 14a of the hose 14 is held between the first protrusions 7, 17, 27 of the nipple part 6 and the second protrusion 13 of the socket part 12, and the end 14a of the hose 14 is held on the inner peripheral surface side of the end 14a of the hose 14. The portion flows due to its elasticity and is pushed into the annular groove 8 of the nipple portion 6.

FIG. 5 shows a second embodiment of the invention. The second embodiment is basically the same as the first embodiment described above. However, the position of the annular groove 8 is different from that of the first embodiment. That is, the annular groove 8 of the second embodiment is formed between the vertical surface 19 of the first protruding part 17 provided in the middle of the first protruding parts 7, 17, and 27, and the first protruding part 17. It is provided between the tip of the ring-shaped truncated cone surface 10 of the first protrusion portion 7 on the rear end side. The hose joint in the second embodiment is also fastened to the hose in the same manner as in the first embodiment.

As shown in the first and second embodiments described above, in order to confirm the sealing effect of the hose joint attached to the hose 14, the relationship between the tightening rate and the leakage pressure was investigated. The test method was the same as in the conventional example shown in FIGS. 7a to 9a. That is,
According to JASOM319, after keeping the hose at 120℃ for 72 hours to deteriorate it to some extent, the socket part 1
A hole with a diameter of 2 mm is formed at a position 1.5 mm from the inner surface 12c of the bottom wall 12b of No. 2 near the second protrusion 13, with a depth reaching the reinforcing layer of the hose 14. After the hose 14 was sufficiently filled with driving oil at room temperature, it was pressurized using a nozzle tester. At this time, the nipple part 6 and the hose 1
When a pressure is applied that exceeds the sealing force with the inner surface of 4, fluid leaks through the 2 mm diameter hole.
In this way, the gauge pressure of the nozzle meter when fluid leakage occurred was defined as the leakage pressure. The pressure increase rate was 1750±700 Kg/cm ² per minute.

The test results show that the hose joint of the first embodiment has a power rating of approximately 330 to 400 kgf, as shown by the white circle in Figure 6.
cm ² , which is about 1.5~ compared to conventional hose fittings.
It can be seen that the number has increased dramatically by four times. In addition, the hose joint shown in the second embodiment has a high leakage pressure of about 280 to 390 kgf/cm ² , although it is slightly lower than that of the hose joint of the first embodiment, as indicated by the △ mark in Fig. 6. was gotten.

The reason why the sealing effect is dramatically improved in the hose joint of the first embodiment and the hose joint of the second embodiment is presumed to be as follows. That is, when fastening, the second protrusion 13 of the socket portion 12
moves in the centripetal direction, that is, in the direction of arrow 15,
The part on the inner peripheral surface side of the rubber hose 14 is the second protrusion 1
3 and the flat surfaces 10b, 20b, and 30b. As a result, the inner surface of the rubber hose 14 flows due to elasticity, and the ring-shaped conical surface 10
Slide in the direction of arrow A. Further, the inner peripheral surface side portion of the rubber hose 14 that has slipped in the direction of arrow A along the ring-shaped conical surface 10 is connected to the ring-shaped conical surface 20.
The flat surface 20b along with the rubber part located above
, and again along the ring-shaped truncated cone surface 20 as shown by the arrow A.
direction, and is pushed into the annular groove 8 from the lowest part of the ring-shaped truncated cone surface 20.

If the annular groove 8 is not provided, it is expected that the rubber will further flow in the direction of arrow B (see FIG. 4), that is, toward the other end of the rubber hose 14, and escape, as in the conventional case shown in FIG. 9a. be done. This circular groove 8
In the above-mentioned example in which the ring-shaped truncated cone surface 20 is provided, the rubber sliding in the direction of arrow A along the ring-shaped truncated cone surface 20 is pushed into the annular groove 8 as it is along the inclination of the ring-shaped truncated cone surface 20. Furthermore, in the above example, the second protrusion 13 and the ring-shaped conical frustum surface 30 of the first protrusion 27
Since the rubber is strongly compressed by the flat surface 30b that is the rear end side portion, the rubber once pushed into the annular groove 8 cannot escape in the direction of arrow B.
Therefore, in the example described above, the amount of rubber pushed into the annular groove 8 is extremely large, and the rubber filling rate in the annular groove 8 can be dramatically increased, thereby dramatically increasing the sealing effect. In this sense, in some cases, the protruding height of the second protruding part 13 facing the first protruding part 27 may be made slightly higher than other second protruding parts 13, or The protruding height of the protruding portion 27 can also be made slightly higher than the other first protruding portions 7 and 17.

On the other hand, the conventional hose joint shown in FIG.
In the conventional hose joint shown in Fig. a, the annular groove 101 and the annular groove 151 are
Although the required leakage pressure can be secured because the rubber is pushed inside, unlike the first and second embodiments, the rubber easily escapes, and therefore the annular groove 101,
It is presumed that the rubber filling rate in the annular groove 151 does not improve much and the sealing effect is small. Also, in the conventional hose joint shown in Fig. 9a, Fig. 9b
Since the rubber escapes in the direction of the arrow shown in , it is assumed that the rubber filling rate does not improve much and the sealing effect is small.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram conceptually showing the main parts of the nipple portion of the present invention. 2 to 4 show a first embodiment of the hose joint of the present invention, and FIG. 2 is a sectional view showing the hose joint fixed to the hose. FIG. 3 is an enlarged cross-sectional view of the main part of FIG. 2. FIG. 4 is a sectional view showing the upper half of the socket section. FIG. 5 shows a hose joint according to a second embodiment of the present invention, and is a sectional view corresponding to FIG. 2. FIG. 6 is a graph showing the relationship between leakage pressure and tightening rate in the embodiment and the conventional example. Figures 7 to 9 show conventional hose joints, and Figure 7a,
8a and 9a are sectional views of the main parts of the hose joint, and FIGS. 7b, 8b, and 9b are sectional views showing the flow of rubber. In the figure, 6 is the nipple part, 7, 17, and 27 are the first part.
Projections 9, 19, 29 are vertical surfaces, 10, 20,
30 is a truncated conical surface, 8 is an annular groove, 12 is a socket portion, and 13 is a second protrusion portion.

Claims (1)

[Scope of Claims] 1. A nipple portion having a central through-hole and inserted into the central hole of the hose, and a socket portion having an opening at one end that covers the nipple portion concentrically with the nipple portion and into which the hose is inserted. In the hose joint, the outer circumferential surface of the nipple portion includes at least two ring-shaped vertical surfaces arranged in series in the axial direction and substantially perpendicular to the central axis and extending in the circumferential direction, and an outer periphery of the vertical surface. a ring-shaped first protrusion portion formed of a ring-shaped truncated cone surface similar to a trapezoidal outer peripheral surface whose diameter decreases from the end toward the tip of the nipple portion; and 1. 1 extending in the circumferential direction provided between the vertical surface and the tip of the ring-shaped conical truncated surface of the other 1 first protrusion on the rear end side of the 1 first protrusion. annular grooves, and the inner circumferential surface of the socket part has at least a ring-shaped groove facing the rear end side of each of the ring-shaped truncated conical surfaces of each of the first protrusions of the nipple part. The first end of the hose is inserted between the nipple part and the socket part, and by pressing the socket part toward the center and caulking, each of the second protrusions is inserted. The hose is held between the first protrusion portion and each of the second protrusion portions, and the inner circumferential surface side portion of the hose is fluidly deformed toward the smaller diameter side of the ring-shaped conical truncated surface to form the ring-shaped A hose joint characterized in that the sealing effect is improved by pushing it into the annular groove of the nipple part from the small diameter side of the conical surface. 2. The annular groove is formed between the vertical surface of the first protrusion provided at the most distal side of the nipple part and the ring-shaped cone of the other first protrusion adjacent to the rear end side of the first protrusion. The hose joint according to claim 1, which is provided between the base surface and the small diameter end side. 3 The annular groove is the first groove located in the middle of the nipple part.
Claim 1, which is provided between the vertical surface of the protrusion and the small diameter end side of the ring-shaped truncated conical surface of the other first protrusion on the rear end side of the first protrusion. The hose joint described in item 1. 3 The annular groove is the first groove located in the middle of the nipple part.
Claim 1, which is provided between the vertical surface of the protrusion and the distal end side of the ring-shaped truncated conical surface of the other first protrusion on the rear end side of the first protrusion. Hose fittings listed in section. 4. The hose joint according to claim 1, wherein the ring-shaped conical surface is inclined at an angle of 15 to 40 degrees with respect to the central axis of the nipple portion. 5. The hose joint according to claim 1, wherein the rear end side portion of the ring-shaped conical truncated surface of the first protrusion portion is a flat surface substantially parallel to the central axis of the nipple portion.